Collection of Master’s Theses November 2012
Collection of Master’s theses
Civil Engineering and Geosciences Stevinweg 1 PO Box 5048 2600 GA Delft The Netherlands T +31(0) 15 27 85440 F +31(0) 15 27 87966
Faculty of Civil Engineering and Geosciences
November 2012
Master’s Theses November 2012
Civil Engineering and Geosciences Stevinweg 1 PO Box 5048 NL 2600 GA Delft The Netherlands Telephone: E-mail:
+31 (0)15 2784023
[email protected]
2 | Master’s Theses November 2012
Table of Contents Preface What is the graduation book exactly?
7 9
Building Engineering A search for structural applications of transparent plastics in the building industry Student: M. de Graaff The future of BIM and the construction industry Student: R. Legierse
12 13
Structural Engineering Design and modelling of cooling water intake risers for deep ocean applications Student: R. van Vliet Shear Capacity of Reinforced Concrete Slabs under Line and Wheel Load Close to the Support Student: P.H.A. van Hemert The transition between one-way shear and punching shear Student: J. Doorgeest Experimental determination of bearing capacity of transversely prestressed concrete deck slabs Student: M.W.J. Vugts Three-dimensional numerical analysis of tunnelling induced settlements. Student: J.M.J. Kappen Characterisation, non-destructive detection and strength of compression failures in tropical hardwood Student: H.P. Kuisch Soil-structure interaction modelling in performance-based seismic jetty design Student: F. Besseling Feasibility study for a standard viaduct Student: A. Gangaram-Panday Feasibility study on fiber reinforced polymer cylindrical truss bridges for heavy traffic Student: M. Chlosta Optimal Design of a module structure with sheeting Student: J. Xu Use of high strength steel grades for economical bridge design Student: E. Gogou Human error in structural engineering Student: J. de Haan Pile Penetration Simulation with Material Point Method Student: L.J. Lim Variant studie Spoorbrug in vvUHSB. Student: K. ten Pas Dimensioneren van bouwkuipen in 3D berekeningsmodellen Student: S.V. Bhagirath Finite element modelling of near field underwater noise generated by offshore pile driving Student: G. Kaushik Probability analysis of Life Cycle Cost of bridges with different preventive measures and repair methods Student: Y. Pan FEM modeling of fiber reinforced composites Student: E. Jongejans Cracking at the unheated side of a tunnel during the heating and cooling phase of a fire Student: S. van Aken
3 | Master’s Theses November 2012
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34
Wind Induced Vibrations of frUHSC Bridge decks Student: E. Bosman
35
Hydraulic Engineering Feasibility Study of an artificial sandy beach at Batumi, Georgia 38 Student: C. Pepping Influence of dredging on Columbia River Mouth morphology 39 Student: J. Stark Static and dynamic loads on the first row of interlocking, single layer armour units 40 Student: M.A. van de Koppel Modelling the anisotropy of turbulence with the SWASH model 41 Student: T. Bogaard Stability of open filter structures 42 Student: S.A.H. van de Sande Water level analysis based on North Sea storms 43 Student: M.S. de Jong Gate Design For Large, High Head Locks 44 Student: J. Doeksen Innovative guidance structure 45 Student: P. Spruijt Robust design in structural engineering 46 Student: C. Bus Coal transport Kalimantan 47 Student: B.C.Joppe Parametrisch ontwerpmodel 48 Student: P. van den Noort The future of the Oosterschelde with a new inlet channel 49 Student: R.A. de Bruijn Development of a generic automated instrument for the calibration of morphodynamic Delft3D model applications 50 Student: R.W. Hasselaar Stevin Outlet Sluices, wave impact under a beam 51 Student: G.M. Hofste Numerical modelling of Colorado sandbar growth 52 Student: B.J. Nieuwboer Golfrandvoorwaarden in havens 53 Student: S.P. Reijmerink Sedimentation-velocity in jet induced flow 54 Student: W.J. Siteur Determining vessel motions in a harbour due to waves 55 Student: P. van der Ven Relative Density of a Sand Fill 56 Student: W.C.N. Vessies Reliability of Quay Walls 57 Student: H.J.Wolters Innovative design for lock gates 58 Student: S. Zel Taat Upflow limestone contactor for soft and desalinated water 59 Student: P.B. Do “Traffic induced vibration in floating thoroughfares” 60 Student: E.J. Kaspers
4 | Master’s Theses November 2012
Sustainability as a Procurement Criterion for Port Investments Student: E.F.M. Broesterhuizen The influence of the wave height distribution on the stability of single layer concrete armour units Student: S.A.A. Zwanenburg Simulating Barrier Island Evolution Student: J.P. den Bieman RAMSSHEEP analysis: a tool for risk-driven maintenance Student: W. Wagner The morphological impact of the deepening of the deep foreshore on the Dutch coast Student: T. van Walsem
61 62 63 64 65
Hydraulic Engineering – COMEM Domain Calculation of Wave Forces using REEF3D Student: A.M. Kamath One-Dimensional Viscoelastic Simulation of Ice Behaviour in Relation to Dynamic Ice Action Student: M. Yazarov
68 69
Geo-Engineering Floating Piles Student: J.G. Bol
72
Watermanagement Pluvial flood damage modelling. Student: L. Sterna On the Topographic Classification of the Chemoga Watershed, Ethiopia Student: F.B.M. Desta Cold CANON: Anammox at low temperature Student: C. Fei Judgment under Uncertainty Student: S. Malek Pour Innovative Design of Gully Pot for Preventing Big particles Clogging Problem Student: Q. Hao Evaluation of hazard classification systems Student: W. Novalia Financial Sustainability of Rural Water Supplies in Western Kenya Student: A. Adams Water quality in bathing waters Student: I. Blommers Future Threats in drinking water winning from the Afgedamde Maas Student: A.H. Knol Transition experiments in Amsterdam; Student: N.I. Lugt Bonding and Bridging in Capacity Development Networks Student: M.M. Pieron Influence of wave climate schematisation on the simulated morphological development of the Western Scheldt entrance Student: B.W.F. van Rijn Evaluate two different PAC operations in combination with submerged ceramic MF membrane in surface water treatment Student: C. Yun
5 | Master’s Theses November 2012
74 75 76 77 78 79 80 81 82 83 84
85
86
Phosphorus removal by ceramic tight ultra-filtration (CTUF) membrane for RO pre-treatment Student: Z. Zeng Farmers’ Strategies Coping with Water Shortage; Student: B. Zhang Struvite Crystallization and Separation in Digested Sludge Student: W.J. de Buck
87 88 89
Transport & Planning Measuring the influence of congested bottlenecks on the route choice behavior of pedestrians at Utrecht Centraal Student: H.A.W. Voskamp A Framework for the Modelling and Ex-ante Evaluation of Coordinated Network Management Student: X. Zhang An Assessment Framework for the Speed Policy on Dutch Motorways Student: J. Kuijvenhoven Development of a prediction model for speed limit violations on tangent roadsections. Student: M. Zamanov Realised capacity estimation with use of vertical queuing method Student: M.J. Veenstra Quality assessment of an urban traffic network Student: T. Blanken The Effect of Network Structure and Signal Settings on the Macroscopic Fundamental Diagram Student: D. de Jong
Construction Management Engineering
92 93 94 95
96 97 98
99
Combining Early Contractor Involvement and Availability-Based Contracting in Complex Infrastructure Projects 100 Student: A. Beekers Assessing the Benefits of Construction Site Data Management 101 Student: M.S. Moran Applying the Supply-driven integrated design approach 102 Student: M.A. Moreno Sanchez
Last year’s Civil Engineering Theses
103
Master’s Theses June 2012
104
Master’s Theses March 2012
106
Master’s Theses October 2011
108
Master’s Theses June 2011
110
Master’s Theses February 2011
112
Research groups and professors within the faculty of Civil Engineering and Geosciences 6 | Master’s Theses November 2012
114
Preface
Every four months we publish a collection of abstracts of the theses produced by our recent Master’s graduates. In this collection you will find the theses of students who graduated in November 2012. We train our students to be more than just communicators of theoretical knowledge. We also teach them to be critical, make thorough problem analyses and take account of social contexts. We are convinced that a combination of theoretical knowledge and practical skills is needed to find effective solutions for social problems. The graduation project and associated thesis form the culmination of our students’ degree programme. In their graduation projects they examine a concrete problem and are required to employ all the knowledge they have gained during the previous years. By successfully completing this last step they have proven that they deserve to carry the title of Master of Science and that they are ready for the challenges of professional practice. In an age when the role and qualities of engineers are subject to more and more critical scrutiny, our graduates are still being welcomed with open arms by the labour market. They disperse to find jobs in various industries and most of them are offered work almost straight after their graduation. I see this as proof that a demand exists for the knowledge and skills of our graduates. So it is with pride that I present you with this collection of thesis abstracts. They demonstrate the high level that our graduates have attained and the breadth of the subject matter they have mastered. I would like to thank all those colleagues who contributed to this work with such energy and commitment. I wish our graduates every success with their careers and I trust that they will be just as enterprising in their future roles as they were during their studies. I hope that they continue to learn and create and keep testing the boundaries of the civil engineering industry. Professor B.M. Geerken Dean of the Faculty of Civil Engineering and Geosciences
7 | Master’s Theses November 2012
8 | Master’s Theses November 2012
What is the graduation book exactly? “Master’s Theses November” contains summaries of the theses produced by various students who obtained a Master of Science degree at the Delft University of Technology. The students in question graduated in “Civil Engineering”. The purpose of this publication is to inform professionals working in these fields about recent developments in teaching and research at the Faculty of Civil Engineering and Geosciences. In many cases, the subject of the Master’s thesis is based on a request from professionals working in the field in question. In other cases, such individuals will collaborate in the realisation of a Master’s thesis. Alternatively, the thesis may be part of a wider research project within the department itself. The primary goal of the Master’s thesis is to round-off a student’s course of study at the TU, and to enable them to graduate as a Master of Science. As the regulations stand, this requires an investment of 22 to 26 weeks of study. The summary of every completed thesis is published in “Master’s Theses June 2012”, whether they are merely average or truly outstanding.
The book’s layout The summaries of the various theses are published per Master’s programme and specialisation: The Civil Engineering Master’s programme has seven specialisations: • • Structural Engineering • • Building Engineering • • Hydraulic Engineering • • COMEM Domain • • Geo-Engineering • • Water Management • • Transport & Planning • • Construction Management and Engineering All of the summaries have a similar layout. Email the department in question if you require further details about a specific thesis (the email address is given at the end of each summary).
A Master’s programme spans several different departments, each of which corresponds to a specialisation within the programme in question. At the end of this book is a comprehensive list of specialisations, which includes the names of their respective professors.
The aim of the book The main purpose of publishing these Master’s theses is to ensure that the outside world is better informed about the research that is carried out at the Faculty of Civil Engineering and Geosciences. It is also hoped that this book will enhance communication with professionals working in this field, and help them to become better informed about the capacities of current graduates.
Further details Contact the department in question if you require further details about one or more of the published summaries (the phone number is given at the end of each summary). A small charge is sometimes levied to cover the costs of printing and posting a thesis. It is not always possible for us to send complete theses by post. It is possible to download the complete theses. The theses can be downloaded from: www.citg.tudelft.nl/GraduationSummaries Department of Education & Student Affairs 015-27 81199 / 81765 Department of Marketing & Communication 015-27 84023
Further information: Delft University of Technology Faculty of CEG, Department of Communications PO Box 5048 2600 GA Delft The Netherlands
The section containing the new summaries is followed by a comprehensive list of those produced last year. The layout of these summaries reflects that of the previous publications.
9 | Master’s Theses November 2012
10 | Master’s Theses November 2012
1. Civil Engineering theses
Building Engineering
1
Building Engineering
A search for structural applications of transparent plastics in the building industry
Transparent building appeals to imagination. The availability of glass in all shapes and sizes is continuously increasing; architects and engineers thankfully make use of the given opportunities. But glass has also some specific disadvantages, as it’s extreme brittleness. Luckily more materials are available that offer the desired transparency; transparent plastics might be a promising addition to the world of transparent building. Lack of information, their unusual characteristics and scepticism about their suitability make that transparent plastics are not yet an obvious choice for structural building applications. The transparent plastics that are considered most suitable for structural applications are Acrylic (PMMA) and polycarbonate (PC). They possess very good mechanical properties as strength and stiffness, compared to other plastics. Thereby the creep and weathering resistance of both materials is relatively high. In this research the behaviour of these transparent plastics is analysed and it is investigated whether and how the materials can be used in building structures, to further explore the dream of completely transparent buildings. Transparent plastics show some, for building materials, unusual characteristics, as thermoplastic and viscoelastic behaviour, special production techniques and a very low ratio between Young’s modulus and strength. This requires a different design approach. A case study is performed to get more feeling for the design with thermoplastics. To be able to use the freedom of shape and to explore the limits of the materials an observation tower is designed. An entirely transparent tower, made completely from transparent plastics. The design demonstrates that it is technically possible to design building structures in acrylic and polycarbonate.
Student: Thesis Committee:
Transparent plastics offer some promising possibilities for building design but still a lot will have to be investigated further before transparent plastic load bearing structures can be realised. For instance the improvement of detailing, the investigation of fire safety, buckling behaviour and the behaviour for a design life exceeding 20 years, which is now the limit by a lack of data. This will be a trajectory of years, but other materials have come that long road before. Once the plastics industry recognises the opportunities of investing in this new product market the development of suitable building products, standard details and optimised material compositions will certainly progress faster. Transparent plastics will probably never become a threatening substitute for standard glazing applications, the behaviour and suitable applications are incomparable. But transparent plastics have the ability to become a worthy colleague to glass in the future and to further extend the possibilities of transparent building.
M. de Graaff Prof.ir. R. Nijsse, Dr.ir. F.A. Veer, Ir. H.R. Schipper, Ir. R.M.J. Doomen
For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email:
[email protected]
12 | Master’s Theses November 2012
1
Building Engineering
The future of BIM and the construction industry
Giving insight into the future potential of BIM and to determine the next steps for developing BIM for the future construction industry
Background Many different parties are using BIM and apply it in all kinds of ways. For each project the potential applications of BIM are being determined. But there is not enough insight into which applications are useful in the future, how to apply these in projects and what steps need to be taken to develop BIM for the upcoming years.
Results Eventually a new system is introduced in which BIM takes on a certain role and contains the information of the construction process. With a development plan an interpretation is given to the use and implementation of the future perspective and the development of BIM into the new system. This development plan is divided into three phases with a number of steps. With an example a concrete interpretation is given.
The aim of this research is to provide insight into how to apply BIM now and in the future of the Construction Industry with a vision, and to describe the steps that need to be taken in a development plan which should lead to better support of the construction processes and a reduction of the costs of failure.
Research To explain what BIM is exactly first a definition is given for BIM, BIMming and Virtual Construction. With the use of a case study on the project A4 Delft – Schiedam and a literature study the current applications of BIM and the use of these applications have been determined. Hereafter a perspective is described for the future Construction Industry with the use of interviews with practitioners and key stakeholders from the Construction Industry. This perspective gives vision and direction for the development of the construction industry and the use of BIM for a longer period of time. It gives an answer to the question what to develop and why. The current problems of the construction industry and the current use of BIM are taken into account together with the major themes and the current developments.
Student: Thesis Committee:
R. Legierse Prof.dr.ir. H.A.J. de Ridder, Dr.ir. C.A. van Nederveen, Ir. R. Schipper, Ir. V.H.A. de Waal
For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email:
[email protected]
13 | Master’s Theses November 2012
2. Civil Engineering theses
Structural Engineering
2
Structural Engineering
Design and modelling of cooling water intake risers for deep ocean applications
Shell is currently developing the first Floating Liquefied Natural Gas (FLNG) facility in the world. It will be located 200 kilometres off Australia’s north-west coast at the Prelude gas field with a water depth of approximately 250 m. It will be used to receive, process, liquefy and store natural gas and load it onto LNG carriers, so that the liquefied gas can be transported directly to the market instead of going via the mainland. Eight water intake risers (WIR’s) of 150 m length are bundled together and deliver around 50,000 m 3/h of cold seawater to help cool the gas. A certain mutual distance between the risers is assured by so-called ‘spacers’. A sketch of the WIR bundle is seen in the Figure. For the development of other Shell gas fields, with larger water depths, there is potential to use similar facilities. Extension of the cooling water intake risers to 300 m at the deeper locations can increase the LNG production significantly, since water from larger depths is colder.
In practice there is little experience with application of long free-hanging water intake risers. It is not yet proven that the WIR design for the Prelude FLNG facility can be increased in length without major design modifications and applied at deeper fields. Analysis of interacting risers in a bundle is not straightforward. The objective of this MSc thesis is therefore to develop feasible concepts for the water intake risers that can be applied at deepwater FLNG facilities, select the best concept and build a numerical model to predict the behaviour of interacting risers that are closely spaced together in a bundle. Conceptual designs of 300 m long WIRs were developed considering different materials: a steel riser, a steel riser with a hinge somewhere along its length, a rubber riser and a riser with a steel upper part and a rubber lower part. These risers can be free hanging on the side of the vessel or applied in one or more bundles. From these concepts, a bundle of eight steel water intake risers with an outer diameter of 42” surrounding a structural riser is selected as the best concept for 300 m long water intake risers. A new numerical model is successfully built to predict the behaviour of interacting risers that are closely spaced together in a bundle. With this model it is determined that a minimum of four spacers is required along a riser bundle of 300 m length to assure a proper distance between the risers and make sure that the risers move with the same shape rather than individually. Also the optimum distribution of the spacers along the risers is found.
“Sketch of the steel WIR bundle for Prelude FLNG. Spacers keep the risers in the bundle at a certain distance from each other (Kuiper & Efthymiou, 2011)”
Student: Thesis Committee:
R. van Vliet Prof.dr. A.V. Metrikine, Ir. H. Hendrikse, Ir. N.F.B. Diepeveen, Dr. M.M. Efthymiou, Dr.ir. G.L. Kuiper,I r. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
16 | Master’s Theses November 2012
2
Structural Engineering
Shear Capacity of Reinforced Concrete Slabs under Line and Wheel Load Close to the Support
For more than a century, the shear capacity of beams, deep beams and slabs has been under theoretical and experimental research. Through these investigations, no accurate shear failure mechanism is developed for this phenomenon. One of the explanations for this result is that the behaviour of these members depends on more than twenty parameters. Delft University of Technology extends this research by investigation the behaviour of concrete slabs under a load combination. The hypothesis is that superposition of loads is possible on reinforced concrete slabs. To investigate the hypothesis, experiments are done with a line load and a concentrated load close to the support. Based on the previous series of experiments, with only a concentrated load close to the support, it is found that the hypothesis of superposition is true. The experimental results show a large margin of capacity as compared to the values calculated according to the national and international codes. Although the national and international standards are based on lower-bound theories, they are conservative. The shear capacity of reinforced concrete slabs depends also on the effective width, which is not included in most of the standards. As a last step in this research, the experimental results are analysed with the use of TNO diana. The reinforced concrete slabs are modelled as a three-dimensional problem with non-linear finite elements. In this case the finite element models are analysed with the modified Newton-Raphson method. Typically, non-linear finite element models, which are analysed with the NewtonRaphson method, have convergence problems. In this research the same convergence problem was discovered, but also the load-displacement curve has no accurate approximation in comparison with the experiment.
Student: Thesis Committee:
To investigate the convergence and behaviour of the reinforced concrete slab, the most important parameters are varied. Although the spring stiffness and the shear retention factor had a larger influence on the behaviour, the convergence problem disappeared when tension stiffening instead of tension softening was used. Usually, the finite element models give an accurate approximation in relation to the experiments. In this case there is no clear failure mechanism visible, so the shear behaviour of reinforced concrete slabs remains under investigation.
P.H.A. van Hemert Prof.dr.ir. J.C. Walraven, Dr.ir. C. van der Veen, Dr.ir. M.A.N. Hendriks, Ir. E.O.L. Lantsoght, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
17 | Master’s Theses November 2012
2
Structural Engineering
The transition between one-way shear and punching shear
Introduction In the past century many research has been done on the problem of shear failure. Recently the behavior of one-way spanning concrete slabs subjected to a concentrated load close to the support was investigated at Delft University of Technology. Experimental data has been analyzed to monitor the transition from one-way shear to punching shear.
Problem definition During the experiments the following questions arose: Will in such a situation one-way shear failure or punching shear failure occur and is it possible to predict this? Do the various building codes (NEN6720, Eurocode 2, ACI 318, Model Code 2010) provide safe results for these situations?
Research As the distance from the concentrated load to the support increases, the failure mechanism of the slab will change from one-way shear to punching shear. In the thesis it is investigated how the width of the slab and the shear span influence the failure mechanism. The investigation is done by using experimental data from tests and analyzing the failure mechanisms. A fine element model has been made to model two tests. One test failed in one-way shear and the other test failed in punching shear. After the two boundary situations were successfully simulated with the model, it was possible to investigate the transition between the two failure mechanisms. By varying the shear span and the element width the investigation was done. Various important building codes on shear are also applied to the tested slabs.
Results The investigation resulted in a graph consisting of three different areas representing three separate cases of shear failure, each with their own range of element width and shear span. Applying the various building codes on the tested slabs also resulted in some important findings.
Student: Thesis Committee:
Conclusions and recommendations Investigating the experiments, building codes and finite element models resulted in some interesting conclusions: • • It is possible to predict the occurring shear failure mechanism by using the finite element model or by using the graph. • • To provide a more thorough classification model, more parameters that influence the failure load and failure mechanism have to be investigated. • • The shear retention factor, used in the finite element model, was fitted by using the experimental data. It is recommended to find an average value for the shear retention factor that can be used in more general cases. In this way it would also be possible to predict the failure load more accurate. • • If the principle of effective width is to be applied in the building codes the value needs to be limited. As the shear span increases, the effective width and therefore the shear capacity increases. Experimental data contradicts this behavior.
J. Doorgeest Prof.dr.ir. J.C. Walraven, Dr.ir. M.A.N. Hendriks, Dr.ir. C. van der Veen, Ir. E.O.L. Lantsoght, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
18 | Master’s Theses November 2012
2
Structural Engineering
Experimental determination of bearing capacity of transversely prestressed concrete deck slabs
In the Netherlands traffic has grown rapidly over the years. The codes which were used to design the structures did not take into account the high values of today’s traffic. Therefore Rijkswaterstaat started doing research on all structures built before 1975. One of the investigated structures is the Van Brienenoord bridge. The bridge deck consists of prestressed girders with a transversely prestressed concrete slab between them. During the review of the old structures it was found that according to the current codes the Van Brienenoord bridge does not meet the requirements for structural safety. Although the bridge is loaded beyond its calculated capacity, it still is in a good condition. Explanation for this is the occurring phenomenon of compressive membrane action. Some countries have incorporated compressive membrane action into their codes for the design of structures by an empirical method. However, these codes do not take into account the presence of transverse prestressing in the slabs. The issue with the Van Brienenoord bridge is the relative slenderness of the concrete slab, the span to depth ratio is high. The foreign design codes set a limit on the slenderness of a slab in order to make use of the code. Because this requirement is not met, the codes assume that the occurring amount of compressive membrane action is too little to take into account as beneficial for the bearing capacity. However, the bearing capacity is increased by the presence of transverse prestressing. So the exact bearing capacity of the slender transversely prestressed slab remains unknown. This project includes a design of scale model which represents the properties of the Van Brienenoord bridge, where the effect of the transverse prestressing on the amount of compressive membrane action can be investigated. Also the bearing capacity of the slabs is predicted via analytical methods and finite element analysis.
Student: Thesis Committee:
Two analytical methods are used to calculate the bearing capacity of the slabs. Although these methods have not been validated with a lot of tests, the results are promising. Especially in comparison with Eurocode 2, the methods give results which are 7 to 9 times higher. During the finite element analysis it is demonstrated that the transverse prestressing level influences the bearing capacity of the slabs. The occurrence of a compression arch is clearly visible when the strains are examined. Also the behaviour of the slabs changes when the level is adapted. The first moment of cracking delays when the prestressing level increases. A very important parameter of the experiment is the skewness of the interface. When the forces of the skew interface are decomposed, an extra vertical force loads the slabs. The extra loading results in a lower capacity of the interface. The investigation of this parameter via finite element analysis demonstrates that the capacity of the skew interface is considerably lower than the capacity of a straight interface. When the failure loads during the experiment reach the values of the prediction in this thesis, the Van Brienenoord bridge will meet the requirements of structural safety. This is demonstrated by scaling back to the dimensions of the bridge. Add to this the increased concrete quality due to ongoing hydration and then the capacity increases even more. That would mean that strengthening the bridge is not necessary yet.
M.W.J. Vugts Prof.dr.ir. J.C. Walraven, Dr.ir. C. van der Veen, Ir. S. Amir, Dr.ir. M.A.N. Hendriks, Dr.ir. A. de Boer, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
19 | Master’s Theses November 2012
2
Structural Engineering
Three-dimensional numerical analysis of tunnelling induced settlements. The influence of masonry building geometry and location Recent tunnelling projects have received a great amount of media attention due to settlement induced damage. Due to the simplified approach of existing risk assessment methods, a new assessment system is under development, which can account for threedimensional structural aspects of buildings. The aim of this study is to investigate the influence of the position and geometry of masonry buildings on the development of damage, while undergoing tunnelling induced settlements. In line with previous research, three-dimensional finite element analyses are used as a tool to perform a parametric study. The results of this research are twofold. There are the results of a numerical robustness study and the parametric study itself, which express building characteristics in a certain vulnerability to tunnelling induced settlements. The results of the first section indicate that at least 20 load steps are required to obtain a numerically stable model with the default force convergence norm. Similar results can be obtained with a norm 1000 times stricter combined with 10 load steps. The parametric study consists of an evaluation of the parameters position, aspect-ratio, grouping and orientation. The position parameter is divided into three characteristics: the sagging zone, a combined settlement profile and the hogging zone. The aspect-ratio parameter is also divided into three characteristics: shallow buildings, square buildings and deep buildings. The grouping effect parameter also distinguishes three characteristics: small and large isolated buildings and grouped buildings. The orientation parameter includes seven different increasing angles of the building main axis with respect to the tunnelling axis. The maximum measured crack width in the buildings gives input for a classification of damage,
Student: Thesis Committee:
according to the system of Burland et al. (1977). An average trend in the damage classification indicates the sensitivity to tunnelling induced settlements of the parameters. Both during and after tunnelling, a position of the building in the combined settlement profile is the most sensitive to differential settlements. Buildings far away from the tunnelling axis generally obtain no more than slight damage. Structures with a low aspect-ratio seem on average to obtain equal amounts of damage as buildings with an aspect-ratio of 1. Structures with a higher aspect-ratio are less affected, both during and after tunnelling. Grouping of the buildings seems to be an influential parameter. Small isolated buildings obtain far less damage than large or grouped buildings. In relation to the numerical analyses, the empirical Limiting Tensile Strain Method (LTSM) seems to overestimate the damage for an isolated small building, but underestimate the damage in large or grouped buildings. For buildings in the sagging zone, a building with a low angle is the least sensitive to differential settlement, while the maximum measured crack width increases by increasing the angle. The difference in maximum crack width can grow to a factor 3. A building in the combined settlement profile or in the hogging zone displays opposite behaviour. Cases with low orientation angles are the most susceptible to damage, while increasing the angle to 90 degrees lowers the maximum measured crack width. The difference in results can grow up to a factor 2-3.
J.M.J. Kappen Prof.dr.ir. J.G. Rots, Dr.ir. M.A.N. Hendriks, Ir. G. Giardina, Ir. S. Pasterkamp, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
20 | Master’s Theses November 2012
2
Structural Engineering
Characterisation, non-destructive detection and strength of compression failures in tropical hardwood Timber intended for structural applications must be free of compression failures (CFs). CFs are defects in the wood structure, which can affect more than half of the stem’s cross section. It is important to detect CFs when timber is strength graded and assigned to a strength class. Certain national standards for timber grading do not allow the presence of CFs because CFs reduce the timber strength. Timber with CFs often shows brittle failure when loaded in bending and fails without any prior warnings. On rough sawn surfaces of tropical hardwood timber, CFs sometimes are very difficult if not impossible to detect with the naked eye. Non-destructive detection methods capable of detecting CFs do not exist yet on industrial level. A reliable detection method and methodology, for both less visible and non-visible CFs, is needed in order to fulfil the requirements of visual strength grading rules and to establish a relationship between the presence and characteristics of CFs and the corresponding bending strength of timber. Therefore, the main question of this master thesis was: “How can the bending strength be predicted of sawn tropical hardwood containing visually detectable CFs?”
Student: Thesis Committee:
In order to answer this question, first CFs were characterised and non-destructive detection methods were investigated on four hardwood species. Secondly, 4-point bending tests were carried out on samples with and without CFs to determine the reducing effect of CFs on bending strength (MoR). The MoR of samples containing CFs can be predicted using several nondestructive manners: 1. By pre-selecting timber which has a very low dynamic modulus of elasticity (Edyn). 2. By visual inspection on planed surfaces using CFs which are carefully inspected and measured. These CFs sizes were used in a multiple linear regression model. With this model a reliable indication of MoR for samples with and without CFs can be obtained. 3. By scanning timber using computed tomography based on X-rays (3D CT-scanning) or by using ultrasound transmission (C-scanning).
H.P. Kuisch Prof.dr.ir. J.W.G. van de Kuilen, Drs. W.F. Gard, Ir. G.J.P. Ravenshorst, Ing.W. Verwaal, Ir. E.P.J. Beckers, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
21 | Master’s Theses November 2012
2
Structural Engineering
Soil-structure interaction modelling in performance-based seismic jetty design
The importance of soil structure interaction in seismic design of structures is recognized by the modern seismic design community that is very much moving towards performance based design principles. Particularly for structures with deep foundations in soft soil conditions, soil-structure interaction is recognized to be an important factor that has to be considered in design. Jetty structures obviously are such structures. On the contrary, seismic design standards do hardly provide any straight forward tools for engineers to account for soil-structure interaction in design. It is clear that a problem exists, which has initiated this study. In the first phase of the study a literature review is conducted, where important developments relating to performance based seismic jetty design and soil-structure interaction are collected. Based on this literature review three suitable design approaches are found for jetty structure design, being simplified dynamic analysis (pushover + response spectrum), uncoupled dynamic analysis and coupled dynamic analysis. Then the second phase of the study is geared towards static pile-soil interaction and pushover analysis of single piles and jetty structures by modelling the soil as a conventional Winkler foundation or by performing more advanced hardening soil finite element analysis. Proper selection of clay parameters for the hardening soil model hereby is a critical step in order to be able to verify p-y expressions. After calibration of Winkler foundations for single piles, related issues like pile group effects are studied by means of finite element pushover analysis and subsequently p-multipliers for these effects can be defined for dynamic jetty analysis.
Student: Thesis Committee:
Subsequently the focus is shifted towards free field dynamic analysis of soil deposit for vertically propagating shear waves, because of its importance for seismic analysis of deep foundations. Both linear and nonlinear finite element modelling are performed and compared to equivalent linear frequency domain analysis solutions for layered soils. The conclusions drawn from this phase are important input for the jetty dynamic analysis. Then the seismic jetty response was calculated along the different methods. First by means of simplified dynamic analysis and then by both uncoupled and coupled dynamic analysis. Based on the results recommendations are proposed regarding the importance of soil-structure interaction for future jetty projects and how it should be accounted for, where both methods performance as well practical issues are taken into consideration.
F. Besseling Prof.ir. A.C.W.M. Vrouwenvelder, Prof.dr. A.V. Metrikine, Dr.ir. R.B.J. Brinkgreve, Ir. H.J. Lengkeek, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
22 | Master’s Theses November 2012
2
Structural Engineering
Feasibility study for a standard viaduct
Introduction
Research and result
In the past clients decided the design of viaducts. Nowadays the contractors get a lot more responsibility. They must design and execute the viaducts and, depending on the contract, also finance and maintain the viaduct for a certain period in the service stage. Both the client and contractor want to finalize a project quickly. The design of traffic viaducts with two spans is the main focus of the thesis. The research was done at BAM Infraconsult in Gouda, The Netherlands.
Problem definition All viaducts have the same goal: cross another road by a bridge type structure. Still the viaducts have another shape and are buildup of different elements. If the viaducts have the same function, the question is whether it is possible to use a standard viaduct and with this optimize the design phase of these structures. With this as the main goal the search for this optimization was started.
In the Netherlands two types of viaducts are used: viaducts with prefabricated beams in the deck and viaducts with a cast in situ deck. With a multicriteria analysis it is concluded that prefabrication is the best method to build the deck. Within the collection of prefabricated beams the study showed that the solid deck beam can be used till spans of 16 m and after that the box girders until 60 m. With the box girders the deck can be erected fast. The Nosing joint is the best expansion which can be used and lasts for 40 years. In the abutment it is always possible to use 2 pile rows for the foundation. In this way it is possible to make a good estimation of the deck length. In the future the possibility will be checked to get benefits from this standard abutment. Prefabrication or a special formwork can be some options. For the design phase a flow chart is made to make the right choice for viaducts with two spans by using the different standardized elements. With the flow chart it is possible to quickly make choices for the deck, expansion joints and the foundations. The piers and the edge of the deck have not been standardized. In this way every viaduct can have another (esthetic) look, while the basis is uniform.
Conclusions and recommendations It is possible to limit the time of the design phase by using a standard viaduct. By summarizing the design phase in a flow chart, it is possible to make the first choices quickly and after that make some design calculations. It is recommended to use the flow chart for practical projects to determine if it is an effective tool. If needed, the flow chart should be optimized.
Student: Thesis Committee:
A. Gangaram-Panday Prof.ir. A.Q.C. van der Horst, Dr.ir. C. van der Veen, Dr. M.H. Kolstein, Ing. C. J. vander Zwaard, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
23 | Master’s Theses November 2012
2
Structural Engineering
Feasibility study on fiber reinforced polymer cylindrical truss bridges for heavy traffic
Considering the recent increase in the use of fiber reinforced polymers in the civil engineering industry in general and in the bridge engineering industry in particular, as well as the recently more and more applied cylindrical truss bridge type, this research focuses on the question whether it is possible to combine fiber reinforced polymers as stand-alone structural material and this bridge type to construct a bridge suitable for heavy traffic as well as bicycle and pedestrian traffic. This research combines an extensive literature study on the use of fiber reinforced polymers for bridge engineering with a theoretical feasibility- and design-study on fiber reinforced polymer cylindrical truss bridges for heavy traffic. During the design study the spatial needs of all bridge users were defined to obtain an initial shape of the bridge. This shape was then optimized in several steps using finite-element-modeling and -analysis, yielding a final shape of the bridge. The behavior of this structure under design loads was then extensively investigated, again using finite element analysis, showing that the bridge could very well meet the self-derived deflection limit for fiber reinforced polymers at relatively low stress levels. Since fiber reinforced materials are a very diverse field of material, with hundreds of different compositions being available, the first result of this study was the choice of a suitable composite for further analysis. For this bridge design very high fiber content (>60%) carbon/epoxy composite was used. The main reason for this choice was the high modulus and -strength of the carbon fibers and the high durability and strength of the epoxy resin. A major reason of the slow implementation of fiber reinforced polymers in the bridge engineering industry are the worries concerning the lack of fire safety of the material. The literature study of this research showed however that it is possible to construct a heavy traffic full-FRP truss bridge, while complying with the known fire safety standards. The virgin FRP material can be adapted by several fire-protection measures; it turned out that a combination of intumescent gel-coating and low volume phosphorous filler systems works best in increasing the fire
Student: Thesis Committee:
resistance and thereby providing a fire resistance class of R30 for hydrocarbon fire curve loading. The initial shape of the bridge was optimized in three stages: first several different truss topologies, which were derived with a parametric geometric model, were analyzed and compared using finite element analysis software, yielding the square truss with one diagonal as most efficient topology. In the next steps several grid sizes of this truss as well as several cross section dimensions were compared, again using finite element analysis software. An optimum was found between minimum material usage and minimum deflection, which reduced the material usage of the main load bearing elliptical truss by about 40% compared to the initial variant. The optimized structure was then fitted with the inner bridge deck supporting trusses as well as the cantilever trusses. The elliptical truss bridge performed very well considering the maximum deflections and stresses under Eurocode design loads and load combinations that were derived in finite element modeling software. When comparing the full-FRP bridge design with similar, existing steel structures, the maximum deformations and –stresses were considerably lower for the full-FRP bridge while only weighing about 60% of the steel structure. This research showed that the ‘new’ cylindrical truss bridge type is not only an aesthetically appealing structure but also performs structurally very well when combined with fiber reinforced polymer as structural material. It turned out that fiber reinforced polymers can be used as stand-alone structural material for medium span heavy traffic bridges. Next to that, this research clarified that there is no legitimate structural reason for the fact that fiber reinforced polymers are used relatively scarcely in the civil engineering- and bridge engineering industry compared to traditional building materials such as steel and concrete. Since this research is one of the first researches of its kind, using FRP as stand-alone structural material for a relatively new and complex bridge type, more research is needed in the field of high order connections for fiber reinforced polymer circular hollow sections. Next to that the possibility of the use of differently sized and shaped cross sections for the truss members should be investigated.
M. Chlosta Prof.ir. F.S.K. Bijlaard, Dr. M.H. Kolstein, A.De Boer, Dr.ir. M.A.N. Hendriks,
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
24 | Master’s Theses November 2012
2
Structural Engineering
Optimal Design of a module structure with sheeting
The master thesis work was carried out at Delft University of Technology with a contract with Chicago Bridge and Iron B.V. (CB&I). The project is focused on an optimal design of a steel structure with sheeting. A comparative analysis is made among different alternative sheeting types. The structural behavior of the sheeting is investigated first. Based on the total investment cost analysis, a recommendation for the optimal design is given. A literature review has been undertaken firstly regarding the current module structure design. Specific design criteria of the module used by CB&I are described. Possible sheeting configurations are proposed and investigated in detail. The stressed skin design concept is introduced in the frame structure design. A comparison is made between the conventional design and the stressed skin design concept. Furthermore, a total investment cost analysis is carried out which is the chosen criteria for the final structure type. A substation module was taken as a study case. A conventional beam and column module was built in STAAD PRO. The optimized plate model was built up using the stressed skin concept. The global models are optimized by dozens of attempts and the final configurations meet all the design criteria. By investigating the global model, the critical load case on the structure was found.
Then three plate topologies were investigated in the thesis work, individually stiffened flat panel, corrugated plate, and composite sandwich panel. They were modeled in STAAD PRO with adjacent frames. The critical load was applied on the local plate model to check the capacity. The local plates were adjusted a lot of times to obtain satisfactory results. Every plate topology is comparable with each other under the same structural performance. After determining the final configuration of the three plates, the total investment costs of the structure were esimated. The sandwich panel can reduce most weight (13%) and the corrugated plates can save most money (15%). The general information in the thesis provides guidance to the enclosed module design in practice using the stressed skin design. Detailed design aspects are simply mentioned and further in-depth research is needed for practical use.
Student: J. Xu Thesis Committee: Prof.ir. F.S.K. Bijlaard, Prof.ir. C.A. Willemse, Dr.ir. M.A.N. Hendriks, Ir. R. Abspoel, Ing. G. Langerak, Ir. L.J.M. Houben For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
25 | Master’s Theses November 2012
2
Structural Engineering
Use of high strength steel grades for economical bridge design
Introduction In Europe S355 is mainly the steel grade used for bridge design. Moreover, higher steel grades (e.g. S690) exhibiting improved material properties (e.g. higher strength, improved toughness, excellent forming and welding properties) are also available for more than three decades already but their use is quite limited. This study has been done in cooperation with Iv-Infra with the scope to investigate the use of higher steels grades (mainly S690) in steel bridges.
for design of connections and further optimization. Finally, hybrid (S690 and S355) and homogeneous (only S355) truss bridge design alternatives both with (RHS) and circular hollow sections (CHS) have been developed and compared on a (total) costs basis.
Problem definition In contrast to US and Japan, in Europe the market demand for high strength steels (HSS) is restricted mainly due to lack of design codes and long term experience, which results in an extremely high price for these steel grades in comparison to mild steels (e.g. in the Netherlands S460 and S690 are 40% and 75%, respectively, more expensive than S355). In addition, HSS offers significant cost benefits due to reduced cross sectional dimensions and steel weight mainly when strength is the governing design criterion. However, in case of bridges other factors may govern namely fatigue and/or stability. Therefore, it is customary to consider that in these cases HSS can offer no (cost) benefits for bridges.
Research The aim of this thesis project is to present potential advantages that high strength steels (HSS) have to offer in case of bridges but also possible disadvantages and ways of improvement. In order to achieve that the research has been divided in two main parts: 1. Initially a literature survey has been performed with respect to high strength steel material focused mainly on steel grades up to S700 in Q&T quality. Later on several preliminary bridge designs (i.e. global calculations for a box girder, a truss girder and an arch bridge with respect to strength, fatigue, stability and HSS S690) for a single span (L= 105 m) bridge in the Netherlands (Schellingwouderbrug) have been developed. 2. Based on results from part 1, a truss bridge design with rectangular hollow sections (RHS) was chosen
Student: Thesis Committee:
Final hybrid truss design alternatives for the ‘Schellingwouderbrug’
Results • • Hybrid designs show significant steel weight reduction (even 65% for hybrid truss bridge design with RHS members) in comparison to their equivalents “all in S355” designs. • • For the truss bridge with RHS the fatigue behavior of the joints has been proven insufficient. Thus alternative design with gusset plates has been proposed. • • The arch bridge design is governed by fatigue stresses mainly due to high bending moments in the main girders, thus application of HSS S690 would not lead in an economical design.
Conclusions/reccomendations The results from literature and trial bridge designs for a long span bridge clearly indicate that despite the currently high price of HSS the steel weight and construction costs can be reduced with the increase of steel strength. Fatigue and stability may influence the choice of the bridge type and design of connections. Fatigue behavior of HSS connections requires further research.
E. Gogou Prof.ir. F.S.K Bijlaard, Dr. M.H. Kolstein, Dr.ir. P.C.J. Hoogenboom, Ir. W.P.J. Langedijk, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
26 | Master’s Theses November 2012
2
Structural Engineering
Human error in structural engineering The design of a human reliability assessment method for structural engineering In the recent past a number of buildings collapsed in the Netherlands under apparent normal circumstances. The causes of these failures are predominantly human error within the design or construction of the building. Examples of this are the collapse of five balconies of an apartment building in Maastricht in 2003, and the partial collapse of a roof structure under construction of a football stadium in Enschede in 2012. Based on these developments it is of importance to investigate the current building practice concerning the occurrence of human error. The objective of this research is to investigate the effect of human error within the design process on the reliability of building structures. Based on this, the following research question is defined: What are the consequences of human error within the design process on the structural reliability of a typical building structure? The research question is answered by proposing a Human Reliability Assessment (HRA) method and subsequently analyse the effect of selected human actions within the design process. The HRA model is developed for specific use within engineering tasks and encompasses four basic steps: Qualitative Analysis, Human Error Quantification, Design Simulation and Probabilistic Analysis. The first step in the HRA model is to define the process of interest and its boundaries (Qualitative Analysis). The selected process is a structural design process of a beam element within a common office building. Within the analysis two beam types are considered: a statically determined beam element and a statically undetermined beam element. Furthermore two scenarios for specific analysis are selected: the level of professional knowledge and the level of design control. The second step within the HRA method is to quantify the probability of failure within an individual design task (Human Error Quantification). This probability of failure is represented by a probability distribution function expressed by two parameters: a Human Error Probability (HEP) and an Error Magnitude (EM). The procedure for determining HEPs consists of two methods: a basic HEP method and an extended HEP
Student: Thesis Committee:
method. The extended method is labour intensive and requires quite some knowledge concerning human factors. The simplified method requires considerate less efforts and knowledge, however this method is only applicable for standard design tasks. The third step is to combine the individual task probability distributions to obtain an overall probability distribution of the element strength due to errors in the process (Design Simulation). For this, a Monte Carlo simulation procedure is proposed. Within this simulation process, each design task is modelled with an algorithm which models the design task at hand and the occurrence of failure. Furthermore design control is modelled as well in order to investigate the proposed scenarios. The last step in the model is to determine the probability of failure of the engineered structure (Probabilistic Analysis). For this a probabilistic analysis method based on plastic limit state analysis is proposed. The overall probability distributions found in step three, combined with probabilistic loading conditions are used to determine the structural failure probability. From the case study it can be concluded that the statically determined beam element is slightly more susceptible to structural failure. Within both structural types (statically determined and undetermined beam elements), the influence of design experience on the structural failure is limited, while the effect of normal supervision is somewhat higher. It should be noted that these results are based on a simple case study, selecting a more complicated case study will probably lead to somewhat other results. Nevertheless, it can be concluded that the proposed HRA model has the potential to quantify the effect of human error within carefully defined boundary conditions. However further research is required to increase the accuracy of the model and its practical use.
J. de Haan Prof.ir. A.C.W.M. Vrouwenvelder, Dr.ir. P.C.J. Hoogenboom, Ir. K.C. Terwel, Ir. A. Rolvink, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
27 | Master’s Theses November 2012
2
Structural Engineering
Pile Penetration Simulation with Material Point Method
The pile penetration process involves extreme deformation of soil around the penetration region, causing a mesh distortion problem if the conventional finite element method (FEM) is used. The material point method (MPM) meanwhile has been successfully used in analysing some engineering problems involving large deformation without the issue of mesh distortion. However, MPM generates numerical noise in the calculation of stresses when material points cross element boundaries due to the discontinuity of the gradient of the shape functions. To solve this noise issue, the Dual Domain Material Point (DDMP) is used. DDMP introduces a modified gradient of the shape function by combining the continuous gradient of the shape functions and the conventional ones. In this study, the application of DDMP is further extended within an implicit scheme by formulating the consistent tangent system. In addition, the weight function of DDMP is modified to improve its performance in the Newton procedure.
Because an MPM analysis is computationally more expensive than FEM, a mesh-relaxation technique has been proposed to couple the MPM and FEM analyses. Contact algorithms between the pile and the soil are carried out by using inherent no-slip contact in MPM and a level-set-based sliding contact algorithm. Finally, the implementation is used to simulate the pile penetration process in two dimensional and three dimensional models.
Pile penetration of a 3D Model
Student: Thesis Committee:
L.J. Lim Prof.dr.ir L.J. Sluys, Dr.ir. R.B.J. Brinkgreve, Dr. P.J. Vardon, Dr.ir. A. Andreykiv, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
28 | Master’s Theses November 2012
2
Structural Engineering
Variant studie Spoorbrug in vvUHSB.
In deze thesis wordt onderzocht in hoeverre de toepassing van vvUHSB voordelen heeft ten opzicht van de traditionele materialen en op welke wijze vvUHSB kan worden toegepast in combinatie met de huidige geldende NEN-EN normen. Deze thesis is opgedeeld in een tweetal delen, waarbij in het theoretische kader een opzet wordt gemaakt welke facetten belangrijk kunnen zijn voor het ontwerpen in vvUHSB. Hierin wordt met name de krachtswerking, loadmodellen, materiaal-eigenschappen en andere aandachtspunten toegelicht. Naast de optimalisaties die binnen de bestaande NEN-EN normen vallen, wordt er in de thesis een variant op partiële voorspanning toegelicht.
of andere versterkende effecten op de verplaatsing, als gevolg van herhaaldelijke belasting. Dit bevestigt de bepaling in de NEN-EN 1991-2 waarin de gevoeligheid voor dynamische effecten wordt gekoppeld aan de initiële verplaatsing als gevolg van het eigen gewicht. Beide toetsingen geven dus aan dat het risico van de dynamische effecten niet van toepassing is bij de ontwerpsnelheid van vmax=160 km/h. Bij herhaaldelijke belastingen op een constructie zal er direct moeten worden gedacht aan de effecten van vermoeiing. Hoewel dit tot op heden over het algemeen geen bepalende factor was, dient er bij het steeds slanker en lichter worden van de constructie steeds meer rekening te worden gehouden met de vermoeiing van het materiaal in de constructie. In deze thesis is het ontwerp dat voort is gekomen uit de optimalisaties, getoetst op de vermoeiingscapaciteit. Hierbij komt naar voren dat de benadering zoals opgesteld in de NEN-EN 1992-2 niet aansluit bij de toepassing van vvUHSB in de praktijk. Als gevolg van een conservatieve benadering van de vermoeiingsterkte zal de constructie niet voldoen aan de eisen. De lage vermoeiingssterkte is het gevolg van de beperkingen van de NEN-EN 1992-2. Deze is opgesteld voor de toepassing van betonmengsels met een lagere capaciteit, en andere eigenschappen. Echter door experimentele onderzoeken te koppelen aan de bestaande normen is het mogelijk om een bevredigend resultaat te behalen. Door middel van de Hannover-benadering is de vermoeiingssterkte van vvUHSB te bepalen, waardoor de vermoeiingstoets gunstiger uitkomt.
Hierbij wordt de eigen treksterkte van het materiaal verwerkt in de ontwerpberekeningen. Hierdoor is er te besparen op de benodigde hoeveelheid voorspanning. Daarnaast wordt de constructie dynamisch doorgerekend d.m.v. een numeriek benadering. Hierin worden de doorsnede eigenschappen van het geoptimaliseerde ontwerp, verwerkt in een model dat gekoppeld is aan de “real trains” zoals omschreven in de NEN-EN 1991-2. Deze numerieke toetsing resulteerde niet in resonantie
Student: Thesis Committee:
K. ten Pas Prof.dr.ir. J.C. Walraven, Dr.ir. C. van der Veen, Dr.ir. M.A.N. Hendriks, Ing. J. Blitterswijk.
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
29 | Master’s Theses November 2012
2
Structural Engineering
Dimensioneren van bouwkuipen in 3D berekeningsmodellen Stempeluitval als calamiteiten belasting In dit afstudeerproject is op basis van een parameterstudie in 3D-berekeningsmodellen nagegaan of het stempelraam krachten technisch voldoende weerstand kan bieden aan het voorval stempeluitval. De analyse van stempeluitval is uitgevoerd met als grondslag de praktijkrichtlijnen van CUR 166 m.b.t. de geotechnische analyse en staalnorm Eurocode 3 m.b.t. de constructieve analyse. Het stempelraam is in de parameterstudie geanalyseerd bij voorval stempeluitval door uit te gaan van een stempelraam dat primair is gedimensioneerd en geoptimaliseerd conform de 1e orde elasticiteitstheorie van staal in de UGT op basis van de belastingen die voortvloeien uit het plane strain model. Vervolgens is dit stempelraam getoetst aan de sterkteen stabiliteitseisen conform de 1e en 2e orde elastische berekening in de BGT op basis van de belastingen die voortvloeien bij stempeluitval uit het 3D-model. Uit de analyse van stempeluitval is geconcludeerd dat het stempelraam, met name de gording, niet beschikt over voldoende reserve om stempeluitval te kunnen weerstaan conform de 1e en 2e orde elastische berekening. De gording ter plaatse van het uitgevallen stempel ondervindt ondanks de reductie van de lokale horizontale korrelspanning een enorme verhoging in krachten en momenten.
Student: Thesis Committee:
In dit afstudeerproject is ook onderzocht of de plastische reserve in het stempelraam, indien daar sprake van kan zijn, het fenomeen stempeluitval kan weerstaan. Bij een plastische berekening van het stempelraam (1e orde plastische berekening) zijn de sterkte- en stabiliteitstoetsen van de gording weliswaar her en der iets gunstiger vanwege de eventuele plastische reserve, maar deze reserve is niet altijd voldoende om stempeluitval te kunnen weerstaan. Naast de stempeluitval analyse is de ontwerpfilosofie voor bouwkuipen en stempelramen volgens CUR 166 vergeleken met de in veelal internationale literatuur voorkomende Engelse ontwerprichtlijn CIRIA publicatie C580 en C517 met de focus op de berekeningsfilosofie bij stempeluitval. Hoewel de onzekerheden conform beide ontwerprichtlijnen volgens hetzelfde principe in rekening gebracht worden, verschilt de mate van pessimistisch zijn in de leidende parameters enigszins. De Engelse norm CIRIA gaat strenger om bij het bepalen van de karakteristieke waarden van de grondparameters bij stempeluitval dan CUR 166. In CUR 166 zijn verder geen eisen opgenomen voor de toelaatbare maaiveldzakkingen bij stempeluitval. De maximale maaiveldzakking bij stempeluitval in het bovenste stempelraam heeft een patroon dat overeenkomt met het “spandrel type”, waarbij de veldzakking maximaal is ter plaatse van de damwand. Deze zakking kan oplopen tot 1,5 à 3,0 maal de berekende maaiveldzakking bij de normale situatie.
S.V. Bhagirath Prof.ir. A.F. van Tol, Ing. H.J. Everts, Dr.ir K.J. Bakker, Dr.ir. R.B.J. Brinkgreve, Ir. J.F. Joosse, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
30 | Master’s Theses November 2012
2
Structural Engineering
Finite element modelling of near field underwater noise generated by offshore pile driving
The primary objective of this research is to study, by means of numerical simulation, the acoustic and dynamic characteristics of the pile driving process. In order to estimate the noise generated from the offshore pile driving process, a finite element model is developed by using the finite element software tool ADINA. In the preliminary stage of the model development, a three dimensional and an axisymmetric pile-fluid interaction model without the presence of soil elements is considered to understand the basic characteristics of wave propagation in the surrounding fluid as a result of pile driving. The potential based fluid elements available in ADINA Structures are used for the analysis. The results of the analysis are found to be in good agreement with the findings of past researchers. The results of the three-dimensional and axisymmetric analysis are comparable within the desired accuracy limits. Apart from that, the time taken by the analysis is considerably reduced in the case of axisymmetric modelling. Therefore, in the second phase of model development, an axisymmetric model is further developed and the soil properties are incorporated. For the simulation of soil two possibilities are explored: a) Spring-Dashpot model, b) Fluid model.
Student: Thesis Committee:
In the first case, soil is modeled with the spring and dashpot elements whereas in the latter case, soil is modeled with the general fluid elements. This analysis is performed with ADINA-FSI because spring-dashpot elements cannot be used with potential based elements. The developed model is analysed to study the influence of soil elements on the acoustics of the pile driving process. It is observed that the pressure development in the surrounding fluid elements is highly dependent on the dashpot and spring coefficient used in the analysis. In the final phase of the research, a parametric study of the developed model is performed. The effect of various parameters such as the inclination angle of the loading, the radius of the artificial nonreflective boundary, the radius of the pile and the seasoil interface is analysed. The results showed that the inclination angle of the loading has a considerable effect in the neighbourhood of the pile whereas its effect is negligible at a distance far away. A strong correlation is obtained between the pressure development and the radial distance. However, no such correlation can be established in case of depth. With the increase in the radius of the pile, an increase in the pressures is observed during the analysis. The whole study shows that the simulation model is an effective mean to study the influence of various factors on the pressure development in the surrounding fluid without the need to conduct large scale experiments.
G. Kaushik Prof.dr. A.V. Metrikine, Ir. J.S. Hoving, Ir. A. Tsouvalas, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
31 | Master’s Theses November 2012
2
Structural Engineering
Probability analysis of Life Cycle Cost of bridges with different preventive measures and repair methods Nowadays, a lot of reinforced concrete structures begin to show signs of deterioration. Repairing them by conventional repair not only costs a huge amount of money, but also leads to disruption of traffic and inconvenience. There is a strong incentive to find out the cheapest way to extend the service life of existing structures and to design and build new reinforced concrete (RC) structures which will require less maintenance and repair over their lifetime. Chloride-induced corrosion of reinforcing bars is the primary cause of deterioration of RC structures. Conventional repair (combined with hydrophobic treatment) and Cathodic Protection are most frequently used for repair of chloride-contaminated structures. Applying preventive measures is the way to build more durable new buildings. Three methods namely using stainless steel, applying hydrophobic treatment and Cathodic Prevention were considered in this project. Using different preventive measures and repair methods will involve different costs and will have different influences on the service life of structures. In order to find out the cheapest way to maintain a bridge, a life cycle cost (LCC) method was adopted. The life time of bridges with different preventive measures and repair methods was determined based on data from literature or calculated based on probabilistic methods. Among the three repair methods, Cathodic Protection (CP) is a relatively new technique and samples from structures having CP for around 20 years have been examined by SEM trying to reveal the degradation mechanism. The costs of the preventive measure and repair methods were derived from practical situations.
Student: Thesis Committee:
Following that, a life cycle cost tool was developed using an example, which is an ongoing Cathodic Prevention (CPre) project in Groningen. The influence of different preventive measures and repair methods on the total life cycle cost has been studied using the model. Results show that to apply preventive measures is generally cheaper than to repair the structures after they deteriorate. Using stainless steel and hydrophobic treatment as preventive measures are the cheapest way to maintain a bridge over 100 years. To repair with conventional repair combined with hydrophobic treatment is the repair method which leads to the lowest life cycle cost. CP and CPre have the advantage that the structural condition is being monitored. In a sensitivity analysis, initial cost and discount rate were found to be the factors which have the biggest influence on the life cycle cost. SEM studies are recommended to be carried out in a comprehensive way in order to determine the service life of CP. In terms of LCC modeling, it is recommended to determine the time intervals for reapplication of the four repair methods using probability methods. It is also recommended to take the probability of price change of the measures into account.
Y. Pan Prof.dr. R.B. Polder, Dr. O. Copuroglu, Dr.ir. S.A.A.M. Fennis, Dr.ir. W. Peelen, Dr.ir. W. Courage, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
32 | Master’s Theses November 2012
2
Structural Engineering
FEM modeling of fiber reinforced composites
Recently several studies have been performed at the TU Delft on the use of the generalized finite element method (GFEM) to model fiber reinforced composite materials in a two dimensional space. The GFEM model allows a large number of arbitrarily placed fibers to be taken into account. The fibers are placed on top of the ordinary mesh and therefore do not require aligned meshing to be done. Matrix material, fiber material and the interface between them each have their own material parameters. The discontinuous displacement field on the fiber, also known as the “fiber slip” is taken into account by the use of extra degrees of freedom. These extra degrees of freedom are placed on the original nodes of the elements crossed by fibers.
Both approaches produce very similar numerical results. The ERS approach is more efficient as the current GFEM approach.
Fibers are in essence one dimensional objects. The main degree of freedom they should have is the slip in the direction of the fiber. It is therefore computationally expensive to use extra degrees of freedom on top of regular element nodes to describe the displacement field of the fiber. Why not inserting the extra degrees of freedom in the direction of the fiber on top of the fiber itself? In this thesis a search is done to an efficient element with extra degrees of freedom on the fiber. A first unsuccessful try is the use of a so called “Interfaceenriched GFEM” element (IGFEM). The second successful approach is the slightly different “embedded reinforcement approach including bond slip” (ERS). This is an element that has been used before in calculating reinforced concrete in several publications. This element is used here for calculating elastic material reinforced with many fibers. In its mathematical derivations, a small extension is made to allow for an arbitrary enrichment function to be inserted on the fiber displacement field analogous to the GFEM derivations. This enrichment function inserts a priori knowledge into the solution allowing it to converge faster. However, enrichments in this research are kept simple. Next to a two dimensional implementation of the GFEM and ERS approach, a three dimensional implementation is presented. Encountered problems and numerical examples for both models are discussed.
Student: Thesis Committee:
E. Jongejans Prof.dr.ir. L.J. Sluys, Dr. A. Simone, Dr.ir. C. van der Veen, Ir. L.J.M. Houben
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
33 | Master’s Theses November 2012
2
Structural Engineering
Cracking at the unheated side of a tunnel during the heating and cooling phase of a fire
This thesis focuses on assessing the crack width and durability at the outside of an immersed tunnel in case of fire inside the tunnel. Previous research (for instance Nieman) addressed only the heating phase of a tunnel while also the inevitable cooling phase may have a large influence on the crack width. A user supplied code was written to calculate both the heating and cooling phase and handle the different reversibilities of the material properties. The material model is based on an explicit strain model where some simplifications had been made such as uniaxiality and the omission of the Poisson ratio. This material model is validated on some small models; the tunnel calculations are performed by making use of the geometry of the Wijkertunnel.
The results of the tunnel calculations showed good agreement with the results of TNO 2007 for the own weight and pressure loading. During the heating phase the results start to deviate from TNO 2007, partly due to differences in the material model (load induced thermal strains reduce the compressive stresses in the walls), partly due to instabilities in the calculation process. The load induced thermal strain decreases the thermal strain under compressive stresses and first time heating.
One analysis could follow the complete fire, heating and cooling phase. During the heating and cooling phase the convergence behaviour was poor which is partly due to the complex material behaviour. The material model should be improved to obtain a more stable calculation process. During the cooling phase the tensile stresses increased in the roof and decreased in the walls of the heated tunnel tube as expected. The crack width at the outside of the tunnel is cumulative over a specific area. A lower limit is calculated and a crack width of more than 1 mm is found. This could influence the durability of the tunnel. To support this indication more calculations should be performed. The effect of the load induced thermal strain shows a decrease of the tensile stresses in vertical direction in the walls and the compressive stresses in the side wall which are present for a longer time. In the mid wall an increase in compressive stress can be seen as a consequence of the net shrinkage which is a consequence of the load induced thermal strain during the cooling phase. It is possible to analyse the crack width during a fire. However more tests need to be performed to get a better understanding about the behaviour of the material properties during heating (high temperatures) and cooling. The code must be validated more thoroughly and only when the deformations of the walls can be explained for sure, a good assessment of the crack width after a heating and cooling phase can be made. In this thesis a foundation is laid for assessing the crack width in immersed tunnels during a heating and cooling phase. No such model existed until now. This model should be perfected, particular with respect to convergence, in order to obtain a more stable calculation and reliable results.
Student: S. van Aken Thesis Committee: Prof.dr.ir. J.G. Rots, Dr.ir. M.A.N. Hendriks, Prof.dr.ir. E. Schlangen, Ir. C. van der Vliet, Ir. A.J. Breunese, Ir. L.J.M. Houben For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
34 | Master’s Theses November 2012
2
Structural Engineering
Wind Induced Vibrations of frUHSC Bridge decks Buffeting Performance of a frUHSC Bridge Design
Owing to the development of fibre reinforced ultra high strength concrete (frUHSC), more slender structures can be developed. Problems that were never governing for concrete structures can now become more important for design. In the research the buffeting performance of a frUHSC bridge is investigated and compared with the performance of a normal strength concrete (NSC) bridge. A traditional cable stayed bridge is designed for the concrete classes C35/45 and C170/200. For this design the weight of the bridge deck can be reduced with 40% by applying frUHSC. But not only the bridge deck can be made more slender, material can also be saved in the stays and the substructure as well. The goal of the project is to investigate whether or not the frUHSC bridge is more susceptible for vertical vibrations due to wind buffeting in comparison with a NSC bridge design.
Deformed plot of the FE-model in Matlab For the analysis an analytical model and a FE-model are used. For the analytical model the main span of the bridge is modeled as an Euler-Bernoulli beam on an elastic foundation with at both ends a rotational spring. By means of a FE-model of the bridges a second analysis is performed. This FE-model is designed in Matlab with two dimensional two nodes Euler-Bernoulli beam elements.
Student: Thesis Committee:
Example of the displacements of the midspan of the bridge for a certain time-domain From the analysis it becomes clear that for both bridge designs the fundamental frequencies are about the same. For the fundamental frequency of the NSC bridge the deviation between the analytical model and the FE-model is 2.2%. For the frUHSC bridge design deviation between the models is 5.9%. So the first natural frequency of the FE-model corresponds very well with the first natural frequency of the analytical model. However, the deviation in the response of the displacements and especially the accelerations is very large. This is because the third and the fifth natural frequency of the analytical model have far lower values compared with the natural frequencies of the FE-model. Therefore have these natural frequencies more influence on the response of the system. But probably the most important observation is that both bridge designs have approximately the same fundamental frequency, but the response of the frUHSC bridge is for the vertical displacements and accelerations in all the different analysis more than 59% higher than the response of the NSC bridge.
E. Bosman Prof.dr.ir. J.C. Walraven, Dr.ir. C. van der Veen, Dr.ir. P.C.J. Hoogenboom, Prof.dr.ir. C. Geurts, Ing. P.A.M. Taken, Ing. M. Wiggers
For further information, please contact the section of Structural Engineering tel. 015-2784578 Email:
[email protected]
35 | Master’s Theses November 2012
2
Structural Engineering
36 | Master’s Theses November 2012
3. Civil Engineering theses
Hydraulic Engineering
3
Hydraulic Engineering
Feasibility Study of an artificial sandy beach at Batumi, Georgia
Introduction Batumi is a city located on the coast of the Black Sea in the southwest of Georgia. The coastline south of Batumi is affected by erosion problems. The coastal stretch between the port in the north and the Chorokhi River south of Batumi should be protected. In 2010 Alkyon/ARCADIS proposed a detailed design to protect this coastal stretch. The beaches of Batumi originally consist of pebble. In the northern part of the coastal stretch, the so called Old Boulevard, a lot of tourist activities take place. Along this part of the coast sandy beaches where requested by the client. In the design proposed in 2010, pocket beaches have been envisaged here. These pocket beaches consists of pebbles up to a level of MSL +3m and a layer of sand above MSL +3m. In this thesis an alternative design for the pocket beaches are proposed. This design should contain more sand and less visual structures, opposed to the pocket beaches proposed in the 2010 study. This master thesis aims to determine the best design option and the feasibility of an artificial sandy beach along the Old Boulevard of Batumi. In order to determine suitable measures and alternatives, the morphological impact of the measures and the corresponding sediment transports have been considered. The sediment transport rates have been computed using numerical models. For the longshore transports the model UNIBEST-LT is used and the crossshore losses are determined with the use of the XBeach model.
on their costs. From the MCA follows that a fully sandy beach placed parallel to the boulevard and a perched beach with a beach placed parallel to the boulevard are the most promising alternatives. The fully sandy beach has a better rating for the qualitative criteria where the perched beach is the cheapest solution. Because of the small differences between both alternatives in qualitative criteria, but a noticeable difference in the total costs, the perched beach is selected as the most promising alternative. A preliminary design has been prepared for this alternative. The perched beach consists of a sandy beach with a width of 135 meter. At Approximately 180 meter from the shoreline a submerged breakwater is present with a submergence of 0.5 meter.
Conclusion The pocket beaches as designed in the 2010 study and the preliminary design of the perched beach as designed in this study are finally compared. The pocket beaches have a partly sandy beach and contain some undesirable visual structures. The perched beach fulfils the wish of a fully sandy beach with almost no visual structures, the costs are however considerably higher than for the pocket beaches, 25.5 M€ versus 56.6 M€. It can be concluded that the two options have their own benefits and drawbacks. The preference depends on which aspect is valued as most important and/or which aspect is valued as least important.
Alternatives With the use of gained information of the behaviour of a sandy beach and possible measures to optimise the design of an artificial sandy beach, 7 alternatives are proposed. The 7 alternatives are compared and assessed with the use of a Multi-Criteria analysis (MCA). The alternatives are rated on 6 qualitative criteria and
Student: C. Pepping Thesis Committee: Prof.dr.ir. M.J.F. Stive, Dr.ir. M. Zijlema, Ir. J. van Overeem, Ir. M.C. Onderwater
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
38 | Master’s Theses November 2012
3
Hydraulic Engineering
Influence of dredging on Columbia River Mouth morphology
A numerical modeling study is performed about the impact of dredging and disposal activities on the long-term morphological development of the Columbia River Mouth (MCR). The MCR is flanked by two large jetties, which were constructed in the late 19 th century to improve navigation possibilities. Jetty construction initiated large-scale morphological changes. This morphological development was mainly driven by tidal flow, a seasonal varying discharge and high-energy wave climate. In addition, dredging activities displaced relatively large amounts of sand. Approximately 120 Mm 3 was dredged from the MCR between 1958 and 1999. Only one-third of this volume was disposed in the active littoral zone. The remaining amount was placed at offshore disposal sites and is probably lost for the littoral system. Therefore, dredging activities might be an important factor for the long-term morphological development and for recent erosion trends at the coasts directly adjacent to the MCR.
tional supply due to disposal activities. Meanwhile, the sediment supply function of the shoal for the adjacent coastal cell was maintained. Other effects of dredging and disposal activities were the formation of distinct sand mounds at the locations of some disposal sites and maintaining the southern orientation of the MCR channel at the estuary side of the inlet.
Methodology The net influence of both dredging and disposal activities is analyzed with a Delft3D model. Morphological acceleration techniques and wave climate reduction are used to bridge the gap between hydrodynamic and morphological time scales. The model performance and capabilities are assessed with simulations for the 1926-1958 interval. These simulations indicate that the model captures the large-scale morphological changes that occurred in the study area. Simulations for the 1958-1999 interval are then used for the analysis of the impact of dredging and disposal activities.
Main implication of the model results for disposal strategies is that the sand volume of the Peacock Spit shoal should be maintained to avoid further erosion of the shoal and prevent undermining of the North Jetty and to maintain the sediment supply function of the shoal for the updrift coastal cell.
Results Based on the model results, dredging activities led to significant volume losses in the inlet itself and in the area west of the river entrance. On the Peacock Spit shoal directly north of the inlet, the volume losses due to dredging are almost completely reversed by disposal of dredged material on the shoal itself. Dredging and disposal activities did not have significant effects for the littoral drift at coastal stretches adjacent to the MCR. In the studied interval, the Peacock Spit shoal did absorb the negative effects of dredging and the addi-
Student: J. Stark Thesis Committee: Prof.dr.ir. M.J.F. Stive, Ir. A.P. Luijendijk, Dr.ir. E. Elias, Dr.G. Gelfenbaum, Dr.ir. J.E.A. Storms, Ir. D.J.R. Walstra For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
39 | Master’s Theses November 2012
3
Hydraulic Engineering
Static and dynamic loads on the first row of interlocking, single layer armour units
Interlocking, single layer concrete armour units are placed in a specific grid depending on the type of armour unit. Within this grid, armour units are placed in horizontal rows. The number of horizontal rows of single layer armour units on a breakwater is limited to 20. This limit is proposed in order to prevent major settlements, which might affect the interlocking of the armour units. The limit on the number of rows is based on experience from prototypes and is not yet confirmed in a systematic study. Then number of rows also might have an effect on the load on the first (bottom) row of armour units, which affects the structural integrity of the armour units. The load on the first row of armour units is however unknown. The research presented in this thesis is a study on the load on the first (bottom) row of concrete armour units placed on a breakwater. Both the static load and the dynamic load were examined. The static load is defined as the load on the bottom row of armour units resulting from the higher positioned rows of armour units during conditions without waves. The dynamic load is defined as the load on the bottom row of armour units during conditions with wave attack minus the static load. These loads were studied by physical model tests. The static load was studied in an experiment in which the down slope force on the bottom rows of armour units (Xbloc units of 366 grams) was continuously measured during the placement of 20 rows of armour units on a slope of 37 degrees (slope of 3:4) in a series of 15 tests.
experiment resulted in a relationship of the measured static load on the first row of armour units with the number of rows applied on the slope of the model. From this relationship appeared that the static load approaches a maximum value after 10 rows. An analytical model was developed and validated against the measured results. This model gives an interpretation of the cause of the maximum value. The measurements of the dynamic load showed two clear phenomena. The dynamic load appeared to be a harmonic load with the same period as the waves imposed on the model. The dynamic load is the result of the flow of water along the armour layer. The maximum dynamic load on the first row of armour units occurred simultaneous with the maximum downwash which is in line with expectations. A relation between the downwash velocity and the amplitude of the dynamic load was found. The second observed phenomenon is the increase of the wave averaged load on the first row of armour units during the test. During the tests the harmonic load oscillated around an equilibrium line which showed a positive trend. The measured load after testing was significant higher than the measured load at the beginning of the tests. A relation was found between the wave characteristics and the increase of the load on the first row of armour units.
The dynamic load was studied in a physical model test in a wave flume. The first row of armour units was placed on a movable frame which was connected to a load cell. The dynamic load was measured during tests with regular waves of 20% to 100% of the maximum wave height corresponding to the used armour unit (Xbloc units of 61.7 gram which were positioned on a typical breakwater slope of 3:4) and a wave period corresponding to an Iribarren number of 3, 4 and 5 for all of the described wave heights. This static load
Student: Thesis Committee:
M.A. van de Koppel Prof.dr.ir. W.S.J. Uijttewaal, Ir. J. van den Bos, Ir. H.J. Verhagen, M. Muilwijk,
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
40 | Master’s Theses November 2012
3
Hydraulic Engineering
Modelling the anisotropy of turbulence with the SWASH model
Heterogeneous roughness conditions in open channel flows In this study the focus is on modelling turbulence anisotropy in open channel flows with the SWASH model. Turbulence anisotropy significantly influences the flow features of: channel flows with heterogeneous roughness conditions, curved open channel flows, compound channel flows with different floodplain depths, etc. The SWASH model is a non-hydrostatic wave-flow model, mainly used to predict the transformation of surface waves from offshore to the beach. For this study, adaptations were made to this SWASH model, in order to model turbulence anisotropy. Two different modelling approaches were used: RANS modelling and Large Eddy Simulation (LES). The SWASH model is extended with a non-linear k-ε closure to the RANS equations, since the standard linear closure does not take turbulence anisotropy into account. A 3D subgrid model is implemented to perform LES. The performance of the LES code and the RANS model with the non-linear k-ε closure is tested on two flow geometries: an open channel flow with homogeneous bottom roughness conditions and an open channel flow with parallel smooth to rough bed sections. Results of the RANS computations, for both horizontal homogeneous and non-homogeneous open channel flow, show good agreement with laboratory measurements of Muller and Studerus [13], Nezu and Rodi [17] and Wang and Cheng [32].
Student: Thesis Committee:
Although there is a number of closure constants involved with the non-linear k-ε model, additional tuning of these coefficients was not necessary for this study: both the homogeneous and non-homogenous test case were simulated successfully using the standard values proposed by Speziale [25]. With its low computational costs and robustness, the non-linear k-ε model appears to be a useful extension to the SWASH wave-flow model. LES results for horizontal uniform flow are validated with DNS data of Moser, Kim and Mansour [12]. Especially near the bed the LES results deviate from the DNS data. The mean velocity, as well as the transverse and vertical turbulence intensities, is seriously underestimated. The deviation from the DNS data is related to the use of non- periodic boundary conditions, the coarse grid resolution, the size of the computational domain and the amount of numerical dissipation that is involved. Since it is the bottom region where secondary currents are generated, the use of the present LES code for problems involving heterogeneous roughness is not appropriate.
T. Bogaard Prof.dr.ir. W.S.J. Uijttewaal, Dr. M.Zijlema, Dr.ir. B.C. van Prooijen
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
41 | Master’s Theses November 2012
3
Hydraulic Engineering
Stability of open filter structures
Granular filters are used for protection against scour and erosion. For a proper functioning it is necessary that interfaces between the filter structure, the subsoil and the water flowing above the filter structure are stable. Stability means that there is no transport of subsoil material through the filter to the water above the filter, and that no filter material is removed by currents above the filter. Three types of granular filters can be distinguished; 1. Geometrically closed filter structures, 2. Stable geometrically open filter structures, 3. Unstable geometrically open filter structures. This research is focusing on stable geometrically open filter structures. Recently, a desk study has been carried out by Deltares resulting in a new theoretical formula for single layered geometrically open filter structures (CUR, 2010). Hoffmans improved the theoretical formula that had been founded by Deltares (Hoffmans G. , 2012) The goal of this research was to verify the formula found by Hoffmans [2012] for structures loaded by currents (flow parallel to the filter construction). As part of the verification of the design formula ten flume experiments were performed in the Environmental Fluid Mechanic Laboratory at Delft University of Technology. After the execution of the model tests an extensive analysis was made based on the performed model tests and model tests performed in the past (Bakker [1960], Haverhoek [1968], Wouters [1982], Konter et al. [1990], Van Huijstee and Verheij [1991] and Van Velzen [2012]).
Student: Thesis Committee:
The analysis showed that the formula is valid for single layered geometrically open filter structures loaded by currents. Two adjustments to the design formula are proposed: 1. The relative layer thickness fits better when related to the nominal diameter of the filter material; 2. The alpha value proposed by Hoffmans [2012] is too high (new alpha values are 30% to 60% lower). The original formula as proposed by Hoffmans [2012] gives unrealistic values for situations with wide graded filter material. Model tests showed that the relative layer thickness is better represented when related to the nominal diameter of the filter material. The design formula can be used for design purposes. The design of a single layered geometrically open filter structure can be schematized in two steps; 1. Firstly, determination of the material that should be used for the top-layer; 2. Secondly, determination of the layer-thickness of the filter/top-layer taking into account filter and base material characteristics.
S.A.H. van de Sande Prof.dr.ir. W.S.J. Uijttewaal, Ir. H.J. Verheij, Ir H.J. Verhagen, Ir. J.P. van den Bos
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
42 | Master’s Theses November 2012
3
Hydraulic Engineering
Water level analysis based on North Sea storms
Protection of the land against the sea is an important issue for the Netherlands. Already since the era of the Romans the Netherlands have been fighting against the sea. Especially storm surges are a major threat for the Dutch coastal areas. Safety standards have been set to defend the coastline against these surges. For the coast of Holland the probability of occurrence was set to 1% per 100 years. Based on extrapolation of the historic dataset of water levels, this results in a water level height of NAP + 5m for 10 -4/year condition. To date no study has been done to analyse the effect on water level for the Dutch coast from the passage of storms over the North Sea. This research examines the feasibility of developing a joint probability method to determine the extreme water level for the Dutch coast, resulting from these storms. This has been done by means of a parametric model, which determines the hydraulic boundary conditions from a set of significant storm parameters. The objective of this research is to obtain physical knowledge in predicting the water level for the Dutch coast. This provides a better understanding of the contribution of storm characteristics to high water levels, and can therefore be very useful in the forecasting of extreme surges from the passage of these storms. Secondly, possible changes in meteorology can be taken into account in this model, in contrast to the current method. Another advantage is that the simulated wind field based on storm parameters may also be a tool for simulating and understanding the behaviour of waves for the North Sea and the joint probability with the water level.
Student: Thesis Committee:
Based on the developed parametric model for Hook of Holland, the 10 -4/year water level is approximately NAP + 5.45m. This compares well with the water level based on the current method. Furthermore, the results suggest that much higher water levels can occur, albeit with a very low probability. It should however be noted that there is still a considerable spread of the observed values around the simulated water level. This model also provides insight in the influence of individual storm characteristics on the extreme water level for Hook of Holland. The parameters with the most significant impact are: the central pressure, the latitudinal starting point, the forward movement of the storm, the radius to maximum winds and the Holland B parameter. As with any model the results depend critically on the volume and the quality of the available data. For this research the dataset of applicable storms was relatively small. A larger dataset will not only offer more data, but also provide more understanding of the interdependence of storm parameters. This will help to refine the model and hence obtain a more reliable estimation of the extreme water level. Additionally, this study offers a basis for expansion to obtain further understanding of the behaviour of water in the North Sea basin. Particularly, the wind field analysis is not only applicable for the water level estimation, but can also be used for analysing waves. It can also be worthwhile to investigate whether this method is also applicable for other regions and countries.
M.S. de Jong Prof.drs.ir. J.K. Vrijling, Dr.ir. P.H.A.J.M. van Gelder, Dr.ir L.H. Holthuijsen, Dr.ir. M. van Ledden, Ir. C. den Heijer
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
43 | Master’s Theses November 2012
3
Hydraulic Engineering
Gate Design For Large, High Head Locks The development of an innovative lock gate
Introduction The increasing dimensions of ships and the development of new navigation infrastructure result in increasing dimensions of locks. Therefore lock gate dimensions are also increasing and conventional technologies are being scaled up, to the new dimensions and demands emplaced by the infrastructure system. However, it is questionable if up-scaling conventional technologies will provide optimal solutions and the objective of this study is therefore: To research the need and possibilities of innovative lock gate design for future large, high head locks. Finally developing an innovative gate design, that is geared towards diminishing the drawbacks of extrapolated technologies. Meeting the future requirements emplaced by the navigation infrastructure system.
Current Lock Gate Technologies and the Future A historical data analysis has been performed, contemplating over 220 of the worlds largest locks throughout time, analyzing the development and application of conventional lock gate technologies. From this, the conclusions have been drawn that the required lock gate dimensions of a number of future projects, fall far outside the application area of current technologies (see figure a), and that it may not be assumed that conventional technologies will lead to optimal solutions at this scale. In addition, a number of aspects will be highlighted for future large & high head lock gate design, especially reliability, water consumption and its effects on the locks accessibility.
The application of current technologies and the field of innovation
Student: Thesis Committee:
Some illustrations of the Sliding Arch Gate
The Sliding (tension) Arch Gate A new lock gate technology has been developed specifically attuned to the future dimensions and highlighted requirements resulting into the design of: ‘The Sliding Arch Gate’ (see figure b), an extremely slender gate design, using (tension) arch action to transfer loads to the lock head structure, minimizing recess dimensions and water consumption. In addition, the absence of submerged moving / mechanical parts, minimizes maintenance requirements and the modular design of the gate enhances ease of maintenance, transport and manufacture. The Sliding Arch Gate has been worked out to an operational design level, using the Panama Canal Expansion Project as reference, in order to evaluate its potential performance and to make comparison with conventional technologies. From the evaluation it has been concluded that Sliding Arch Gate will require higher initial investments but that major benefits are achieved by reduced water consumption and low maintenance. The first of which can result into over $2,000 mln. in added revenues for the Panama Canal, during the commercial lifetime of the gate, due to increased lockage capacity. It has thus been concluded that new/ innovative technologies, like the Sliding Arch Gate, can outperform up-scaled conventional technologies. However as the design of the Sliding Arch Gate is still in a pioneering stage, there are many optimizations to be found and uncertainties to be investigated.
J. Doeksen Prof.dr.ir. J.K. Vrijling,Ir. W.F. Molenaar, Dr.ir. R.A.J. van Ostayen, Ir. H. van Stralen, Ir. P.T. van der Sar
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
44 | Master’s Theses November 2012
3
Hydraulic Engineering
Innovative guidance structure Technical and economical feasibility cable variant
Guidance structures are built in the vicinity of a sluice complex to serve as berth for ships waiting for the sluice to be available. The structure is loaded by the ship and should stop the ship without being damaged. The design of a guidance structure did not significantly change over the last decades. Therefore one could talk about a traditional structure. The structure consists of vertical supports with horizontal beams covered with timber. A new solution is found by mr. Ros who proposes to use pre-tensioned cables to stop the ship. The high tension capacity will make it possible to significantly reduce the use of material. The load on a guidance structure is formed by the ships kinetic energy. The interaction between ship, water, structure and soil will determine the reaction force by which the ship is slowed down. The influence of the water is formed by added water mass and damping through wave radiation. A cable structure has relatively low stiffness which leads to a larger stopping length, which implies more kinetic energy to absorb through the water influence. The guidance structures should be able to serve the entire fleet. The stiffness needs to be low enough for an empty ship which hits all the cables and high enough for a loaded ship which only hits the lower cables. To guaranty safety, the ship should not be able to sail underneath any cable. The solution is found in the use of an integral pre-tensioning system. By a balancing bar the cables are connected and able to interact. A lever beam with counter weight is used for pre-tensioning. With this system the vulnerability for stretch, creep, relaxation, deformation or temperature is minimal. Skirts are providing vertical stiffness, so all cables will deform together.
Student: Thesis Committee:
Cables are connected to vertical supports. Those supports are relatively stiff compared to the stiffness halfway the span. Calculations showed the stiffness of the guidance structures increases gradually as the ship approaches the support. To get the ship safely past the support a support glider is invented. The support gliders are also used to prevent crushing of the cable between support and ship. The determent factor for the design of a cable guidance structure is the cable span. For a first design the situation at Krammersluizen (Netherlands) is used. The span is 57,6 meter and the total length is 288 meter. With the use of a maximum allowable stopping length, the needed pretension force is calculated. Only elastic deformation of the supports is allowed. This limits the maximum stopping length to 1,0 meter in the case of 57,6 meter cable span. Optimizing the design is done through varying the amount of support and thereby changing the cable span. Even the extreme case of 1 span of 288 meter has a solution that satisfies all demands. The steel cables have a design factor of 2,3. Reducing the amount of supports leads to a net profit. Extra costs for cables and the pre-tensioning system are not as big as the savings by reduction of the amount of steel. The cheapest possibility is a cable guidance structure with 1 support. Due to placement of bollards and ladders a minimum of 4 supports are needed. The cost reduction for this design is 32% and the reduction on environmental impact 44%. The cable guidance structure is technical and economic feasible. Further research should focus on the proposed issues to reduce costs and environmental impact even further.
P. Spruijt Prof.dr.ir. J.K. Vrijling, Ir. W. van den Bos, Dr. A. Romeijn, Ir. A. van der Toorn, J. den Ouden, D. Ros, E. van Dijk
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
45 | Master’s Theses November 2012
3
Hydraulic Engineering
Robust design in structural engineering
Robustness has recently become a popular term in structural and hydraulic engineering. Examples are the robust ‘superlevees’ that have been constructed in Japan or the robust surcharge on the dike heights as proposed in ‘Leidraad Rivieren’. Also, many methods for designing a robust design have been proposed in scientific literature. However, the concept of ‘robust design’ has no clear definition. The aim of this thesis was to find a definition for a robust system and to use this definition to search for a practical application of robust design in structural engineering.
Literature study: Definition The literature on robust design has been extensively studied to establish a definition for a robust system. It was concluded that a robust system is least sensitive to changes in the uncertain parameters, such as loading and strength. The reason to choose for a robust system is that the costs during the lifetime will be reduced. If this were the only goal, it would be justified to design a system that is reliable, even under extreme values of the uncertain parameters. However, in practice, investment costs should be taken into account, as well as the probability that such an extreme value occurs.
Robust design in practice It was concluded that the lifecycle costs of a robust system are least sensitive for model discrepancies. The choice for a robust system does however depend on the relative importance of the investment costs and the risks. Robustness will often reduce the risk, but increase the investment costs. Several case studies were done to investigate this tradeoff between robustness and investment costs. From the case studies it was concluded that robustness can be achieved by increasing the reliability of the system, or by searching for a robust design alternative. Increasing the reliability will always increase the investment costs. A way to design a robust system without automatically increasing the investment costs, is to search for a robust design alternative. An example is given in the figure, in which it is shown that a dike with a stone revetment is more robust than a dike with a clay- and grass cover, under discrepancies in the distribution parameters of the water level and the wave height. Bus1.png
Literature study: ‘Robust’ design methods Several so-called ‘robust’ design methods were tested for their applicability in structural engineering. Some of these methods did not consider investment costs, while others were based uncertainty that was described by convex models instead of probability distributions. It was concluded that these methods are all inferior to the lifecycle cost optimization as introduced by van Dantzig, when it comes to the practice of structural engineering. In this method, the aim is to find a design for which the sum of the investment costs and all risks over the lifetime, is minimal. This means that the investment costs and all lifecycle costs, as well as their probability of becoming reality, are taken into account equally.
Student: Thesis Committee:
C. Bus Prof.drs.ir. J.K. Vrijling, Prof.ir. A.C.W.M. Vrouwenvelder, Dr.ir. P.H.A.J.M. van Gelder, Ir. A. Willems, Ir. W.D. van der Wiel
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
46 | Master’s Theses November 2012
3
Hydraulic Engineering
Coal transport Kalimantan
This master thesis focuses on the transportation of coal from two coalmines in South Kalimantan to the Java sea. Coal has to be transported from the coal mine area, situated hundred kilometre land inward, to a location with sufficient water depth, at the mouth of the river Barito. The objective of this master thesis is summarized in two research questions. What are the possibilities to transport coal from the mine hundred kilometre land inward to a location with sufficient water depth to load Cape-size coal carriers? Which of the alternatives are most feasible from a technical and financial point of view?
The current transport system consists of several cycles of barges, where full barges sail one way and empty barges sail the other way back. Two different cycles have been investigated. A cycle with barge transport between two terminals and a cycle with barge transport between a terminal and an anchorage for loading coal carriers Hydraulic transportation of coal is an unconventional transport mode. Hydraulic transportation of coal is very similar with the transportation of sand in the dredging industry. The coarse coal is first mixed with water and then transported through a pipeline by means of a number of centrifugal pumps in series. The main differences between a coal-water slurry and a sand-water slurry are the density of the particles and the average particle size (dm 50) Sands consists mainly of quarts with a density of 2650 kg/m 3, while coal has a density between 1100 kg/ m 3 and 1500 kg/m 3, depending on the quality and the origin of the coal. The particles are transported in water, therefor the relative density underwater determines the tendency of settling. The relative density is 1650 kg/m 3 for sand, respectively 300 kg/m 3 for coal particles. This means that the tendency of settling is around 5 times higher for sand than for coal.
The biggest challenge for the new transport system is to increase the throughput capacity five times in five years. Three different transport modes have been investigated in this thesis. Those are; transport by barges, conveyor belt transport and hydraulic transport. A comprehensive logistics study is performed with the use of a simulation model. The simulation model is written in Matlab and is a so-called event based model. The transport configuration which is lowest in transport costs, is determined with the results from the simulation model. A transport configuration is a combination of the number of barges, number of berths and the loading capacity of the berths.
Student: Thesis Committee:
The particle size of coal, when it is exported, is much larger than the average particle size of sand (between 63µm 2000µm). Larger particle sizes will increase the turbulent behaviour of the slurry. Different formulas for a coal-water slurry are analysed. In the analysis is investigated which influence the particle density and particle size have on the friction head in a particular formula.
B.C. Joppe Prof.ir. T.Vellinga, Ir. P.Quist, Dr.ir. W.Daamen, Ing. M.G.M.Huijsmans
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
47 | Master’s Theses November 2012
3
Hydraulic Engineering
Parametrisch ontwerpmodel Toepassing op een onderdoorgang
Inleiding Het spoor- en wegennetwerk kruist elkaar in Nederland op veel plaatsen met behulp van spoorwegovergangen. Dit is geen ideale situatie in verband met de veiligheid en doorstroming. Daarom worden veel kruisingen vervangen door onderdoorgangen. Het ontwerp van een dergelijke onderdoorgang begint in de regel iedere keer opnieuw, met weinig hergebruik van kennis. Vanuit verschillende partijen is de vraag ontstaan of dit niet sneller kan met behulp van modellen. In dit rapport wordt dit onderzocht.
Onderzoek Als eerste is een literatuuronderzoek gedaan naar mogelijk toepasbare modellen: • • Parametrische modellen, die met behulp van parametrische regels het uiteindelijke resultaat behalen. • • Of zelf optimaliserende modellen, welke met behulp van interne berekeningen een nieuwe constructie bepalen. De onderdoorgangen kunnen op verschillende manieren gebouwd worden. Allen hebben voor en nadelen. • • Op een traditionele manier • • Met behulp van een inschuifbaar dek • • Met behulp van een gehele inschuifbare constructie • • Een combinatie van de voorgaande Voor het model is gekozen voor een constructie met een inschuifbaar dek, omdat dit op veel plaatsen toe te passen is. Naast de bouwmethoden is onderzoek gedaan naar de werkelijkheid. Wat voor spoorkruisingen zijn er en welke moeten nog uitgevoerd worden. Dit is gedaan door de belangrijkste gegevens van een representatief spoor te analyseren. Hieruit volgen verschillende typen spoorkruisingen met het bijbehorende profiel van vrije ruimte.
interne krachten in de doorsneden ten gevolge van de belastingen wordt gebruik gemaakt van het eindige elementenprogramma SCIA Engineer. Voor de visualisatie en hoeveelheden wordt gebruik gemaakt van Civil 3D. In Excel is verder een sheet gemaakt voor de berekening van de kosten. De doorsnede capaciteiten worden gecontroleerd aan de hand van de DAKO sheets. Dit zijn gestandaardiseerde Excel sheets die doorsnede capaciteiten berekenen.
Toepassing en resultaten Om de kosten en dimensies van het model ten opzichte van de werkelijkheid te interpreteren, is het toegepast op drie onderdoorgangen (Veeneslagen, Waddinxveen en Boskoop). De resultaten benaderden de werkelijkheid tot op 15%.
Conclusie Een model is opgezet dat met behulp van een beperkt aantal invoergegevens een onderdoorgang kan dimensioneren, controleren, tekenen en beprijzen. Dit is gedaan voor onderdoorgangen en opgezet voor bruggen. De grootste problemen die zijn tegengekomen zijn het ontbreken van vuistregels. Om dit op te lossen zouden hiervoor databases aangelegd moeten worden, zodat deze gegevens snel te vinden zijn. Het model voor de spooronderdoorgangen presteert als eerste indicatie van de dimensies en kosten goed. De 15% variatie in resultaten is te verklaren. Het verschil in dimensies volgt uit de gebruikte vuistregels en cases en de afronding hiervan.
Model In het model wordt gebruik gemaakt van verschillende programma`s. Om deze allemaal te koppelen wordt gebruik gemaakt van Excel. Hierin wordt de in- en uitvoer voor en van de verschillende programma`s gegenereerd en verwerkt. Voor het berekenen van de
Student: Thesis Committee:
P. van den Noort Prof.dr.ir. J.K. Vrijling, Dr.ir. K.J. Bakker, Ir. H.K.M. van de Ruitenbeek, Ir. S. van der Woude
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
48 | Master’s Theses November 2012
3
Hydraulic Engineering
The future of the Oosterschelde with a new inlet channel
After the storm surge of 1953, the Dutch Delta project was initiated in order to protect the southwestern part of The Netherlands. A storm surge barrier in front of the Oosterschelde and various dams at the back of the estuary were constructed. These interventions led to a large change of the hydrodynamics of the Oosterschelde: a large decrease in tidal volume and flow velocities. This decrease in flow velocities caused a decrease in sediment transport from the channels with about 75%. It is estimated that an amount of 400600 million m3 of sediment is necessary to increase the flow velocities, restore the sediment transport from the channels and to obtain a new dynamic equilibrium (Kohsiek, 1987). This need for sand is called the ‘sand demand’. At present, the shoal height inside the estuary decreases by wave erosion. This decrease in shoal height mainly has a negative influence on the protected nature in the Oosterschelde. The Oosterschelde was ebb dominant and exporting sediment for centuries. All the events and interventions from 1530 up to the construction of Volkerakdam and Grevelingendam in 1969, caused an increase in tidal prism and export of sediment towards the ebb tidal delta. By the construction of the storm surge barrier, Philipsdam and Oesterdam in 1986, the situation changed, the tidal prism decreased and the ‘sand demand’ started. This research is aimed at finding a structural solution for the ‘sand demand’ by opening the storm surge barrier. The present situation of the Oosterschelde and a future situation with a new inlet channel at Neeltje Jans are analyzed in order to determine if a new inlet channel could influence the hydrodynamics and sediment transport in order to structurally solve the ‘sand demand’. A process based hydrodynamic and morphological model (Delft3D) is used to analyze the present and possible future situations with a new inlet channel. The new model and the methods of Van de Kreeke (1993) and Groen (1967) applied to the present situation of the basin, show that the Oosterschelde is still ebb dominant and would be exporting fine and
Student: Thesis Committee:
coarse sediment if the inlet would not block the sediment transport. This ebb dominance follows from the large intertidal area and deep channels. Notwithstanding the ebb dominance, there is no sediment export possible through the inlet. The inlet blocks the sediment transport in both directions mainly because of a ‘tidal jet’, caused by the small inlet and large tidal prism. The tidal prism increases with a new inlet channel and thus increases the flow velocities in the channels. The increase in tidal prism and thus flow velocities brings the Oosterschelde closer to the old situation. The higher flow velocities increase the sediment transport from the channels and thus increase the shoal building. It is not known how much the shoal building is exactly restored. Some channels have such an increase in flow velocities that shoal building occurs again. However, parts of the basin are still not in equilibrium, which can be seen from comparing the old with the new flow velocities and by comparing the tidal prism and the cross-sectional areas of the channels with the empirical relations of Louters (1998) and Haring (1976). An important disadvantage of an increase in tidal prism is the enhancement of the ebb dominance that causes more sediment transport in ebb direction. However there is no export possible through the new inlet channel, because also the new inlet channel has a ‘tidal jet’ that blocks all sediment transport through the inlet. The large-scale effects of the Oosterschelde, like the ebb dominance and ‘sand demand’ cannot be structurally changed a new inlet channel. However the shoal degradation rate will probably be slowed down with an increase in tidal prism.
R.A. de Bruijn Prof.dr.ir. M.J.F. Stive, Prof. Dr. ir. Z.B. Wang, Dr.Ir.B.C. van Prooijen, Ir. L.A. Adriaanse, Ing. S. Brasser
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
49 | Master’s Theses November 2012
3
Hydraulic Engineering
Development of a generic automated instrument for the calibration of morphodynamic Delft3D model applications
The numerical flow model Delft3D simulates the flow of water and movement of submerged sediment by means of solving simplified equations that describe these processes. Because of these simplifications, parameterizations are introduced. These parameters represent amongst others the processes that take place on scales smaller than the spacing of the numerical grid. Furthermore, parameters exist that represent measurable attributes of the system, such as the grain diameter. Lastly, scaling parameters are found in the model, with which the relative importance of certain processes in the model can be indicated. All these parameters have to be calibrated using measured data; a model application has to be tuned to produce the best fit with a set of measurements. Although calibration is an essential part in the development of any numerical flow model, no automated or standardized calibration approaches exist within Deltares. As many parameters are available within Delft3D, calibration can be a complex, time consuming process. Automated calibration is objective and can save time, whilst in the process improving the model performance; i.e. minimizing the error between the model results and the measurements. Objective of this Thesis therefore was to develop an efficient method to improve performance of and insights in the Delft3D model throughout complex morphodynamic applications. A careful reading showed that a generic open source platform for calibration of hydrodynamic Delft3D model applications already existed in the form of the software package OpenDA. This software systematically alters parameter values and compares the corresponding model results with the measurements provided. The results are judged by means of a cost function; a performance indicator which represents the goodness of fit between the model results and the measurements. OpenDA was however not yet applicable on morphodynamic model applications. Therefore, the software was adjusted, resulting in an upgraded version of OpenDA; OpenDA MOR. Apart from adding morphological parameter and -result readers, two additional performance indicators were implemented in the code; the Brier skill score and Kirchhofer scores. OpenDA MOR is suited for both calibration and sensitivity analysis of morphodynamic model applications. The OpenDA MOR calibration instrument has been tested by means of TWIN experiments. From these tests, rules of thumb have been deduced on how to apply the tool. It was shown that a calibration was most likely to succeed
Student: Thesis Committee:
when no more than 2 parameters were calibrated at once, these parameters are non-inter-related, the parameter(s) are sensitive and that the initial values of the parameters are within a 75% range of their optimum values. An extensive sensitivity analysis was performed on 17 parameters using four model applications. A large overlap in sensitivity throughout the model applications was found; i.e. the same parameters were sensitive in all model applications. Furthermore, from the parameter sensitivity, conclusions could be drawn on the relative importance of the different processes in the various model applications. Lastly, the sensitivity analysis has resulted in insights in the inter-relationships that exist between the various model parameters. After successfully testing the calibration instrument, different calibration cases have been set up to investigate two questions; can OpenDA MOR pinpoint sensitive parameters automatically? Do optimum parameter values differ for different model applications and transport formulations? It was found that automatic pinpointing was not possible, implying that a sensitivity analysis has to be performed separately before starting a calibration. From the second calibration case it became clear that different optimum parameter values were found depending on the model application and transport formula used. This shows the importance of calibration and that there is no such thing as a universal best suited calibration strategy. What parameters should be calibrated depends completely on the goal of the model; perfectly calibrated hydrodynamic parameters do not necessarily produce the best morphodynamic results and vice versa. The test results and calibration cases have shown that the calibration instrument OpenDA MOR has successfully been developed and is applicable on any morphodynamic model application. However, the applicability on complex models was shown to be difficult from a practical point of view, because of the very long runtimes of these models. Therefore, further research is needed on how to decrease the runtimes of complex model applications. Moreover, a new cost function should be developed which enables a more accurate judgment of the morphodynamic model results, as it was found that the Brier skill score and Kirchhofer scores are not suited to replace the standard cost function used during this Thesis.
R.W. Hasselaar Prof.dr.ir. M.J.F. Stive; Dr.ir. M. Verlaan; Ir. A.P. Luijendijk; Ir. S. Hummel
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
50 | Master’s Theses November 2012
3
Hydraulic Engineering
Stevin Outlet Sluices, wave impact under a beam
The Dutch department of Public Works had a problem regarding wave impacts on a beam in the Stevin outlet sluices, located in the Afsluitdijk. Wave impacts on this beam could also cause a peak pressure on the barrier gate, just behind the beam. The numerical program ComFLOW and physical scale experiments were used to predict the wave impacts for different hydraulic conditions (i.e. wave height, wave period and water level). The research questions were: 1. How is the wave load on the northern gates depending on the presence of the military beam? 2. How large is a wave impact load on the bottom of the military beam in the Stevin outlet sluices? 3. How well can the numerical model ComFLOW and physical modelling be used to determine the wave impact on the bottom of the military beam in the Stevin outlet sluices?
Physical experiments 2D scaled experiments were performed making use of a model with the (simplified) geometry of the Stevin outlet sluices and regular waves. It was found that the largest wave impacts occurred for water levels equal to the bottom plane of the beam or slightly under it. This happened for the shortest waves in the test domain. The largest pressure measured on the beam was approximately 50 kPa or 35H, with H representing the incident wave height in front of the model. It was also found that the spread in the peak pressures for one single experiment was large. The results of the measured impulse per peak showed far less spread. The effect of wave impacts under the beam was also found on the vertical wall under the beam. The actual pressures however were less and they were decreasing with increasing depth. Besides physical wave impact testing, a few experiments were performed with the beam removed from the model. This resulted in wave simply running up the vertical wall of the model. They did not cause a wave impact. The measurements of both type of experiments, with and without a beam, were compared. This revealed that the total wave impulse on the gate was not affected by the presence of the beam. However the distribution of the pressure within a single wave period was significantly different. In case of a
Student: Thesis Committee:
beam, a large impact peak was observed, whereas the other wave only showed a small hump caused by the deflected flow against the vertical wall.
Comparison with numerical model When the calculated and measured wave impact results were compared it became clear that ComFLOW underestimated the peak pressures by a factor 2 to 20 for the pressures on the impact plane. The same was done for the peak impulse. This showed that the impulse of the peak on the impact plane were underestimated by a factor 2 at most. These results confirmed that the used grid was too coarse for the program to model the physics correctly. The main conclusions to the research questions were: 1. The presence of the military beam causes a different distribution of the force on the gate within a wave period. The total amount of impulse is more or less the same as for the situation without a beam. With the military beam, a wave impact results in a peak force on the gate. Without the beam, there will be no peak force. 2. The largest measured wave impact pressure is 35H. 3. Both ComFLOW and physical modelling can be used to predict wave impacts for the geometry of Stevin outlet sluices. Much care should be taken when modelling and much attention should go to the input parameters of the program.
G.M. Hofste Prof.drs.ir. J.K. Vrijling, Prof.drs.ir. W.S.J. Uijttewaal, Dr.ir. R.J. Labeur, Ir. W.F. Molenaar, Ing. J.P. Vos, Dr.ir. P. Wellens (Deltares)
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
51 | Master’s Theses November 2012
3
Hydraulic Engineering
Numerical modelling of Colorado sandbar growth An improved formulation of sediment transport and underwater slope slumping
In the Colorado River the Glen Canyon dam is located. The Glen Canyon dam is constructed in the Colorado river for the production of electricity. Due to the dam, nowadays only a fifth of the pre-dam sediment volume flows into the Colorado River through the Glen Canyon dam and the two major tributaries, the Paria River and the Little Colorado River. Due to the lack of sediment the sandbars present in the Colorado River started eroding. An attempt to solve this problem was by mimicking the pre-dam seasonal variation in discharge. High flood experiments (HFE) were conducted in 1996, 2004 and 2008. These HFE’s were partly successful; some sandbars grew, while other eroded during the HFE. A Delft3D model of two pools and sandbars was created for a better understanding of deposition of sediment on the sand bar. The resulting modelled topography showed 5 major differences with the measured bed levels. The banks in the model were higher than in reality. The main stream width became smaller as opposed to reality. The sandbar height was overpredicted and the sandbars were growing too much into the pool. The last difference is that the model did not show an erosion hole in the main stream as was visible in the measurements. To improve the shortcomings of the model two adjustments are implemented in the model. Turbulent velocities appear to be important because surface boils were seen during the HFE. In this thesis a sediment transport formula is created, which includes the turbulent velocity fluctuations on the sediment entrainment. The second adjustment is an avalanching and slumping formulation to overcome the shortcoming related to the narrowing of the main stream and to include the slope slumps as seen at the site. These near-bed velocities are described using a probability density function, which includes the turbulent velocity fluctuations. The near-bed concentrations are calculated using the probability of occurrence of an instantaneous velocity. This probability is multiplied with the concentration corresponding to that velocity. For every instantaneous velocity in the probability density function a concentration contribution is calculated. The sum of these contributions describes
Student: Thesis Committee:
the concentration including the turbulent fluctuations. The avalanching is included by stating that no deposition can take place on slopes steeper than the angle of repose (32 degrees). Two methods are described: one where the sediment that cannot be deposited is re-suspended and one where it is transported as bed load. A third method simulates a large slope slump at a location where the bed slope was larger than the angle of repose. The slope is then changed to an equilibrium slope of 25 degrees. The sediment is transported as bed-load to the lower lying computational cells. With the inclusion of the two new formulations in the model that is applied to the Eminence pool, both formulations show to have an effect on the computed topography. When the near-bed turbulent velocities are included in the sediment transport the sandbar extends more into the pool, where the measurements show a shorter sandbar. The slope slumping method severely changed the computed topography; the Delft3D model became unstable. Both avalanching formulations showed a same influence on the final computed topography. The model results show reduced slope angles and an increase of the width of the stream. However, this is not to the extent that was measured.
B.J. Nieuwboer Prof.drs.ir. W.S.J. Uijttewaal, Dr.ir. C.J. Sloff, Dr.ir. E. Mosselman, D.R. Mastbergen
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
52 | Master’s Theses November 2012
3
Hydraulic Engineering
Golfrandvoorwaarden in havens Bruikbaarheidsgrenzen voor (numerieke) modellen
Background Hydraulic Boundary Conditions (HBC) have to be set for flood defences in harbours. In these specific areas one may account for a reduction of wave conditions relative to open sea as a result of the geometry and the bathymetry of the area. The “Voorschrift Toetsen op Veiligheid” (VTV) prescribes a scheme of three steps to determine the level of reduction that may be accounted for. Every next step in this scheme yields more specific, reliable and detailed wave conditions. One must move to the next step of the scheme when a flood defence does not satisfy the required safety standards with the loads of that step. The first step of the scheme consists of considering unreduced wave conditions and is the most conservative step. The spreadsheet model from the second step is primarily developed for simple harbour geometries. Its use is restricted by certain conditions of use. The problem of these conditions is that they are based on theory and have not yet been verified using wave measurements. It is therefore not clear where the limits of use lie for this model and when the user has to proceed to the last and most detailed step. The third step uses numerical models and there is no prescription in the VTV of which model should be used in a certain case. Every model has its own characteristics. A numerical model can therefore not always be applied in every situation to correctly calculate the reduction of wave conditions. A prescription of the limits of use of numerical models would lead to a safe and well founded choice of a model.
Research Goal
numerical model. Also, analyses have been carried out to determine the sensitivity of the (numerical) models for certain hydraulic and numeric aspects. The performances of the separate models have been assessed, based on the various cases and the sensitivity analyses. From this, limits of use have been determined.
Spreadsheet The research carried out for this project shows it is likely that the range of applicability of the spreadsheet model is wider than the present guidelines dictate. The results of the spreadsheet model turn out to be conservative in situations the model was meant for when compared with measurements or results of numerical models. Though, the spreadsheet model appears also conservative in situations it wasn’t developed for, like harbours with highly reflective boundaries and/or a lot of sheltered areas. The wider use of the spreadsheet model can save time and money by not applying numerical models.
Numerical Models A selection scheme has been derived from the limits of use of the numerical models considered. With this scheme a substantiated choice can be made between the two models. Pharos appears to be the most widely usable model. SWAN is mainly usable in harbours with an open geometry which are attacked by an irregular short-crested wave field. For this type of harbour the wave process of diffraction, which is missing in SWAN, is of less importance. In all other cases, the performance of SWAN is moderate to poor.
The goal of this project was to determine within which limits of use the spreadsheet model, Pharos (mild-slope model) and SWAN (spectral energy model) could be used for modelling wave penetration into harbours and sheltered areas and would lead to conservative results. Local wind effects have not been taken into account to be able to make an unbiased comparison between the models considered. To reach the goal of the research, the models were applied to various cases and the results were subsequently compared with results of scale model tests and results of a more detailed
Student: Thesis Committee:
S.P. Reijmerink Prof.dr.ir. T. Vellinga, Ir. P. Quist, Dr.ir. M. Zijlema, Ir. A.T.M.M. Kieftenburg, Dr.ir. M.P.C. de Jong
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
53 | Master’s Theses November 2012
3
Hydraulic Engineering
Sedimentation-velocity in jet induced flow
Research on the sedimentation-velocity of sand in the turbulent jet induced flow of a trailer suction hopper dredger while post-trenching. Embedding of subsea pipelines for protection purposes is usually done in a ‘Trench – Install – Backfill’ operation. The pipeline can also be embedded after it is installed on the seabed. This method is called posttrenching. When using a trailer suction hopper dredger for post-trenching, a large water jet erodes the soil underneath the pipe creating a temporarily trench in which the pipeline can sink. Large steel pipelines are inflexible and need a considerable free span to sink to the desired depth. The length of the trench is limited as the eroded sand that is brought in suspension starts to settle in the trench when the velocity of the suspension decreases. To be able to predict the length of the trench, the sedimentation velocity in jet induced flow is investigated in this research.
To see if the theory on the sedimentation process can represent the post-trenching process, a calculation model is made that uses the theoretical concentration profile to calculate the sedimentation velocity. A good similarity was found between the model and the experiments. The experimental research on the sedimentation velocity in a trench that is created in a post-trenching process, indicates that sedimentation velocity is largely independent of the jet parameters. To make the trench longer, it has to be deeper to lengthen the path that the bed has to travel. A test with a second run over the bed proved highly effective due to the high porosity of the sand that settles in the first run, the maximum excavation depth is twice the depth of the first run. By implementing a pipeline in the experiment it is investigated if the pipeline has an influence on the flow conditions and sedimentation velocity.
The research describes the experiment series that is performed to investigate the behavior of a trench that is created by a vertical jet flow, trailing over a sand bed. The focus is on the sedimentation part of the trench. Concentrations and flow velocities are measured to determine the shape of the trench, the distribution profile and velocity profile. The experiments show a clear relation between the depth of the trench and the length that the trench is open. A deeper trench (due to a higher pressure or lower trail velocity) results in all experiments in a longer trench. The near bed concentration and the sedimentation velocity do not change a lot for different settings of the jet.
Student: Thesis Committee:
W.J. Siteur Prof.dr.ir. C. van Rhee, Dr.ir. A.M. Talmon, Ing. M. Biesheuvel, Ir. G.L.M. van der Schrieck
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
54 | Master’s Theses November 2012
3
Hydraulic Engineering
Determining vessel motions in a harbour due to waves Using a numerical chain including a Boussinesq-type wave model
A moored vessel can experience large motions when agitated by waves. As a result, mooring lines risk breaking, the ship becomes a dangerously uncontrolled object, but most importantly unloading and loading the ship is made impossible. From an economic perspective, it is thus important to determine vessel motions due to waves at a berth. A suitable method including this in a port design would prevent an unexpectedly high inoperativeness of a built quay. The determination of vessel motion is, however, not an easy matter; wave penetration in a harbour is not easily simulated due to its complex geometry and bathymetry. This is further complicated by the high influence of low-frequency waves. These waves, especially bound low-frequency waves, impose a strict demand on the used method. The method used in the present thesis is a chain of the Boussinesq-type model Triton (Deltares) with the panelmethod diffraction model Harberth (Van der Molen) and the time domain vessel motion model Quaysim (Van der Molen). This chain adequately takes into account the non-linear wave component, having an important influence on the motion and provides a complete indication of the relevant processes, using a single model chain. An example of the aforementioned problem is the oil berth A in the Port of Leixões, Portugal. This berth experiences a mean inoperativeness of 23%. Within the present thesis, this case has been elaborated both to obtain an insight on the origin of the problem as to assess the potential of the model chain for practicedriven engineering activities. The application of the model chain has been restricted by the limited amount of available time and the results of the validation of the diffraction and motion model.
Validation results Due to a discrepancy found between the measured and theoretically expected low-frequency energy content, the wavemodel’s wave input used in the validation has been defined on the boundary using a measured timeseries. This improved the global reproduction of the low-frequency wave energy content. It is expected that the discrepancy, the high amount of low-frequency energy in the physical scale model basin, is due to the control of the wavemaker, in which this energy has
Student: Thesis Committee:
been overestimated. Using the vessel motion a priori, without using physical measurements for calibration, is limited too. The sensitivity for fender friction on the surge-motion, a very relevant motion for loading and unloading vessels, induces a high inaccuracy in case of uncalibrated settings.
Case study results The study regarding berth A, Leixões, shows that the quay is relatively unprotected for low-frequency waves. Their wave height is considerable with respect to the imposed low-frequency wave height (approximately 60%), particularly due to the profound shoaling towards the beach and the reflection off the beach.An added value of the models used in the present report has been shown by including the harbour basin of the Port of Leixões. The occurrence of seiching is recognized and spatially analysed using a method developed within this project. The energy of these eigenwaves and their nodal patterns are an indication of a significant influence of these waves on vessel motion. Finally, the wave model indicates a current caused by wave-driven setup. The influence thereof on the quay is likely, although the magnitude of this current in reality needs to be verified.
Applicability of the method The method used in the present report adequately takes into account the relevant wave processes. Vessel dynamics are properly accounted for too, allowing the inclusion of reflections off the quay wall and non-linear mooring line forces. To be applicable in practice-oriented applications, improvements of the method are necessary, especially with respect to the robustness and computational speed. Nonetheless, the method has shown its added value in the presented application.
P. van der Ven Prof.ir. T. Vellinga, Prof.ir. H. Ligteringen, Dr.ir. M. Zijlema, Ir. M. de Jong, Ir. A.J. van der Hout
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
55 | Master’s Theses November 2012
3
Hydraulic Engineering
Relative Density of a Sand Fill
The Maasvlakte II project is a joint venture between Boskalis and Van Oord. During the construction, they have measured the relative density for different kind of work methods, by making cone penetration tests. The result of those measurements is that the measured relative density for the Maasvlakte II project is higher than the values that can be found in literature for the different kind of work methods. Thus the objective of this MSc-thesis is to understand the influencing and determining processes for the relative density of dumped or sprayed sand underwater.
The work methods used for the hydraulic placement, the discharge conditions, the layer thickness, the water depth and the soil properties of the borrow area are all important in the achieved relative densities. From statistical testing, with the Kruskal-Wallis and Wilcoxon Rank Sum Test, the used work method has an influence on the achieved relative density.
This MSc-thesis can be divided in four parts. The first part describes the characteristics of sand and the relation between the density and the relative density. Laboratory testing is executed to determine the relevant parameters of the sand, such as the minimum and maximum density and the particle size distribution. The second part describes the used work methods, such as dumping, rainbowing, back filling through the suction pipe and spraying with a spray pontoon, that are used by the construction of the Maasvlakte II project. The third part describes the analysis of the CPT data. The CPT data is linked to the work methods and the relative density based on the correlations of Baldi and Lunne and Christoffersen. Also, a statistical analysis is made. The statistical analysis is based upon different kinds of statistical tests, such as Kruskal-Wallis and Wilcoxon Rank Sum Test. The last part consist of physical hypotheses that explain the potential influencing and determining processes for the relative density of dumped and sprayed sand underwater.
Student: Thesis Committee:
W.C.N. Vessies Prof.dr.ir. C. van Rhee, Ir. G.L.M. van der Schrieck, Dr.ir.P.H.A.J.M. van Gelder, Ir. M.J.M. van den Heuvel
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
56 | Master’s Theses November 2012
3
Hydraulic Engineering
Reliability of Quay Walls Calibration of Partial Safety Factors Handbook Quay Walls
A committee of Civieltechnisch Centrum Uitvoering Research en Regelgeving (CUR) is currently (2012) working on the update of the handbook Quay Walls (CUR 211). In the past the partial safety factors in this book were derived using a spring model, but new developments enable to use Finite Element Methods (FEM) to model sheet-pile structures and quay walls with relieving floor. The main objective is to use FEM (in this case PLAXIS) to calibrate the partial safety factors. To fulfil this objective, level II probabilistic calculations (FORM) are performed using Prob2B (a toolbox from TNO) to define influence coefficients for the different parameters and reliability indices for the different failure mechanisms. This is done for two benchmark quay walls: an anchored sheet-pile and a quay wall with relieving floor. Both are designed according to the FEM design guidelines in CUR 166, the handbook on sheetpile structures. Furthermore, the calculations require coefficients of variation for each stochastic parameter, correlation coefficients and definitions of Limit State Functions. These are all derived and presented in the report. With the output of the level II calculations, a level I method is used to define the partial safety factors and besides the design procedure of CUR 166 with FEM is evaluated and suggestions for adaptation for quay walls with relieving floor are presented.
The main consequences according to the output of the probabilistic FEM calculations are: • • Higher partial safety factors on the internal angle of friction and stiffness parameters of the soil • • Lower partial safety factors on the geometrical parameters (retaining height, water levels) • • Mean values for cohesion, sheet-pile parameters and anchor diameter • • Changes in fault tree for quay walls with relieving floor • • Adaptation of the in the handbook sheet-pile structures (CUR 166) prescribed calculation method using FEM for quay walls with relieving floor (CUR 211) • • Additional effort in the research and calculations of other quay walls • • Standardization of probabilistic calculations or sensitivity analysis in quay wall design
Student: H.J.Wolters Thesis committee: Dr.ir. K.J. Bakker, Dr.ir. R.B.J. Brinkgreve, Dr.ir. J.G. de Gijt, T. Schweckendiek, Prof.drs.ir. J.K. Vrijling, Prof.ir. A.C.W.M. Vrouwenvelder
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
57 | Master’s Theses November 2012
3
Hydraulic Engineering
Innovative design for lock gates Curved sliding gate
Design of a lock gate for Nieuwe Zeesluis in IJmuiden becomes a challenge when the boundary conditions limit the choice for the conventional types of the gate. All the initial efforts of this study have been made in search of a new alternative to solve the space limit problem. Finally, when the curved gate concept was introduced based on the concept of rolling gates and sliding gates, all the functional requirements of the design had to be met. This study will discuss the approach and steps in which the idea was developed and investigates in three different structural alternatives for the curved gate in the concept development stage. Based on certain design objectives, a final innovative concept is chosen and is developed into a preliminary design. The main challenge in the conceptual design is to find the optimum combination within the alternatives for the main compartments of the gate. Every advantageous solution for a compartment, introduces a new problem in another.
Student: Thesis Committee:
After an integrated and consistent conceptual design is provided, the study presents a rather detailed design of certain compartments such as operational equipment, guidance devices, tracks, hydraulic bearings and sealing system. Structural and stability checks for the extreme load cases, construction and during the special combined movement of the gate provide necessary information which result in a preliminary design. The preliminary design stage ends by evaluating the feasibility of curved sliding gate concept. The final and most important evaluation of the research study discusses the costs, safety, reliability and availability of the gate structure. A qualitative RAMS analysis accompanied by a cost comparison table provides insight on applicability of the gate into the different situations but especially in this case study. The answer to the applicability question is the highlight of the outcomes within the conclusions of this graduation work.
S. Zel Taat Prof.drs.ir. J.K. Vrijling, Ir. A. van der Toorn, Ir. R. Abspoel, Ir. W.P.J. Langedijk, Th. P.M. van der Tol
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
58 | Master’s Theses November 2012
3
Hydraulic Engineering
Upflow limestone contactor for soft and desalinated water
Desalinated or demineralised water or even soft water is characteristically low in hardness, alkalinity and pH. Thus, these kinds of water need to be re-conditioned (re-mineralized) before distributing for usage as drinking water. The produced water is expected to satisfy the following requirements: safe quality for human health, no quality change during distribution and no demolishing of the distribution infrastructure (no corrosion or excessive scaling). In order to achieve both targets, the water alkalinity, pH and calcium saturation level must be considered as the three main parameters in re-mineralization process. In general, limestone contactors are frequently used for increasing these three parameters before the water can be distributed. This technology should be considered as one of the most popular conditioning techniques used in drinking water treatment field nowadays. Typical examples are limestone contactors of Ashkelon Desalination plant in Israel, Larnaka sea water reversed osmosis (SWRO) plant in Cyprus and Barcelona SWRO plant in Spain. In fact, the determining factor for remineralized water quality is the kinetics of limestone dissolution. There are several theoretical models (PWP, Chou) as well as practical models (Dreybrodt) to describe the calcite dissolution kinetics. However, the theoretical models tend to idealize the real kinetics in practice while the empirical models are not systematic and constituent to be widely applied. Consequently, this study would mainly focus on developing the two popular theoretical kinetics models (PWP and Chou) to a practical model with theoretical basis that could fully capture the practical calcite dissolution kinetics. On top of that, a layer model concept would be introduced as the base for further developing the downflow and upflow limestone contactor model. Subsequently, simulated results indicate that upflow model is technically more superior to downflow hence providing more economical benefits as well. Vosbeck, Anderlohr’s experiments as well as the marble filtration recorded data at Hoenderloo pumping station of Vitens (Netherlands) would be utilized for building and verifying models throughout this research. In the end, an optimal design would be introduced for the reminer-
Student: Thesis Committee:
alizing process at Hoenderloo marble filtration with the aim to increase the filtering capacity, effluent quality and reducing the operational costs at the same time. In addition to the technical research, a computer based program was built in Excel application with PHREEQC embedded, which includes all of the developed kinetics models for calcite dissolution. The program is developed in order to assist the users as an accurate yet handy tool for quickly predicting or simulating certain calcite dissolution kinetics.
P.B. Do Prof.dr.ir. W.G.J. van der Meer, Ir. P.J. de Moel, Dr,ir. J.Q.J.C. Verberk, Dr.ir. P.J. Visser, Y.P. Lin
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
59 | Master’s Theses November 2012
3
Hydraulic Engineering
“Traffic induced vibration in floating thoroughfares” (Vibraties in drijvende wegen als gevolg van het verkeer)
De ontwikkeling van drijvende constructies bevindt zich momenteel in een stroomversnelling. De drijvende kracht hierachter is de alsmaar toenemende druk op de openbare ruimte die het gevolg is van de verwachte zeespiegelstijging en de volksmigratie naar de waterrijke (kust-) gebieden. Logischerwijs vindt de ontwikkeling plaats binnen de woningbouwsector en de kust- en havenbouw, maar wat mij betreft mag daar binnenkort de wegenbouw aan worden toegevoegd. De drijvende weg die ik gemodelleerd heb maakt onderdeel uit van het Nederlandse hoofdwegennet dat door drassig gebied voert, dat wil zeggen: over land met een hoge grondwaterstand en slappe bodem zoals dat veelal voorkomt in het westelijk deel van Nederland. De weg is enkelbaans en bestaat uit een serie geschakelde, drijvende elementen (pontons). Elk element is rechthoekig van vorm. Onder invloed van het verkeer zal de weg verticale uitwijkingen vertonen. Factoren als wind en golven mogen geen rol van betekenis spelen omdat ze een te grote invloed zouden hebben op de beweging waardoor de veiligheid van de gebruiker en de begaanbaarheid van de weg ernstig in het gedrang komen.
Uit het onderzoek is gebleken dat uitgaande van elementen met een soortelijke massa van 102.5 kg/ m 3, een breedte van 5.4 meter en een hoogte van 1.6 meter, minimaal een lengte van 4.5 meter nodig is om verkeer met een snelheid van 120 km/u veilig en comfortabel te kunnen faciliteren. Voorwaarde is wel dat de verbindingen tussen de elementen bestand moeten zijn tegen ongeveer 40 kN. Verder toont het onderzoek aan dat in theorie resonantie niet is uit te sluiten, maar wel effectief kan worden onderdrukt. Dit kan bijvoorbeeld door de lengte van de elementen te vergroten tot 5.5 meter. Hierdoor is er voldoende tijd (halve minuut!) om te anticiperen op zo’n gevaarlijke situatie. Behalve verlenging is verzwaring van de elementen ook mogelijk. Helaas gaan beide aanpassingen ten koste van de transporteerbaarheid. In de ontwerpfase zal naar een goede balans moeten worden gezocht tussen veiligheid en transporteerbaarheid.
Ook zonder de invloed van wind en golven kunnen significante uitwijkingen worden “opgewekt”; binnen mijn afstudeerproject hebben ik (model)onderzoek gedaan naar de grootte van de uitwijkingen ten gevolge van verkeer. Maatgevend voor het onderzoek is het fysieke fenomeen van de “impact” –achtige uitwijking die ontstaat wanneer een voertuig de weg oprijdt en, als de weg lang genoeg is, de resonantie die kan ontstaan wanneer voertuigen zich voortbewegen met een snelheid die dicht bij de voortplantingssnelheid ligt van de verticale golf in de serie drijvende elementen. Het model is overigens zodanig ontworpen dat de verbindingen deze vibraties moeten kunnen reduceren.
Student: Thesis Committee:
E.J. Kaspers Prof.drs.ir. J.K. Vrijling, Prof.dr. A.V. Metrikine, Dr.ir. W.G.M. Groeneveld, Ir. W.F. Molenaar.
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
60 | Master’s Theses November 2012
3
Hydraulic Engineering
Sustainability as a Procurement Criterion for Port Investments
Many industries are already aware of the fact that they can gain higher profits by integrating sustainability within their management process. The construction industry seems to be a late developer. Lately, port authorities have started many initiatives for a more sustainable port. To make ports more sustainable it is worthwhile to improve the construction of infrastructure and building projects: the construction industry is still one of the most polluting industries. Hence, in this thesis the answer is given to the question of how to integrate sustainability as a procurement criterion for infrastructure projects in ports. This is done by developing a procurement model which is aimed at sustainable procurement. Sustainability is important for a port: the amount of total environmental space is decreasing due to stricter policies. To enable further growth of port activities, sustainable management is inevitable. A more sustainable port results in a larger public support for port activities. Furthermore, sustainable management can result in lower costs due to a higher efficiency in the business activities.
flexibility, stability, effectiveness and user-friendliness. Beside it evaluates the scoring on weighted criteria (concordance), the concordance method evaluates how low the alternative scores for a good balance between the criteria. This is how this method distinguishes itself in a positive way. The criteria with the evaluation method form the model and it is applied on three different projects for the construction of quay walls in the port of Rotterdam. There was a clear differentiation between the alternatives in the outcomes, in an appraisal was made between sustainable criteria and investment costs. The model is applicable in different phases in the tender process. The scores on concordance and discordance give extra information about the foundations of the outcomes of the tender, which is an advantage of the method.
It is important that the port authority chooses for a contracting form that allows enough space for the contractor to deliver a sustainable construction. This is possible with innovative contracting forms such as D&B contracts in contrast to traditional contracting forms. The right procurement procedure is important too. The model includes criteria and an evaluation method. These criteria are set based on interviews with stakeholders and literature search. Those can be categorized in the fields People, Planet and Profit. It is essential to apply Life Cycle Analyses with a preference for quantification of criteria e.g. emission footprints. In practice this is almost impossible due to the complex computations which contractors have to do. That is why the applied model is different from the ideal model, because there is chosen to assess the different measures in a qualitative way on 1) how specific, measurable, acceptable, realistic and time bounded the measures are and on 2) the impact during the whole Life Cycle of the construction. The alternatives are evaluated with the concordance method. This method is emerged as the most suitable based on applicability, transparency,
Student: Thesis Committee:
E.F.M. Broesterhuizen Prof. T. Vellinga, Ir. L. Docters van Leeuwen, Ing. J.W. Zwakhals, Ir. P. Taneja, Dr. M. Nijdam, Dr.ir. R.J. Verhaeghe
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
61 | Master’s Theses November 2012
3
Hydraulic Engineering
The influence of the wave height distribution on the stability of single layer concrete armour units
The dimensions of single layer concrete armour units (interlocking armour units) are calculated with a similar stability relation as the stability relation for quarry stone. In these design formulas an ‘average/significant’ wave load is used (Hs). Since quarry stone gains its stability only from gravity, this type of armour unit is constructed in a double layer and therefore some damage development is allowed. Interlocking armour units are constructed in a single layer and the design should be based on zero damage. This research investigates whether this different approach to damage leads to a different characteristic design wave load which will increase the accuracy of the design method for interlocking armour units. It is focussed on the influence of the wave height distribution on the stability of single layer concrete armour units in general and Xbloc in particular. For Xbloc, zero damage is defined as a criterion for rocking of the armour units: during design conditions “not more than 2% of the units are allowed to move during more than 2% of the waves”. To find a stability relation based on this criterion, the stability of Xbloc is investigated according to rocking of armour units contrary to the conventionally approach to stability based on the number of displaced units from the armour layer.
Student: Thesis Committee:
To find the relation between waves and rocking, physical model tests are performed. In these tests a model breakwater is loaded by wave series with different wave height distributions, wave steepness and groupiness. It resulted that every wave has a certain probability of causing rocking of an armour unit. This probability of rocking is mainly dependent on the height of individual waves and to a lesser extent on the groupiness of the wave series. The steepness of the waves appeared to have a negligible small influence. When the found rocking probability relation is combined with the criterion for rocking, it appears that H2% is mathematically a better fitting parameter for a stability relation according to rocking. A new stability relation for Xbloc is derived based on H2%. Additionally, it is found that very extreme wave heights can dislodge an armour unit in such a way that this armour unit does not interlock anymore. Because it is undesirable that armour units do not interlock anymore, dislodgement of armour units should be accounted for in the stability calculations. Therefore, also a stability relation based on dislodgement of units is provided.
S.A.A. Zwanenburg Prof.dr.ir. W.S.J. Uijttewaal, Dr.ir. G.P. van Vledder, Ir. H.J. Verhagen, E.Ten Oever
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
62 | Master’s Theses November 2012
3
Hydraulic Engineering
Simulating Barrier Island Evolution Coupling Process-Based Models
Barrier islands are important features in the coastal zone, among others because they shelter the mainland from waves and storm surge. Thus, the degradation of barrier islands can pose a threat to coastal safety. Hence, there is a societal demand for understanding and predicting barrier island evolution. High energy events, such as storms and hurricanes, play an important part in this evolution, with hydraulic sediment transport causing large and rapid changes in morphology. In the periods between storms, (partial) barrier island recovery takes place, largely driven by aeolian sediment transport on longer timescales. Hence, when predicting the morphological development of barrier islands, both hydraulic and aeolian transport need to be taken into account. Also, both the event timescale of hours to days, and the recovery timescale of weeks to months need to be resolved. Currently, no single numerical model exists that simulates both hydraulic and aeolian transport, though there are models that resolve either one separately. So, to resolve both simultaneously, twomodels will have to be coupled. The above leads to the two objectives of this thesis; firstly, constructing a coupling between a hydraulic and an aeolian sediment transport model, and analyze physical and numerical aspects of the model interaction. For this purpose the models XBeach and Dune are selected. The coupling is created using the Earth System Modelling Framework (ESMF). The second objectiveis confirmation of the predictive skill of the coupled model for the evolution of a real barrier island. Assateague Island (MD, USA) is selected, and a combination of model skill score and bias is used to represent the predictive capabilities of the coupled model. From a process point of view, undertow, long wave flow, and increased turbulence due to wave breaking have a significant effect on the sediment transport during storms, and all are represented within the XBeach model. Aeolian transport is less important during storms, because the sand supply is limited by submergence and moisture content.
Student: Thesis Committee:
During recovery, aeolian transport does play an important role in transporting the sediment towards the beachand dunes, where it is often trapped by vegetation. The lower wave height during these periods allows for a relatively larger influence of short wave asymmetry, that can lead to hydraulic transport towards the shoreline, creating a sediment supply for beachand dune recovery. This makes the foreshore zone an interface between hydraulic and aeolian processes. The coupling between XBeach and Dune allows the models to exchange information after every communal timestep, thus facilitating dynamic interaction. This is only necessary when simulating recovery periods, for the influence of aeolian transport during storms is assumed negligible. The structure of the ESMF makes it possible to couple multiple models together, requiring only a few adaptations to the structure of the sub-model codes. This also provides the flexibility to add new or replace old models with relative ease. To confirm the predictive skill of this coupled model, a hindcast of six months of morphological development of Assateague Island will be performed. To this end,storms are distinguished from recovery periods, and are simulated in chronological order, the former with XBeach, the latter with the coupled model. The simulations lead to negative skill scores because of a significant overestimation of storm induced erosion. Even when using an overwash sediment transport limiter to reduce the erosion during storms, the skill scores remain negative. It can be concluded that the first objective has been fulfilled, since a coupling between XBeach and Dune has been constructed. Although a hindcast was performed, this could not confirm the predictive skill of the coupled model, so the second objective was not completed.
J.P. den Bieman Prof.dr.ir. M.J.F. Stive, Dr.ir. J.S.M. van Thiel-de Vries, Drs. F. Baart, Dr.ir. A.R. van Dongeren, Dr.ir. J.E.A. Storms
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
63 | Master’s Theses November 2012
3
Hydraulic Engineering
RAMSSHEEP analysis: a tool for risk-driven maintenance Applied for primary flood defence systems in the Netherlands Introduction Floods are a threat to millions of people who live in lowlands like the Netherlands. Therefore the Dutch government has been given requirements for primary flood defence systems like dikes. The current condition of most of these dikes does not fulfill to these requirements based on flood risk analyses of RWS. The most logical step is to take measures by constructing new structures or planning regular maintenance activities over time. It is most commonly used to focus on economical most beneficial measures and maintenance intervals for a primary flood defence system like the Afsluitdijk.
Research goal RWS aims to launch a certain risk-driven maintenance concept named RAMSSHEEP which should be developed by the current market. The objective is to assess whether or not RAMSSHEEP can be applied as a risk-driven maintenance tool for primary flood defence systems based on the results of the existing method of Probabilistic Approach. By describing the two approaches of a flooding problem more insight will be gained in the advantages and disadvantages of RAMSSHEEP.
Methodology and approach
Moreover, it is not always profitable to take such investments in an existing system. Therefore maintenance can be applied to decrease the probability of occurrence temporarily. Dominant failure events have been approached by describing scientific deterioration models which illustrates decrease of strength over time. A maintenance optimization describes the most economical beneficial time intervals in which maintenance should be applied based on the deterioration model. Eventually these results form the basis for the translation to RAMSSHEEP requirements. This result illustrates which requirements have been used and which not. This comparison (Probabilistic Approach vs. RAMSSHEEP) gives more grip on the assessment of the correctness of RAMSSHEEP as a risk-driven maintenance tool in the hydraulic engineering.
Conclusion and recommendation The probabilistic analysis always gives the most economical beneficial solution which forms the main driver of all the problems in society. RAMSSHEEP has proven not to be able to use as a risk-driven maintenance tool with economics as the main driver. By combining the probabilistic analysis and maintenance optimization, it is recommended to apply a new given model named EMAR.
A general flooding problem has been approached by analyzing the system on its main functions. Sub-sequently, a probabilistic analysis has been made by estimating the possible damage and its annual probability of occurrence which together lead to the monetary risk. To decrease this probability of occurrence some measures can be taken which will cost a certain amount of money. Eventually these investments will be analyzed whether or not this amount is lower than the expected level of damage in the old situation, so is the criterion of gaining safety larger than the improvement costs met?
Student: Thesis Committee:
W. Wagner Prof.dr.ir. J.K. Vrijling, Dr.ir. P.H.A. J.M. van Gelder, Prof.ir. A.C.W.M. Vrouwenvelder, Ing. R.E. Peterse, Dhr. B. Maas
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
64 | Master’s Theses November 2012
3
Hydraulic Engineering
The morphological impact of the deepening of the deep foreshore on the Dutch coast
The deep foreshore is the part of the cross-shore profile that is between 8 m and 20 m deep. Indications exist that this area might be deepening. In this report the long term morphological consequences of this possible trend on the sandy coast of Holland (the stretch between Hook of Holland and Den Helder, excluding artificial defences) are discussed. It is assumed that the deep foreshore is deepening at a rate of 2 cm a year. Two scenarios, representing the hypothetical situation after 50 and 100 years, namely, scenarios where the deep foreshore has deepened 1 metre respectively 2 metres, are compared to the scenario where the deep foreshore does not deepen – more or less the actual situation. Six locations, spread along the sandy coast of Holland, are subjected to calculations to determine the effect that deepening of the deep foreshore has on the sandy coast of Holland. The focus is on three morphological aspects: 1. Dune erosion and extent of area of offshore deposition of sand storm surge. The process-based DurosTA model is used for calculations. The sandy coast is subjected to a storm surge with wave heights and water levels reaching maximum design values. The calculations show that dune erosion during storm surge does not significantly increase as a result of the deepening of the deep foreshore. The area of deposition – the extent to which sand is deposited offshore during a storm surge – increases slightly due to deepening of the deep foreshore. 2. Longshore transport The impact of deepening of the deep foreshore on the Dutch coast is determined by calculating the longshore transport created by two wavetypes, that together form a couple that is representative for the morphologically relevant wave types along the sandy coast. The process-based Unibest LT model is used for calculations. The Van Rijn formulation of sediment transport is applied.
Student: Thesis Committee:
Increases of longshore transport vary between 3 to 8%, depending on the waveheight and angle of incidence. The increase of longshore transport is assumed to be proportional to the increase of longshore transport gradients along the sandy coast of Holland. 3. Cross-shore transport The process-based Unibest TC model is used for the calculations. Unibest TC is capable of simulating the various processes that contribute to sediment transport such as streaming, wave asymmetry, undertow and long bound waves. Deepening of the deep foreshore leads to an overall clear seaward shift of calculated transport rates in the order of several cubic metres per year per running meter (m’) of coastline. General conclusion: altogether, these effects are limited when put into the perspective of the yearly volume of suppletions that are required now and in the future. However, they would be lasting and would endure many decades.
T. van Walsem Prof.dr.ir. M.J.F. Stive, Ir. C. den Heijer, Dr.ir. P.J. Visser, Drs. N. Geleijnse
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
65 | Master’s Theses November 2012
3
Hydraulic Engineering
66 | Master’s Theses November 2012
3.a Civil Engineering theses
Hydraulic Engineering – COMEM Domain Coastal and Marine Engineering and Management
3a
Hydraulic Engineering – COMEM Domain
Calculation of Wave Forces using REEF3D
Non-breaking wave forces on a cylindrical pile are calculated numerically by solving the three-dimensional Navier Stokes equations in the numerical wave tank of REEF3D. Initially, the numerical wave tank is validated by comparison of the numerical results with the analytical solutions for varying grid density, time step size, numerical beach width, wave amplitude, numerical methods- time and spatial discretization, relaxation method and wave type. The performance of the wave tank under the aforementioned various conditions is observed. As a result the appropriate parameters to be used for the numerical experiment are obtained. Finally, simulations are carried out to calculate the wave forces on a cylindrical pile and the numerical results are compared to the results obtained using the Morison formula. During validation, it is observed that the wave tank gives good results with an error of 0.24% in the wave amplitude at a grid density of 100 cells per wavelength and CFL number 0.1 for a fifth order Stokes wave of amplitude 0.05m and wavelength 2m. A recent study using a different approach reported a requirement of 200 cells per wavelength. Thus, the performance of the wave tank in this study is considered very good. The calculation of wave forces also shows promising results. The wave forces from REEF3D seem to be slightly under estimated compared to the Morison force in the four numerical experiments carried out. There exists a possibility of erroneous calculation of the Morison force. There were no instabilities in the solution from the numerical calculations. Due to the absence of simple experimental data for wave force on a cylinder and time constraints, validation is attempted only through Morison formula by adding the formula in the code. The validation of wave force calculation could not be deemed conclusive.
Student: Thesis Committee:
A.M. Kamath H. Bihs
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
68 | Master’s Theses November 2012
3a
Hydraulic Engineering – COMEM Domain
One-Dimensional Viscoelastic Simulation of Ice Behaviour in Relation to Dynamic Ice Action
The goal of this work was to simulate the behaviour of ice under cyclic loading. The linear viscoelastic Kelvin, Maxwell and Burgers models were implemented in Matlab by means of The Boltzmann superposition principle. This method was verified using cases which could be represented by analytical solutions. During the extensive sensitivity analysis carried out, it was determined that the ratio n/(fλ) influences the shape of the strain response curve in a creep test for all of the models considered in this study. With the knowledge of parameter n/(fλ), preliminary conclusion on the result of the test can be drawn. The change of the second modulus is defined by the Kelvin unit which determines the delayed elastic deformations. The time required for these deformations to fully developed is given by 5λ2. The changes in the value of the second modulus occurs only before this value is attained. However in linear viscoelastic Burgers model, this change is relatively small . This is because the Maxwell unit in the Burger model has a major influence on the shape of the stress-strain curves. Available literature was used to obtain the input parameters for Burgers model for ice. They were obtained by calibration of the model data with the experimental data presented therein by producing a best fit curve. Since this study utilized a non-linear model to replicate the experimental data, it was also used to compare the results of a linear model with a non-linear model. The region conforming to the delayed elastic deformation was not represented accurately by the linear model. Uniaxial cyclic compression test performed at UNIS was modeled using the linear viscoelastic Burgers model using the scaled down input parameters obtained through calibration with fresh ice creep test to enable their application to this case. The viscoelastic model was unable to completely agree with the findings from the test carried out at UNIS.
Student: Thesis Committee:
M. Yazarov Prof.dr.ir. M.J.F. Stive, K. Høyland
For further information please contact the section Hydraulic Engineering, 015-2783348 Email:
[email protected]
69 | Master’s Theses November 2012
3a
Hydraulic Engineering – COMEM Domain
70 | Master’s Theses November 2012
4. Civil Engineering theses
Geo-Engineering
4
Geo Engineering
Floating Piles An investigative study into the behavior of friction piles within a settling soil profile Loading of a highly impermeable soft soil substratum, like the placing of an artificial island on a marine clay or road construction on peat soils, will cause consolidation leading to settlements. Due to the impermeability of these soils consolidation can take years to complete. Extra loading, i.e. buildings or other facilities, will cause even more compression of the soil causing differential settlements. Differential settlements cause large damage and mitigating measures are difficult and costly. One of the measures to prevent these differential settlements from occurring is the use of settlement reducing piles. These piles are not placed on a bearing substratum but are installed in the settling soil profile. This will cause to piles to settle together with the soil. Different uncertainties in these so called “floating piles” are the amount of settlement the soil shows. This is the driving mechanism in the problem. Because the soil will both load and support the pile it is important to have a good image of the subsoil reaction, both over the depth of the stratum as well as its reaction in time. Besides this another important uncertainty is the interaction between the pile and the soil. The strength of the interface between the pile and soil varies depending on soil type, pile material and depth of the pile. Load - displacement curves can be determined at different depths to make an evaluation of the stresses in the piles and the amount of settlement caused by the loads.
Student: Thesis Committee:
This entire study will be split up into two separate parts. This study, which is the first part, will focus on the settlement of the soil profile and its modeling this in a geotechnical centrifuge. The centrifuge is used to scale up the dimensions of the sample, and scale down the consolidation process. The amount of settlement occurring due to this consolidation is predicted with different calculation methods and checked with centrifuge tests. The next part of the research will focus on the interaction between pile and soil, including centrifuge tests.
friction pile in a settling soil profile
J.G. Bol Prof.ir. A.F. van Tol, Dr.ir. K.J. Bakker, Dr.ir. J. Dijkstra, ing. H.J. Everts, Dr. M. Cunningham
For further information please contact the section Geo-Engineering, 015-2781423 Email:
[email protected]
72 | Master’s Theses November 2012
5. Civil Engineering theses
Watermanagement
5
Watermanagement
Pluvial flood damage modelling. Assessment of the flood damage model HOWAD-PREVENT
Introduction
Results
Flooding is a natural phenomenon, but human activity has significantly altered the natural drainage processes thereby occasionally causing greater flood risk. Urban flooding has become more frequent due to a number of factors including climate change, urban growth and an increase in paved surfaces. Pluvial flooding results from heavy rainfall when water that does not infiltrate into the ground ponds in hollows or flows over the ground. In flood damage estimation, the concept of damage curves or damage functions is applied. Such functions give the building damage due to inundation. Most damage assessment models have in common that the direct monetary damage is obtained from the type of the element at risk and the inundation depth.
Problem definition Flood damage assessment models do not focus solely on pluvial flood damage estimation. In addition, the existing flood damage models and developed depth-damage curves have not been tested for application of pluvial flood events.
Research
Results show that there is significant increase in the number of flooded buildings and consequently the damage with a water level increase of each 0,1 m step meaning that the model estimates are sensitive to water level changes. As expected, there is difference in damage estimates, if two different depth-damage curves are used.
Conclusions and recommendations The model can be successfully used for pluvial flood damage assessment. The main uncertainty sources of the HOWAD-PREVENT are all input data sources – water level, building stock classification and depth-damage curves. While building classification has the least influence on the uncertainty, both water level and depthdamage curves have the most influence. Some of the recommendations for model adjustments include relative depth-damage curve development especially for pluvial flood events and automation of the building stock analyses. Recommendations for further research are model validation by comparing model outcomes with insurance company payouts.
This study is carried out with the main objective to test the flood damage assessment model HOWAD-PREVENT in a case study in Rotterdam and to evaluate the uncertainty and sensitivity of this model. The model applicability and sensitivity was tested by running the model with two building type files together with three water level files.
Student: Thesis Committee:
L. Sterna Prof.ir. F.H.L.R. Clemens, Dr.ir. J.A.E. ten Veldhuis, Dr.ir. O.A.C. Hoes, Ir. M.H. Spekkers
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
74 | Master’s Theses November 2012
5
Watermanagement
On the Topographic Classification of the Chemoga Watershed, Ethiopia
The applicability of recently developed landscape classification system that uses height above the nearest drainage (HAND) and slope was tested for the Chemoga basin located in east Africa, Ethiopia, than the place it was developed for. Besides that the sensitivity of HAND and slope for various inputs in the landscape classification model and location of the observed data used for the calibration of HAND and slope, were tested. Using the threshold Hand and slope the catchment was grouped into three distinct runoff generating units, i.e. wetland, hillslope and plateau. The equifinality of the threshold HAND and slope that helps to classify the catchment into these landscape units decreases as we use observed data collected from the boundary between different landscape units. In addition, having enough hydrotope data from all hydrotope units lower the discrepancy caused by not having the right flow initiation area threshold and insulates the problem of having misinterpreted observed data. Hence similar landscape unit in most part of the world exhibit similar runoff generating property having the right frame work to collect data to classify the basin into these units will make the communication between hydrologists easy.
Student: Thesis Committee:
F.B.M. Desta Prof.dr.ir. H.H.G. Savenije, Prof.dr. S. Uhlenbrook, Dr. M. Hrachowitz, Dr. Y.A. Mohamed
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
75 | Master’s Theses November 2012
5
Watermanagement
Cold CANON: Anammox at low temperature
Introduction
Result
The process of one-stage partial-nitritation and Anammox system can be called CANON. Although CANON has many advantages over traditional N removal methods, CANON needs high temperature (around 30℃) to operate. So if CANON or Anammox in CANON can work at low temperature, this innovative technology can also be applied in mainstream WWTP, which will make WWTP more cost-efficient and sustainable. CANON at low temperature would be the focus of my thesis. I did my research in cooperation with Environmental Biotechnology department and my lab experiments were also done there.
1. Through lab experiments, ways of limiting NOB activity (by lowering DO) and remaining high AOB activity (by setting an appropriate DO) and Anammox activity (by setting an appropriate DO and pH, ensuring enough N load, controlling low shear stress and low NO 2- concentration in the bulk, keeping a short SRT which didn’t washout Anammox) at 15 ° C were found. 2. Through model simulation, mainstream CANON had smaller energy consumption, less footprint and better effluent quality, so its application would be costefficient for Dokhaven WWTP.
Conclusions and Recommendations
CANON or Anammox at 15 ° C can have a good performance (with TN removal efficiency of more than 60%) in lab-scale as long as suitable operating conditions were supplied. The suitable operating conditions were determined by understanding granular sludge structure and bacterial characteristics and by lab experience. Based on the model simulation and balance calculation of N and energy, the mainstream CANON would be very promising to Dokhaven WWTP.
Research My research focused on how AOB, NOB, Anammox competed with each other and develop themselves in granules at low temperatures (mainly at 15 ° C) under different operating conditions. The whole research was divided into two parts: 1. Lab experiments: to obtain the overall N removal efficiency of the system, activities of AOB, NOB and Anammox, and morphology of granules under different operating conditions at 15 ° C. 2. Model simulation: to know the impact on energy consumption and N removal efficiency of the implementation of mainstream CANON in Dokhaven WWTP.
Student: Thesis Committee:
C. Fei Prof.ir. J.B. van Lier, Prof.ir. M.C.M. van Loosdrecht, Dr.ir. M.K. de Kreuk, Dr.ir. R. Kleerebezem, Dr.ir. H.L.F.M. Spanjers, Ing. T. Lotti
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
76 | Master’s Theses November 2012
5
Watermanagement
Judgment under Uncertainty A Probabilistic Evaluation Framework for Decision-Making about Sanitation Systems in Low-Income Countries Introduction
Conclusions and Recommendations
Sanitation, as described by the World Health Organization (WHO), refers to the provisions of facilities and services for safe disposal of human urine and faeces. On the outset of the 21st century, 40% of the world’s inhabitants do not have access to sanitation facilities and still rely on a bucket, a bush or a backstreet for excretion. Technically, all options that are required to deal with the global sanitation problem seem to have been already developed. However, the challenge remains in selection and implementation of technologies in a way that the desirable outcomes would be resulted. Some decision-making support tools have been developed so far to address this problem by assisting the decision-makers in selecting the appropriate technologies. While decision-making is about considering the likelihood of uncertain events, in most of the existing evaluation approaches the complex task of predicting and evaluating probabilities is reduced to simple judgmental operations. For instance, evaluation of sanitation options is often performed based on predicting the outcomes that best represent a sanitation system, with no or little regard to the factors that limit the predictive accuracy.
By applying the probabilistic evaluation approach for decision-making about sanitation facilities in lowincome unplanned slum settlement of Nyalenda in Kisumu, Kenya (based on limited available data about this region in literature) it is indicated that while a sanitation option may be known for fulfilling a certain task by definition, through a probabilistic evaluation it may be revealed that the local conditions are not likely to allow the expected outcome to occur in practice and as a result this option would have no priority among other options. The necessity for monitoring and post-evaluation of implemented sanitation projects in order to have sufficient feedback for improvement of future decisions is also highlighted.
Research This thesis adopts a new evaluation approach by taking into account the real world examples from executed sanitation facilities and develops a probabilistic evaluation framework in which sanitation options are assessed based on the probabilities that specific outcomes occur in practice. Absolute judgments are replaced by probable assessments, as this approach tries to keep its distance from making the uncertain certain. Although there may be a hidden consensus that quantification of occurrence probabilities for various outcomes of sanitation options is not always possible, some quantification methods are developed and presented in this thesis for all the assessment criteria. Moreover, this thesis does not only focus on making the decisions, but also tries to channel the decisions in a way that the negative outcomes of sanitation facilities would be reduced through the measures that could be taken to improve the performance of sanitation options.
Student: Thesis Committee:
S. Malek Pour Prof.dr.ir. J. van Lier, Prof.dr.ir. F. Clemens, Dr.ir. J. Langeveld, Ir. Laura Talsma
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
77 | Master’s Theses November 2012
5
Watermanagement
Innovative Design of Gully Pot for Preventing Big particles Clogging Problem
Introduction
Conclusions and recommendations
Gully pots or roadside catch basins are a common and important part of sewerage drainage networks. Their primary function is to retain larger solids from road runoff. They are used to minimize the problems associated with sediment in downstream drainage structures, pumps, treatment plants and receiving waters.
Problem definition Gully pots clogging problems have gradually been recognized over recent years. Blockage of inflow devices (especially gully pots) is the most frequent cause of flooding, for flooding of buildings and of roads. Gully pot blockages cause the highest numbers of flood incidents and are subject to larger uncertainty than other basic events.
The gully pot clogging problems can be improving by new alternatives design. And the results show that big size of gully pot design also will be a good choice in the future. However, the experiment results show that the new alternatives will cause a higher water level on the testing table. Also the bicycle safety on the road should be considered. For the further research, the experiment method should be improved and the maintenance cost for the new design should be a concern.
Research After literature study, it is clear that my research focuses on large particles clogging problem. To achieve my goal, the approach could be divided in several aspects: 1. In the first place, In order to define the large particles which real clogged gully pot, a field work to interview the on-site workers from cleaning company is done. 2. Based on feedback from on-site field work, 4 kind of new alternatives are proposed. 3. Then a laboratory experiment is designed to test these alternatives and also a new re-designed gully pot provided by Wavin Company.
Results 1. The new grating alternatives for original gully pot can significantly reduce the incidence of gully pot clogging problem. They can reduce the covering percentage of the grating during the extreme rain fall event and leave more opening space on the grating. 2. The new gully pot from Wavin Company has a better performance than the original gully pot. But considering the big settling tank and large grating of the new gully pot, it is not fair to directly compare with the other alternatives of original gully pot.
Student: Thesis Committee:
Q. Hao Prof.dr.ir. N.C. van de Giesen, Dr.ir.F.H.M. van de Ven, Prof.dr.ir. Wim S.J. Uijttewaal, Dr.ir. Marie-claire ten Veldhuis
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
78 | Master’s Theses November 2012
5
Watermanagement
Evaluation of hazard classification systems Of water source, sanitation and hygiene behavior in determining drinking water safety Introduction
Results
The research was performed in two rural sites in Thailand and Laos. The Diarrhea and Dengue (DIADEN) group from the Norwegian University of Life Sciences facilitated the fieldwork. In the Thai site, rainwater was the main drinking water source, whereas in Lao site, unprotected dug well was predominant in dry season and was replaced by rainwater in
1. The first investigation found that the hazards in Laos were more severe than in Thailand. 2. Water quality of the rainwater source (improved) was variably contaminated. The unprotected dug well (unimproved) was grossly contaminated. 3. Water quality at the household containers was also variable.
wet season. Drinking water was largely consumed untreated.
Overall, there was significant deterioration of water quality
Combined with varying sanitation service and hygiene behavior,
from sources to households that can be attributed to house-
it was assumed that the safety of drinking water might be
hold water handling practices (e.g. extraction methods,
compromised.
cleanliness, treatment). 4. The hazard classification system for water sources in Laos
Problem definition
was moderately correlated with water quality data and was
The global monitoring of the MDG target to halve the popula-
not significantly correlated for Thailand. The sanitation and
tion without safe drinking water access is performed by the
hygiene hazards were not significantly correlated in both
Joint Monitoring Programme (JMP). The JMP uses technological classification (improved or unimproved sources) as monitoring indicator for water safety. This has been criticized
sites. 5. The CBT data was significantly different from the Colisure/ Quanti-tray 2000 data.
for being inadequate in representing the actual conditions in water provision. The core argument is that drinking water quality at improved sources might not necessarily be free from pathogens. In addition, drinking water that is safe at the sources might as well be recontaminated through various water handling practices, particularly where manual collection, transport and storage are common. Thus, in this study it is proposed that the technological classification is refined through the use of a semi-quantitative hazard classification system.
Research In the first part, the research was focused on the identification and classification of the hazards found at the various water sources and the hazards related to sanitation facility and hygiene behavior. This was achieved through sanitary inspection, household questionnaire and spot observation carried out in about two weeks time. In the second part,
Household storage (medium earth jars) and point of use container (plastic gallon) in Laos (left) Rainwater collection systems (large concrete jars) in Thailand (right)
Conclusions and recommendations
water samples were collected twice at selected sources and
The JMP indicator overestimates water safety both at sources
household drinking containers. Samples were tested for E. coli
and at households. The hazard classification system, if refined
as faecal indicator organisms, using the standard Colisure/
further with weighted-scoring and long-term water quality
Ouanti-tray 2000 method from IDEXX. The water quality data
data, might enable a more accurate representation of the
were then used to validate the hazard classification systems.
actual conditions. Correlations with health impacts are also
Simultaneously, a new E. coli enumeration method, the
recommended. Furthermore, manual water handling practices
Compartment Bag Test (CBT) by University of North Carolina,
compromises water quality and it is thus advised to eliminate
was used in parallel to investigate the comparability of the two
hand-water contact as much as possible.
tests.
Student: Thesis Committee:
W. Novalia Prof.dr. G. Medema, Prof.dr.ir. J.B. van Lier, Dr.ir. M. Bakker, Prof. T. A. Stenström
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
79 | Master’s Theses November 2012
5
Watermanagement
Financial Sustainability of Rural Water Supplies in Western Kenya Comparing technology types and management models Introduction Kenya is in the top ten of countries with the largest population without access to safe drinking water. Large investments are done in the Kenyan rural water supply, but recent studies show that many of the new water supplies stop functioning within a few years after implementation. This study compares the financial sustainability of rural water supplies in Western Kenya. Within this comparison the aim is to compare different technology types, different management models and different combinations of these two. The included technology types are a handpump and a motorized pump, both used for ground water pumping. The included management models are community management, government management and private management. For 27 handpumps and 25 motorized pumps data are collected about service level, operation and maintenance, financial management and cost recovery.
Results / Conclusions • • Out of all handpumps, the locations with community management and the locations with combined community and government management scored low. The communities were not able to collect enough money. The private managed handpumps scored good, especially in terms of cost recovery and quick response to breakdowns. • • The motorized pumps scored low at the locations with combined community and government management and at the locations with government management. At the community managed motorized pumps, the committees were well organized but they did not manage to make all users pay. At the privately managed motorized pumps, the responsibilities for O&M and financial management were not clearly defined but the financial situation was good. • • Comparing the two technologies, the handpumps score higher on cost recovery and the motorized pumps score higher on O&M and financial management. The responsible entities at the motorized pumps have more need to be organized because of the daily need for staff and money for e.g. fuel refilling. A negative side of the motorized pumps are the high costs per user per year, about nine times higher
Student: Thesis Committee:
than at the handpumps. • • Comparing the four management models, the differences were not big. The community managed locations have difficulties with making people pay. At the combined managed systems the responsibilities for O&M and financial management are not clear. At the government systems the costs (including high salaries of government staff) are too high for the amount of users. The privately managed systems score slightly higher, especially in terms of cost recovery.
Recommendations Four recommendations are made: • • The higher costs make the motorized pump less suitable for use in rural areas of Western Kenya. • • Actions regarding users’ willingness to pay are required: economic development, training about the importance of clean water which is not for free and training for responsible entities about dealing with sanctions against non-payment and about making finances more transparent. • • Improving community management by increasing the influence of the local authorities: part of major maintenance costs, performance monitoring and retraining. • • More attention for private management including government contribution in investment costs, training for private owners and formal recognition of private management.
A. Adams Prof.ir. L.C. Rietveld, Dr.ir. D. van Halem, C. Tiwari, Dr. J.O. Kroesen
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
80 | Master’s Theses November 2012
5
Watermanagement
Water quality in bathing waters An analysis to determine the influencing factors on faecal bacteria concentration peaks Introduction
Results
The water quality at bathing locations in the Netherlands is assessed once every two weeks during the bathing season by monitoring for the presence of faecal indicator bacteria, Escherichia coli and intestinal enterococci. If the limits of bacteria concentrations (CEC, 76/160/EEG and CEU, 2006/7/EG) are exceeded the public is informed via the internet and by posting signs at the bathing locations.
Problem definition Swimmers who have a low immune system, like older people, children and sick people, are most vulnerable to the effects of faecal bacteria. Therefore it is important that the public is notified not to use the bathing water as soon as possible when the concentrations of faecal indicators are too high. Peaks of faecal indicator bacteria can occur rapidly, therefore the peaks are not always detected and a warning cannot be given in time to warn the bathers. This thesis helps to identify influencing factors for further use in future predictive modelling research in order to predict those peaks for small, fresh water, inland lakes.
Research In this thesis research was conducted into various variables representing meteorological conditions, physical characteristics and external pollution sources, at 52 fresh water bathing locations, which are thought to be of influence on the concentrations of the faecal indicator bacteria Escherichia coli and intestinal enterococci. The analysis was done by using Spearman’s correlation method to find a relationship between the continuous variables and the bacteria concentrations and Point-Biserial correlation to find relationships between the bacteria and dichotomous variables. The Mann-Whitney U-test and the Kruskal-Wallis test were performed to see if the difference in distribution between categories is statistically significant and thus indicating an influencing category.
Statistically significant relationships were found with E.coli and/or intestinal enterococci for the following variables: •• •• •• •• •• ••
surface area of the bathing water depth of the bathing water presence of an adjacent combined sewer overflow rainfall the average air temperature soil type
Conclusions and recommendations The variables average air temperature, soil type and rainfall are likely to have covariance to other variables and it is recommended to study that suspected covariance in future research. This thesis encountered several difficulties concerning data reliability due to estimates of the variables of several external pollution sources such as numbers of Swimmers and Boats and presence of Manuring. The analysis is thought to be unreliable and in the absence of actual daily data, the use of these variables for predictive modelling of peak contamination events will be limited. Therefore another recommendation is given for future reference to procure the necessary data from fieldwork or a reliable secondary source. The most pressing recommendation is to increase the temporal resolution of the water quality samples that are now taken biweekly. This frequency is not enough to detect the peaks in the concentration.
Student: I. Blommers Thesis Committee P rof.dr. G. Medema, Dr.ir. J.A.E. ten Veldhuis, Ir. R.W. Hut
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
81 | Master’s Theses November 2012
5
Watermanagement
Future Threats in drinking water winning from the Afgedamde Maas
Introduction
Results
Dunea yearly produces and supplies about 75 million m 3 drinking water to 1.2 million customers in the Western part of the Netherlands. The source of the drinking water production is surface water from the Afgedamde Maas, a branch of the river Meuse. The multi barrier treatment delivers an excellent drinking water quality that comply all strict guidelines of the Dutch Drinking Water Law.
Problem definition Dunea recognize future threats in form of polar organic micropollutants (OMPs). Pharmaceutically active compounds and pesticides are main contaminants detected structurally in the river Meuse and they are of concern to drinking water utilities because of their possible long term effects, the possibility of mixture activity and the sensitivity for customer perception.
Research Dunea built a pilot plant in the pre-treatment in Bergambacht to investigate Advanced Oxidation Processes (AOPs) to increase the barrier against OMPs. My research concerned applying AOP with O 3/H 2O 2, commonly called peroxone process, with the goals: 1. Investigation of the optimal dosage combination of hydrogen peroxide and ozone for the best conversion of OMPs, without exceeding the Company guideline for bromate 2. Investigation of catalysts to decompose excessive hydrogen peroxide
Student: Thesis Committee:
1. The bromate concentrations at setting 6/1.5 (6 mg/L hydrogen peroxide and 1.5 mg/L ozone) varied from 0.27 till 0.69 μg/L, with an average of 0.41 μg/L and complied the Company bromate guideline of an average value 0.5 μg/L and a maximum of 1 μg/L. With that optimal peroxone setting, the conversion of the 14 dosed target compounds differed between 24% and > 95%, with an average conversion of all compounds of 70%. The ozone dosage mainly determines the conversion and the peroxide limits the bromate formation. 2. Decomposing excessive hydrogen peroxide after applying peroxone in the pre-treated water, up to about 5.75 mg/L till 0.25 mg/L in the infiltrated water in the dune areas, required an EBCT of about 150 seconds with GAC. With ground water gravel skins, the required EBCT was spectacularly lower, no longer than about 11 seconds.
Conclusions and Recommendations It was proved that peroxone will increase the robustness of the multi barrier treatment of Dunea against OMPs. The bromate formation can be controlled and comply the strict Company guideline. Ground water gravel skin is a very promising catalyst to decompose excessive peroxide. Research to this catalyst, also suitable for up flow operation, is advised.
A.H. Knol Prof. Ir. J.C. van Dijk, Prof. dr. ir. T.N. Olsthoorn, Dr. ir. J.Q.J.C. Verberk, Ir. K. Lekkerkerker-Teunissen
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
82 | Master’s Theses November 2012
5
Watermanagement
Transition experiments in Amsterdam; Conceptual and empirical analysis of two transition experiments in the WATERgraafsmeer program The city of Amsterdam is faced with substantial challenges in maintaining urban living quality. Increasing societal involvement and inflexibility of the urban governance system have ceased progress in water management, ecological quality and sustainability. In the Watergraafsmeer area, a low-lying urban polder area in the eastern part of Amsterdam, these issues are perceived as persistent. Under the flag of the WATERgraafsmeer program transition management is adopted as a governance approach to change and water management is taken as the key carrier for sustainable development. In transition management, experimenting is a vital activity and transitions experiments are designed to assure their contribution to change. In this research, transition experiments in the Watergraafsmeer area are analyzed, using the mechanisms of deepening, broadening and scaling-up and their operationalization in 11 project characteristics. The research is based on an analysis of primary sources on the WATERgraafsmeer program. The case studies show that WATERgraafsmeer functions well as a transition experiment. They also show how the overall program and local project support each other in their quest for sustainable development. Furthermore we conclude that the management guidelines for transition experiments fail to accommodate interaction processes between project and program and lacks attention for substance.
Student: Thesis Committee:
N.I. Lugt Prof.dr.ir. N.C. van de Giesen, Dr.ir. F.H.M. van de Ven, Dr.ir. J.S. Timmermans, Drs. M. Claassen
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
83 | Master’s Theses November 2012
5
Watermanagement
Bonding and Bridging in Capacity Development Networks to address Wicked Water Challenges Capacity development has become an increasingly hot topic in the water sector. The development of individual, organizational, institutional and even societal capacities is argued to be required to be able to addressing the present-day water challenges. From a natural resources management context, much literature is available on WHAT is required for capacity development: social learning in social networks, by means of which an integrated view of the challenges under consideration could be established, effective participation is enabled, and a resilient adaptive water system should be developed. However, HOW to achieve this is a much less considered topic in water related contexts and forms the main topic of this thesis, which centers on the following central research question:
the water system and an adaptive water management approach. This thesis concludes that a careful balance is required between bonding and bridging on the network level, proximity and diversity on the relational level, and the ‘right’ personal characteristics on the individual level. It provides a scientific basis for practical insights and recommendation for capacity developers on how to design their capacity development projects.
Which social network characteristics, with a focus on bonding and bridging mechanisms, facilitate social learning in capacity development networks that aim to address wicked water challenges? Combing insights from the Science Communications field and other related fields of study regarding knowledge management, social network analysis and social capital provided a framework on the important roles of bonding and bridging mechanisms in social networks and their benefits for social learning for capacity development. Bonding mechanisms are closely related to similarities between network members (also called relational proximity), while bridging mechanisms are on the contrary characterized by diversity on the relational level. Paradoxically both mechanisms, and both proximity and diversity, turn out to have important benefits for capacity development to address water challenges, which are often considered to be ‘wicked’ due to the involvement of great systems complexity, stakeholders diversity and uncertainty. Bonding mechanisms in social networks benefit the knowledge sharing efficiency, quality and frequency, resulting in a high potential for effective stakeholder participation. Cross-boundary bridges within such capacity development networks facilitate social learning by introducing novel and nonredundant knowledge into the network, enabling the establishment of in integrated multidisciplinary view on
Student: Thesis Committee:
M.M. Pieron Prof.dr.ir. N.C. van de Giesen, Dr. M.C.A. Van der Sanden, Dr. E. Mostert, M. van der Zouwen, Drs. C. Wehrmann
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
84 | Master’s Theses November 2012
5
Watermanagement
Influence of wave climate schematisation on the simulated morphological development of the Western Scheldt entrance In the entrance of the estuary of the Western Scheldt (defined as the area between Vlissingen and Terneuzen), wave conditions are dominated by local wind conditions rather than by wave conditions at the North Sea. This is caused by the presence of the ebb tidal delta in front of the entrance. Waves influence the simulated morphology by eroding shoals edges, depositing sediment in the adjacent channels and by partly shifting patterns of erosion and sedimentation. Waves have the most influence at relative shallow areas where also tidal currents are present. These areas are in particular the shoals of Spijkerplaat and the shoals south of the Everingen flood channel. The way the wave climate is schematised influences the simulated local morphological development up to 20% to 25% (on the spatial scale of the channels and shoals and a time scale of one year). The amount of wind and wave classes within the climate schematisation has the most influence on the simulated morphology (up 20% to 25%). Other influences within the schematisation are subordinate to the influence of the amount of classes (in the order of 5%). Including a storm event within the wave climate schematisation, has limited influence on the considered time and spatial scale (order of 5%). On the time scale of one year, the influence of the storm is to a large extent redone by more occurring, moderate conditions. For the simulation of the morphological development in the entrance of the Western Scheldt it is recommended to apply a wave climate schematisation of five wind and wave classes at most. The schematisation should be based on the reproduction of the bottom changes in the estuary, seasonality and storm event don’t need to be taken into account.
Student: Thesis Committee:
B.W.F. van Rijn Prof.dr.ir. M.J.F. Stive
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
85 | Master’s Theses November 2012
5
Watermanagement
Evaluate two different PAC operations in combination with submerged ceramic MF membrane in surface water treatment Introduction Membrane technologies, regarded as a modern technology, are playing an increasingly significant role in drinking water treatment. However, membrane fouling is one of the most important factors limiting the performance of membrane process. Pre-treatment is the first step to control membrane fouling. And coagulation is considered as the most common pre-treatment. Otherwise, as powdered activated carbon (PAC) can reduce taste, odour, colour and other concerns caused by organic material, it is widely used in conjunction with membrane microfiltration.
3. The total DOC and UV254 removal of these two operations are similar to each other during the experiment.
Problem definition Most PAC application in water treatment is the PAC/ MF or UF systems, which usually dose the PAC before the membrane filtration and with a frequent backwash during the filtration time. Besides, the operation of PAC pre-coated on the membrane surface is also studied by many researchers. However, most of them focus on the short time filtration within about two hours. The performance of long time filtration without backwash in pre-coated PAC operation is still necessary to be researched.
Research
Conclusions and Recommendations Combined with various aspects of results, it is can be concluded that the PAC pre-coating operation in long time filtration has a better performance than that of continuous operation. But the research has to be continued to test and improve the PAC pre-coating approach.
My research focuses on the evaluate the PAC/MF system (continuous operation) and the PAC pre-coating operation on the membrane fouling in a long filtration time as well as on recovery, energy economization, NOM (DOC) and UV removal.
Results 1. Of the same flux, the recovery of TMP in PAC precoating channel after every cycle (6 hour)’s backwash was higher compared to continuous operation. The PAC pre-coating operation had a better performance on membrane fouling. And the most important fouling in continuous operation is the cake fouling, which is non-backwashable. Whereas, the most fouling in pre-coating can be backwashable. 2. The PAC pre-coating operation had a high recovery with 99.2% while the continuous operation owed a normal recovery of 85.5%.
Student: Thesis Committee:
C. Yun Prof.dr.ir. L.C. Rietveld, Dr. ir. B. Heijman, Dr.ir. H. Vrouwenvelder, P. Lu
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
86 | Master’s Theses November 2012
5
Watermanagement
Phosphorus removal by ceramic tight ultrafiltration (CTUF) membrane for RO pre-treatment
Introduction
Results
This MSc program is part of ICAN project (Innovative application of ceramic ultra- and nano- filtration). The project is aiming at wastewater reclamation and in ICAN, the RO system is chosen to treat the waste water thus effluent of RO system will be reused as industrial water for the factory. Due to large number of inorganic and organic matters of the feed water, bio-foiling will occur which needs to be controlled. Phosphorus limitation is one strategy to control bio-fouling. This report focuses on phosphorus removal by ceramic tight ultrafiltration (CTUF) membranes (1kD and 3kD MWCO) as a pretreatment before RO systems.
Problem definition 1. What could be the highest removal rate of phosphorus with CTUF membranes in different filtration conditions? 2. What are the influence factors of phosphorus removal and how do they influence the removal rate of phosphorus
Research The research in laboratory consists for more than six months. Here are planned phases to answer the research questions. 1. Observe removal rate of P-PO 4 with different fluxes, cross flow velocities, phosphorus concentrations in feed water 2. Observe removal rate of P-PO 4 with different solutions (NaCl & Na2SO4) 3. Observe removal rate of P-PO 4 with different pH value (5.7~9) 4. Zeta potential measurements
Student: Thesis Committee:
A. Increasing flux, cross flow velocity will increase the removal rate of phosphate. B. Increasing ions strength decreases the double layer thickness and decreases the removal rate of phosphate. C. The pH effect both the zeta potential of the membrane as well as the charge of the phosphate ion. Increasing pH will increase removal rate of phosphate but after pH 8.3, removal rate of phosphate begins to decrease. D. In the same ionic strength, the zeta potential of membrane with NaCl solution is larger than it with Na 2SO 4 solution and larger zeta potential gets better removal rate of phosphorus.
Conclusions and recommendations CTUF membrane could remove phosphorus and its removal rate is determined by operational parameters. Larger flux and cross flow velocity will have better removal rates and at pH 8.3 the removal rate gets highest. The following steps are suggested that observing phosphorus removal rates with NOM in feed water, with effluent of wastewater plant as feed water and combine coagulation.
Z. Zeng Prof.dr.ir. L.C. Rietveld, Dr.ir. B. Heijman, Ir. R.Shang, Dr.ir. H.Vrouwenvelder
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
87 | Master’s Theses November 2012
5
Watermanagement
Farmers’ Strategies Coping with Water Shortage; A Case Study in the Irrigation District of La Joya Antigua, Peru
The irrigation district of La Joya Antigua (Province and Department of Arequipa, Peru), is located in the Chili-Quilca river basin, which lies between the Andes Mountains and the southwestern coastline of Peru. The location of this irrigation district leads to a limited amount of annual precipitation and the loamy sand type soil of the district; together with the gravity irrigation system, the low irrigation efficiency, the sensitivity of the regulated discharges from the upstream reservoirs, the irrigation district of La Joya Antigua encounters scarcity of irrigation water specially during dry years. According to the history of the district, irrigation activities have been performed in the irrigation district of La Joya Antigua since 1939. In order to cope with water shortages, certain strategies must have been taken by the local farmers. This has led to the research questions of this study: What strategies do farmers take to cope with water shortage in the irrigation district of La Joya Antigua? Do these strategies help to relieve water shortage? Furthermore, in order to compare with the farmers’ strategies, crop water demands under deficit irrigation are modeled to see whether the application of deficit irrigation can bring a better crop performance during water shortage. In order to answer the above research questions, a fieldwork was performed in the irrigation district of La Joya Antigua. During the fieldwork, the discharge and dimension measurements of the selected irrigation canals were done and the interviews were given to the local farmers and authorities. With all the data from the fieldwork, a SOBEK model was built to simulate the irrigation water availability and an AquaCrop model was built to simulate the crop water demand in the irrigation district of La Joya Antigua.
Student: Thesis Committee:
The results of the study show that there is sufficient irrigation water on most of the farms in a wet year but deficit of irrigation water in a dry year. Furthermore, the study shows that the percentage of prickly pear cactus planted on each farm has a strong connection with the irrigation water availability of the farm. The cultivation of the prickly pear cactus has contributed to the reduction of crop water demand of the midstream and downstream farms, which ensures a sufficient irrigation water supply on most of the farms in the irrigation district of La Joya Antigua in a wet year. However, in a dry year, the amount of irrigation water supplied to the farms are too low to meet the crop water demand of the farms. Under the dry year situation, strategies are taken by the local farmers to reduce the yield losses of the crops on their farms. The most common strategies that are taken by the farmers are: focusing on irrigating certain crops while giving up others, reducing the irrigation area, and changing crops to less water demand crops. Study shows that the farmers’ strategies, although mainly based on experience, have potential to reduce the crop water demand in a large extent. On most of the farms, the farmers’ strategies bring a balance between the crop water demand and the irrigation water supply under water shortage; While deficit irrigation only reduces very little crop water demand and cannot bring a balance between the crop water demand and the irrigation water supply. From the study it can be seen that the farmers’ strategies have contributed to the development and continuous irrigation activities in the irrigation district of La Joya Antigua for more than 70 years. Suggestions are proposed to the local authorities and farmers to be aware of the impacts of the monoculture. Besides, it is suggested that the local authorities provide financial support and technical support to the farmers who would like to change their irrigation method. From the farmers’ point of view, it is suggested that the local authorities put attention on solving the water-related conflicts between farm neighbours and enforce their power to the rule offenders; the treatment of irrigation water is appealed by the local farmers and should also be considered by the local authorities.
B. Zhang Prof.dr.ir. N.C. van de Giesen, Dr.ir. M.W. Ertsen, Dr.ir. J.S. Timmermans, Ir. C. Machicao Pereyra
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
88 | Master’s Theses November 2012
5
Watermanagement
Struvite Crystallization and Separation in Digested Sludge
Phosphorus depletion is an emerging and serious global environmental issue. At this moment, research and policy discussion on phosphorus scarcity is still limited. This research investigates the possibilities of phosphorus recovery by controlled precipitation of struvite from digested sludge. At Waternet’s wastewater treatment plant Amsterdam West, plans for a struvite reactor are scheduled. The advantage of phosphorous recovery through struvite precipitation from digested sludge is three-fold. First, struvite can be directly used as fertilizer. Second, undesirable struvite precipitation in the wastewater treatment plant is prevented by reducing the phosphorus concentration in the dewatering reject stream which is fed back to the inlet of the treatment plant. Third, sludge dewaterability improves due to the addition of MgCl2. This thesis investigates the influence of mixing speed, aeration rate, magnesium dosing method and crystal recycle method on struvite growth and phosphorus removal, as well as separation of struvite from sludge. For that purpose, experiments have been performed in a crystallization reactor and a counter-current washing column at lab scale at wastewater treatment plant Amsterdam West. MgCl2 was added under varying reactor conditions, struvite constituent concentrations were measured and struvite growth was assessed. First, it is demonstrated that struvite recovery is well possible in a stirred sludge environment at neutral pH commonly applied in sludge digesters (7.0 - 7.1). Phosphorous removal under these circumstances is at least 85%. More complete mixing by stirring at a higher speed further improves struvite recovery by keeping supersaturation low. Secondly, a significant difference in struvite recovery was observed between experiments in which MgCl2 is dosed instantly versus experiments in which MgCl2 is dosed gradually. Gradual MgCl2 dosage, and therefore rapid mixing, improves recovery compared to instant dosage. Mixing at a higher stirring speed further improves recovery. Thirdly, it is found that struvite recovery under given circumstances is poor in a combined aerated and stirred sludge environment. In such environment higher aeration rates deteriorate struvite recovery further, while struvite recovery improves with decreasing aeration rates at a higher stirring speed. Fourthly, struvite sepa-
Student: Thesis Committee:
ration experiments have verified that separation is well possible in a counter-current washing set-up, separating 86% of detectable struvite within 15 minutes at an upflow velocity of 1.3 mm/s.
W.J. de Buck Prof.dr.ir. J.B. Van Lier, Prof.dr.ir. L.C. Rietveld
For further information please contact the section Water Management, +31 (0)15 278 1646 Email:
[email protected]
89 | Master’s Theses November 2012
5
Watermanagement
90 | Master’s Theses November 2012
5. Civil Engineering theses
Transport & Planning
5
Transport & Planning
Measuring the influence of congested bottlenecks on the route choice behavior of pedestrians at Utrecht Centraal To make sure busy railway stations can cope with increasing pedestrian flows, there exists a need for more knowledge about pedestrian behavior among NS Stations. The goal of the present research is to design and apply a methodology to use measurement equipment for a combination of congestion and route choice measurement at railway station Utrecht Centraal. As techniques used for measurement are relatively new to pedestrian research, a lot of attention is given to validation and calibration.
It is shown that it is in particular important to design the Bluetooth system in such a way that walking direction and route alternatives are clearly distinguishable. Bluetooth data can be used to find route choice differences for groups of pedestrians. The combination with CCTV data currently seems to be the only way to find a relation between congestion and route choice. Without such CCTV data, the determination of a data aggregation method seems to be the most important problem to solve.
Measurement equipment consists of a photo based “Customer & Crowd Behavior Analyzer”, or CCB in short, and a Bluetooth based route measurement system. CCB is designed to estimate local traffic states by measuring flow, while Bluetooth is used to detect pedestrians at multiple locations to derive routes. The combination of these data leads to route flow distributions through the station.
Analysis of origin-destination relations shows that the presence of the escalator significantly influences route choice at the stairway bottleneck. It is furthermore shown that approximately 15% of pedestrians choose their routes differently during congestion periods. Issues that explain this difference may be time related, such as congestion, habit, or travel purpose. To assess the influence of congestion, a choice model is estimated, relating waiting time measurement to route flow measurement. This model predicts that 10% to 50% of pedestrians change their route choice, depending on the severity of congestion. To estimate a relation between walking time and route choice, data are aggregated per arriving train. It is expected that a different aggregation level may yield better results, but this would require collection of more accurate train arrival time data.
The station hall at Utrecht Centraal is a location with very high densities and flows during peak hours. When trains arrive, the formation of queues at the escalators is common practice at platforms. In its current state of reconstruction, the station offers the unique opportunity to observe pedestrian traffic in (near) congested state. The main research question is: How to measure the influence of congested bottlenecks on route choice of pedestrians, and what is this influence at Utrecht Centraal? A method is developed to measure route choice behavior from a combination of CCB and Bluetooth data. The conclusions on validity of CCB and Bluetooth are used to find a practical approach. As the CCB technology in its current state requires manual observation, a CCTV video system is included in the approach. A combination of data sources enables measurement of route flows, walking times and congestion. A measurement area with a total of four alternative platform access points is chosen, including an escalator and a stairway bottleneck.
Student: Thesis Committee
This research shows that pedestrians change their route choice when congestion occurs. Data suggest that part of the population has a habit to avoid bottleneck routes even when no congestion is present. This effect is probably caused by the large number of daily commuters. It is expected that station travellers in general will adapt their route choice behavior to daily congestion situations. Analysis shows that the number of pedestrians avoiding a bottleneck increases when congestion occurs. This influence was established for both an escalator and a stairway bottleneck. The thesis is concluded with recommendations for further research, measurement application and design of railway stations.
H.A.W. Voskamp Prof.dr.ir. S.P. Hoogendoorn, Dr.ir. W. Daamen, Dr.ir. B.G.H. Gorte, Ir. P.B.L. Wiggenraad, Drs.ir. J. van den Heuvel MBA
For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
92 | Master’s Theses November 2012
5
Transport & Planning
A Framework for the Modelling and Ex-ante Evaluation of Coordinated Network Management
Since the second half of last century, traffic congestion on road network has become a predominant phenomenon due to the rapid increases in transport demand and number of vehicles. It starts to become clear until later that century traffic congestion cannot be solved single-handedly by expansions of road network. During peak hours, besides recurrent congestion caused by insatiable demand, non-recurrent congestion caused by incidents, adverse weather conditions and work zones, are becoming more problematic with their temporary disturbances causing traffic breakdowns. Developments and deployments of traffic control strategies come into effect to solve recurrent and non-recurrent congestions with a synthesis combining technologies, traffic theories, mathematics and kinematics. Although ITS control measures are relatively new, they transform into the backbones of a prevailing type of traffic management, Dynamic Traffic Management. When coordination and integration between DTM control measures is introduced as the advanced approach to restore the utilization of road network, great hope is placed on Coordinated Network Management to improve the effectiveness of traffic management.
Student: Thesis Committee:
The Field Test Integrated Traffic Management Amsterdam aims at investigating the effect and the control concept of coordinated network wide traffic management for the implementation in 2013. The graduation project is to develop an assessment methodology framework for modelling and ex-ante evaluation of CNM. This methodology is applied to the kidney shaped network of southern Amsterdam region in order to perform ex-ante evaluation on realizing and testing dynamic coordinated network management. Evaluations and validations of the above modelling are presented to show the effect of individual DTM and coordinated DTM, also known as CNM, under recurrent and non-recurrent congestions. A test solution towards advanced deployment strategies and methodologies based on an incident-induced empirical case is contrived later using Matlab. Simulation results are also presented in order to assess this test solution and the effect of CNM under its coordination strategies and methodologies. Finally, findings, conclusions, recommendations and future directions are drawn to bring the thesis project to completion. Hopefully, this thesis work could be referred to for the future implementation of CNM in the PPA project and it could be informative to other CNM related researches.
X. Zhang Prof.dr.ir. S. Hoogendoorn, Dr.ir. H. van Lint, Ir. P.B.L. Wiggenraad, Dr. V. Knoop, Dr.ir. H. Taale, Dr. S. Hoogendoorn-Lanser
For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
93 | Master’s Theses November 2012
5
Transport & Planning
An Assessment Framework for the Speed Policy on Dutch Motorways
Today the Dutch cabinet provides in implementing a maximum speed limit of 130 km/h on Dutch motorways as much as possible. As a consequence, research is needed to the circumstances where and when higher speed limits (or maybe a dynamic speed limit) will be acceptable. In other words, what speed limit is the most optimal for a road section taking the traffic flow, the environmental targets and the safety issues into mind?
After finishing the research, it can be concluded in general that the road authority desires lower speed limits than currently applied and that the road user desires higher speed limits, but it is the question whether or not 130 km/h is the optimal speed limit for the road user.
In order to do the research, an assessment framework for a new speed policy is developed. With an assessment framework, the speed limit on a road section can be assessed. A more optimal speed limit can be determined, either permanent or dynamic for that road section.
Student: Thesis Committee:
J. Kuijvenhoven Prof.dr.ir. S.P. Hoogendoorn, Dipl.-Inform. T. Schreiter, Dr.ir. H. Taale, Ir. M. Ludeking, Dr. J.A. Annema, Ir. P.B.L. Wiggenraad
For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
94 | Master’s Theses November 2012
5
Transport & Planning
Development of a prediction model for speed limit violations on tangent roadsections.
Speeding and red light running are among the major causes for road crashes. Respectively, speeding is more crucial for rural areas, whereas red light running is more frequent in urban areas where most of the traffic lights are located. To adequately address both issues consistent actions are needed in three main directions (also known as the three Es): engineering, education and enforcement. This study treated, in a way, the engineering and the enforcement. On the one hand, it reviewed the effect of road design and road side environment on speed and red light running that was reported in previous studies. On the other hand, the study aims at developing a model for prediction of the percentage of offenders depending on several road characteristics. It was found that age and gender is an important factor for both types of violations. The road characteristics reported to have an influence on speed are among others curve radius, curvature change rate, road, lane and shoulder width, shoulder type, type of objects and lateral distance, traffic signs and road marking, access points density and street lighting. In regard to red light running the most important factors are related to traffic signal characteristics (control type, cycle length, yellow interval duration), intersection characteristics (traffic volumes, grade, width, speed limit, number and width of approach lanes) and traffic flow characteristics (percentage of trucks).
Student: Thesis Committee:
The prediction model was based on speed and road data for the N roads in the Province of Gelderland in the Netherlands. The study was aimed at tangent sections and considered both driving directions together. When calculating the percentage of offenders a speed of 87 km/h was used as a limit. It was found that the percentage of offenders is considerably lower in horizontal curves than on tangent sections. Additionally, it was found that the horizontal curve effect disappears about 100 m from the beginning or end of the curve. After reduction, 64 sites were used for model calibration and 12 sites for validation of the resulted model coefficients. A linear and a nonlinear model were developed. Tangent length, median width and the presence of barriers were found to have a positive effect on the percentage of offenders. The presence of street lighting, on the other hand, had a negative correlation to the percentage of offenders. In the end, the only difference between both models was the logarithmic transformation of the tangent length. This transformation was necessary to capture the effect of relatively shorter tangents. This also explains the higher R2 for the nonlinear model. The R2 for the linear model is 0.428 and for the nonlinear model it is 0.502. Both models were equally well validated with the different sample of road sections. It was found that both models perform better for percentages of offenders between 15% and 45%.
M. Zamanov Prof.ir. F.C.M. Wegman, Dr. J.A. Annema, P. Wijers, A. Dijkstra, Ir. P.B.L. Wiggenraad
For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
95 | Master’s Theses November 2012
5
Transport & Planning
Realised capacity estimation with use of vertical queuing method Improving the method of estimating the overall effect of traffic measures on the vehicle delay time at the Dutch national freeway network Introduction The topic at which this thesis is based on is the effect of traffic measures at the vehicle delay time, VDT. The research focused towards the capacity effect of traffic measures. The effectiveness of traffic management measures is determined by their effect on the VDT. However, the development of the VDT is not singular influenced by the installation of measures. The challenge within the main topic is to unravel the total change of VDT into the contributions of all influencing factors. Within this thesis, the vertical queuing model is used to estimate the realised capacity, i.e. the actual achieved throughput during a congestion period under the prevailing conditions. Regression analysis estimates the contribution of the different individual influencing factors, such as traffic management measures, on the realised capacity.
Method The vertical queuing model uses the principle of first-infirst-out. Road sections are individually examined. The model is based on the count of the number of arriving and departing vehicles during the day. It is assumed that the total daily demand is served, i.e. eventually all traffic will pass the road section. All vehicles can pass without any delay as long as the demand does not exceed the capacity. A queue will build up in the model as soon as the demand does exceed the capacity.
Student: Thesis Committee:
The arrivals are determined by the demand and can be deduced from the traffic flow. The departures are restricted by the number of arrivals or by the capacity. While the VDT is measured, the queue length and therefore the difference between the cumulative arrivals and departures can be calculated. The total number of departures and arrivals before the beginning of a congestion period as well as directly after the congestion period are based on the measured traffic flows. The estimated realised capacity is the average traffic flow during the congestion period. The estimated realised capacity should be explained by the prevailing conditions. Regression analysis based on many records can estimate the effects of all the influencing factors. So in essence, the capacity is the variable in the model that is estimated based on the measured VDT and the measured cumulative traffic volumes. The regression analysis estimates effects and these effects can be transferred to effects on the VDT.
Conclusions The main conclusion is that it is possible to implement the vertical queuing model and to estimate effects of influencing factors on the capacity. The calculation of the effect on VDT is also possible, only there is need for further research to improve the estimation of the effect of prevented congestion periods. There now is a direct relation between measured traffic data and the effect of traffic management measures. It is also possible to unravel the effects of other factors such as adverse weather conditions.
M.J. Veenstra Prof.dr.ir. S.P. Hoogendoorn, Prof.dr. H.J. Meurs, Dr.ir. H. Taale, Ir. P.B.L. Wiggenraad
For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
96 | Master’s Theses November 2012
5
Transport & Planning
Quality assessment of an urban traffic network Recently the importance of traffic management has increased. Expansion of the traffic network is expensive, so the emphasis is on ‘better’ usage of the network.
The city of Rotterdam is also looking for a tactical framework on an urban scale. A tactical framework gives you an insight on where and when traffic problems occur. Besides this, current evaluation of traffic regulation-scenario’s mainly depends on accessibility of the traffic network.
Goal and research questions The goal of this research is to make a tactical framework for an urban traffic network and to look at possible weighting methods for the evaluation of traffic regulation-scenario’s. To reach this goal three research questions have been established: 1. How is a tactical framework for an urban traffic network designed? To answer this question the city of Rotterdam will be used as a case study to apply the GGB+ (Gebiedsgericht Benutten Plus) method. 2. How can the quality of the traffic network be defined? Before a widely supported evaluation can be given, first the objects on which the network will be evaluated have to be determined. These will be representative for the accessibility, safety and liveability. The quality of the traffic network will be defined according to the urban tactical framework. Next three different weighting methods between the objects will be investigated, so a widely supported evaluation can be given for an urban traffic network with the Kwaliteit Indicator Rotterdam (=Quality Indicator Rotterdam). 1. What is the current performance of the urban traffic network of the city Rotterdam, given the cities own objectives? Now the different weighting methods will be used in practice to see how the methods work in reality. Next to this the quality of the traffic network of Rotterdam can be given.
Student: Thesis Committee:
Conclusions The current GGB+ method is a good start for an urban tactical framework. With a few adjustments it’s very suitable for an urban area. With the new adjustments a better insight is given into other modalities in the network and their conflicts with the traffic. The three different weighting methods all have different approaches. The equality method gives a very objective quality evaluation. The utility method uses the affected people, so the biggest group has the biggest influence on the total quality. The air quality and safety are big in this equation. Final the monetarization method focuses more on the different modalities. The air quality and safety are close to zero, so they don’t have a significant effect on the total quality. The total urban area of Rotterdam was too big for a quality evaluation. Even though a lot of data is available of the traffic network of Rotterdam, at some points and times the data was invalid or missing.
Recommendations The datasets for the KIR are not sufficient yet. The waiting times of the public transport and the bicyclists and pedestrians are very poor. The use of the GGB+ method for the urban area isn’t explored completely. The method consists on ten steps, here only five are used to make an urban tactical framework. To make a complete unban approach of the GGB+, the complete method should be evaluated. Finally the weighting methods could use some fine-tuning. The utility method is depending on a lot of standard numbers. A better insight in these groups can change the weighting factors.
T. Blanken Prof.dr.ir. S. Hoogendoorn, Dr.ir. H. Taale, Ir. P.B.L. Wiggenraad, Dr.ir. J.H. Baggen, Ing. R. Gilbers
For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
97 | Master’s Theses November 2012
5
Transport & Planning
The Effect of Network Structure and Signal Settings on the Macroscopic Fundamental Diagram
Introduction
Method
Recently it has been proposed that the performance of a
To assess the effect of the structure on the network, a tool has
complete network can be represented graphically using only
been developed to automatically generate fictitious networks
aggregated data for flow and density. The resulting graph is
with different structures, in which the amount of infrastructure
the macroscopic fundamental diagram (MFD), which relates
and signal timings are matched dynamically to a randomly
the average flow (performance) to the number of vehicles
generated OD-matrix. The resulting networks are used as a
in the network (accumulation). The resulting shape is often
base for the simulations, which are done in the microscopic
concave, meaning that the performance can be maximised if a
traffic simulator VISSIM.
fixed number of vehicles is maintained in the network (optimal
Using various signal timings for signals located on the
accumulation). One of the most promising methods to achieve
perimeter, the flow from the subnetwork to the perimeter is
this, is by adapting signal timings.
restricted and vice-versa, in order to assess how the MFD of
characteristics of the roads (length, speed, capacity) and the
both react to these changes.
amount and type of intersections in the underlying network. The different factors influencing the shape of the MFD could
Conclusions
not be quantified – in order to construct MFDs based only on
Regarding the relation between the shape of the MFD and
knowledge of the network and without the use of simulations
the network structure, it is concluded that the structure of a
- as the shape of the MFD is found to differ strongly, even for
network in itself does not have a strong influence on the shape
similar networks. As such it is concluded that the stochastic and
of the MFD. Differences between MFDs are not caused by topo-
dynamic nature of traffic has a strong influence on the shape
logical differences, but by the different
of the MFD. Especially the accumulation is highly sensitive
Regarding the effect of signal settings on the shape of the
to differences in the distribution of traffic over the network,
MFD of a subnetwork and its perimeter and its applicability
making the optimal accumulation particularly hard to predict.
for control strategies, it is concluded that a strong relation between the MFD of the subnetwork and its perimeter does
Objective
exist, in which both react in the same way to changes in traffic
The objective of this thesis is to investigate if (1) a relationship
demand and signal timings. The ratio between the perfor-
between the shape of the MFD and the structure of the under-
mance of the subnetwork and perimeter is highly consistent
lying network exists and on which factors this depends and
and not strongly affected by changes in the signal settings,
(2) if the shape of the MFD of a subnetwork (neighbourhood)
implying that signal timings exist, which optimise the perfor-
and its perimeter (ring of higher level roads (with signalised
mance of both the subnetwork and its perimeter.
intersections) around a subnetwork) are affected by different
The optimal accumulation of the perimeter is found to be
signal timings and how this does affect the applicability of the
highly sensitive to changes in the signal timings. As acon-
MFD for control strategies.
sequence it is concluded that the MFD is difficult to usefor control strategies aiming to adapt signal timings to maintain the optimal accumulation in a part of the network, because these changed signal timings result in a different optimal accumulation.
MFD Controlled inflow: Network 3, Subnetwork 1 - Subnetwork perimeter
Student: D. de Jong Thesis Committee: Prof.dr.ir S.P. Hoogendoorn, Dr. V.L. Knoop, Dr.ir. J.W.C. van Lint, Dr.ir. H.Taale, Ir. P.B.L. Wiggenraad, Ir. M. Schreuder, Ir. A. Reijneveld For further information please contact the section Transport & Planning, 015 2789341 Email:
[email protected]
98 | Master’s Theses November 2012
6. Civil Engineering theses
Construction Management Engineering
6
Construction Management Engineering
Combining Early Contractor Involvement and Availability-Based Contracting in Complex Infrastructure Projects In order to terminate the malicious tradition of time and budget overruns, the construction industry is forced by new national policy to significantly improve performance. Early private participation and integrated contracts including co-financing seem to be effective methods to increase ‘Value for Money’ in infrastructure projects. Two approaches are investigated: AvailabilityBased Contracting (ABC) in the form of DBFM contracts and Early Contractor Involvement (ECI) interpreted as Interweaving Models 1&2. Their added value is shown separately in projects like A12 Lunetten-Veenendaal and A2 Maastricht, but no simultaneous application has been executed in the Netherlands yet. This might be a missed opportunity to increase value, therefore this research elaborates on the implications of combining ABC and ECI, in order to realise a successful combination in complex infrastructure projects.
All these directions are able to parry difficulties and to realise advantages. They are composed into a model that can serve as a plan of approach for future projects: The P4 Model for Project Planning. Therefore, it is recommended for the public client to identify whether a new project is suitable for the combination of ABC and ECI. Subsequently the developed model can be used as a guideline to actually realise added value in practice.
Opportunities to realise added value with the combination are found in the cumulation of advantages of the separate approaches, namely innovation, acceleration of procedures, lifecycle optimisation, high availability and realisation of the project within time and budget. But difficulties have to be faced as well, these can be expected in institutional, legal and financial issues. This is an indication that ABC and ECI cannot easily be combined in projects. Therefore it can be stated that simultaneous application does not unconditionally delivers added value. In order to do realise a successful combination, strategic preconditions and directions for solutions are developed. The identified preconditions are institutional consensus, a certain complexity and both a capable client and market. Only in case all these preconditions are met in projects, a window of opportunity for the combination of ECI and ABC occurs. Four main solutions are developed to enable the combination: Maximizing Planning Solution Space Postponed Funding Stepwise Procurement Provisions for Risk Settlements
Student: Thesis Committee:
A. Beekers Prof.dr.ir. A. Verbraeck, Mr. Fred Hobma, Drs. M. Leijten. P. de Wit, P. Brinkman
For further information please contact the section Construction Management Engineering, 015 2784774 Email:
[email protected]
100 | Master’s Theses November 2012
6
Construction Management Engineering
Assessing the Benefits of Construction Site Data Management
The AEC industry suffers from chronic problems of low produc-
using Vela. The difference between the two total estimates of
tivity and waste in terms of labor and materials. Furthermore,
weekly hours was the average weekly time savings, from which
non-conformance of built products results in the need for
efficiency gains could be calculated. This metric could be used
costly rework. These problems are well documented and are
to compare the average benefits achieved by using Vela, and
a major source of cost overruns and delays on construction
allowed a comparison of average results between projects. I
projects. However, a new generation of software tools has been
also hypothesized that a number of independent factors could
remedying the causes of waste and inefficiency in construc-
have an influence on these efficiency gains. These factors
tion by leveraging the benefits of building information models,
included: learning over time and level of familiarity with the
mobile tablet devices and cloud computing. These applica-
tools, amount of subcontractor, owner, designer or inspector
tions are referred to as field data management tools (FDMT)
involvement with Vela, number of functionality tools used and
within the industry. These tools allow construction managers to
stage of project in which Vela was introduced.
accurately record, communicate and track crucial information
The study found that a total of 38 surveyed users saved on
on the construction site. The collection of reliable production
average 9,1 hours a week using Vela, resulting in an average
data and tracking of project progress are key parts of lean
efficiency gain of 16% while conducting typical construc-
manufacturing and has been commonplace in other industries
tion management tasks. These average efficiency gains vary
for decades. This process of managing field data is primarily
substantially between users and projects, due to a number
being used to track construction quality issues. QA/QC
of influencing factors. The most important factor influencing
checklists can be accessed on iPads, and any non-affirmative
efficiency gains identified by the quantitative research was
response prompts the automatic creation of an issue, which
the involvement of non-Skanska project participants with Vela,
is added to a commonly accessible database, from where it
namely subcontractors, clients and commissioning agents.
can be accessed and updated as needed. Thanks to barcodes,
Another significant finding was that Vela administrators who
QR codes and RFID tags, it is also possible to automatically
are also designated Vela trainers within Skanska are involved
identify building materials and equipment, allowing construc-
with projects whose Vela users recorded a higher average effi-
tion teams to track components from procurement through to
ciency gain, suggesting that the depth of knowledge of how to
eventual installation and commissioning on site. The resulting
use an FDMT is an important factor influencing efficiency gains.
accuracy and schedule improvements allow optimization of
By focusing on increasing the depth of administrator knowledge
on-site inventories and facilitate the use of prefabricated or
and the involvement of subcontractors, owners and commis-
modular components.
sioning agents with FDMTs, construction service providers should be able to incrementally increase the efficiency gains
Until now there has never been a comprehensive study to iden-
which they achieve through using FDMTs. The techniques used
tify what factors influence the effectiveness of using FDMTs.
to measure efficiency gains fit into a fuller ROI assessment
I carried out a study on 15 individual projects being under-
framework for FDMTs to include quantitative measurements of
taken by Skanska building USA, which were using an applica-
quality improvements as well as costs when assessing innova-
tion called Vela (now Autodesk BIM 360 Field) to manage
tive construction approaches. At best, the proper management
different types of field data. The primary goal of the research
of field data can be a comprehensive method for coordinating
was to determine which factors within a project influence the
supply chain management, construction activities and building
efficiency gains achieved through using FDMTs, and identify
maintenance post-completion. In addition to incremental
best practices which could enable projects and construc-
efficiency improvements, a thoughtful consideration of the full
tion management firms to improve their field data manage-
potential use of FDMTs can help construction service providers
ment approach. After interviews with Skanska construction
such as Skanska fundamentally increase the efficiency of
managers, I divided weekly activities into 17 typical tasks,
their operations business processes and give them a distinct
and surveyed users of Vela on each project, asking them to
competitive advantage with clients.
estimate the average hours they devoted to each task before using Vela, and the average hours spent on each task while
Student: Thesis Committee:
M.S. Moran Prof.dr.ir H.A.J. De Ridder, Dr.ir. G.A. Sander van Neederveen, Dr.ir. A. Koutamanis.
For further information please contact the section Construction Management Engineering, 015 2784774 Email:
[email protected]
101 | Master’s Theses November 2012
6
Construction Management Engineering
Applying the Supply-driven integrated design approach Put into practice upon a Modular Façade company During the past few years, academics of Building and Construction have raised awareness of the inadequacies on the way the industry is being conducted. Complaints about delays, over-budgets, low quality, little variation, and actors relationships heading into to legal battles are of common knowledge among practitioners. Problems have been recognized to have a frequent origin, the supply-chain. Construction projects usually do not belong to the realm of repetitive making, and every construction project has to deal with a fragmented chain of work, products and information, resulting in reactive producers, lack of innovation, and little standardization on elements. Fortunately, proposals to change this industry recipe are being developed and tested in a few projects, fueled by the requirements of the market that claim an improved service. This graduation work focuses on changing old fashion, and inefficient manners, in favor of an alternative concept to do integrated design and delivery of BC works, by assuming a more dominant role of the supplier in the design process. This concept is called Supply-Driven Integrated design approach.
Implementation of this approach was pursued for a Dutch construction company, ALDOWA B.V. In order to implement such approach two conditions were established: First, the concept demands a supplier’s building system (an entity enclosing a Modular Building block, and universal parametric rules that control the block). Second, the concept needs an enabling tool that guides the clients through the supplier’s building system, illustrating constraints and possible solutions. With this enabling tool, a virtual market where the client can configure and select a building product (derived from Modular Building Blocks) is effectively set-up, triggering a paradigm shift for the company, and its clients. The work elucidates all the steps, processes, requirements and demonstrations of the enabling tool to create the first time a link between scientific knowledge and business implementation in a real company. The tools developed to implement the supply driven design approach are also expected to help reduce the effort spent by ALDOWA B.V. in the tendering procedures and design and configuration procedures, leading to a more efficient and competent operation of the company.
The approach advocates for a revolutionary idea: to make construction industry market more alike to other’s industries markets, such as automotive or aerospace market, where the clients have to select or configure a modifiable product according to their needs, instead of expressing their needs to have a product manufactures exclusively for them. This change of roles has positive impacts on many aspects of the supply-chain, because encourages producers to specialize and develop a push market with their own products and brands, resulting in expertise and efficiency in the final product, promoting innovation, and lowering time of production and the prices for the client.
Student: Thesis Committee:
M.A. Moreno Sanchez Prof.dr.ir. H.A.J. de Ridder, Dr.ir. G.A. van Nederveen, Ir. H.R. Schipper, Allard Droste
For further information please contact the section Construction Management Engineering, 015 2784774 Email:
[email protected]
102 | Master’s Theses November 2012
7. Last year’s Civil Engineering Theses
7
Last year’s Theses
Master’s Theses June 2012
Civil Engineering theses Building Engineering
Tunnel induced settlement damage: A case study to improve damage prediction for façades Student: L.A.J. van Kessel
A user-centred re-design of indoor comfort Student: B.C.M. van Agtmaal
Fire safety design of a high-rise timber building Student: G. Longhi
Reusing Knowledge at Van Rossum BV Student: J. van Ballegooij
In-situ fire spalling testing applying a mobile furnace 29 Student: B.I.E. Pieters
Investigation of damping in high-rise buildings Student: R.L.J. van den Berg
Experimental and Numerical Characterization of Membrane Adhesive Bonding Strength on Orthotropic Steel Deck Bridges Student: Y. Yang
Tensile-compression ring; a study for football stadia roof structures Student: I. Boom Heat flux roofs Student: F.L. Gunnink
Frost Salt Scaling of Blast Furnace Slag concrete Student: S. Leurs Segment-joint capacity of the Kiltunnel Student: I. Schols
Stapelen met houtskeletbouw Student: T. Hoekstra
Hydraulic Engineering
Building Envelope Refurbishment of Multi-residential Postwar Buildings – Investigation via a case study Student: A. Loukopoulou A building method for precast concrete high-rise buildings Student: M.L. van der Meij
Process-based modelling of the Maumusson inlet (France) Student: E.W.J. Bergsma Bow Thruster Currents at Open Quay Constructions on Piles Student: R. van Doorn Nourishing intertidal foreshore: Improving safety and nature Student: L. de Graaf
Structural Engineering Optimisation of a high strength concrete plate bridge Student: T.J.P.M. de Goede Evaluation of the structural pavement condition by means of longitudinal profile data Student: J.A. Alleman 2D Numerical Analysis of Settlement Damage to Buildings: Student: B.W.P. Albers Crack width in reinforced steel fibre concrete Student: R. Cederhout Effect of TIG-dressing on fatigue strength and weld toe geometry of butt welded connections in high strength steel Student: S.H.J. van Es
Flood protection and marine power in the Wash estuary, United Kingdom Student: B. Hofschreuder Impact Assessment of Extreme Storm Events Using a Bayesian Network Student: D. Knipping Ontwerp gekromde roldeur Nieuwe Zeesluis IJmuiden Student: B.M.I. van Kortenhof Decision alternatives for the safety of the Eastern Scheldt Student: W.J. Leeuwdrent Effect of removal of the Oosterschelde storm surge barrier Student: P.D. de Pater
104 | Master’s Theses November 2012
7
Last year’s Theses
Morphodynamics of mega-nourishment Student: T. Pekkeriet Simulating & classifying large-scale spatial sand-mud segregation Student: F. Scheel Alternate-bar formation under superresonant conditions Student: W. Verbruggen Nearshore currents and swimmer safety in the Netherlands Student: R.C. de Zeeuw Impacts of waves and sea level rise on ports due to climate change Student: L.A. Pham
Hydraulic Engineering – COMEM Domain Sediment Dynamics of Beach Cells under Oblique Swell Waves Student: M.J. Armstrong Feasibility of a Marina port along the Buenos Aires coast, Argentina Student: R. Camarena Calderon Technical Feasibility and Economic Potentials of Using LNG as Alternative Marine Fuel Student: L. Jin Mega Container Ships: Implications to Port of Singapore Student: L. Liyenita Widjaja The Mekong Deltaic Coast: Past, Present and Future Morphology Student: P.K.L. Phan
Validation of a practical constitutive model for liquefaction Student: A. Petalas
Watermanagement A framework to assess the realism of model structures using several hydrological signatures Student: T. Euser “Stappen in de afvalwatercalculator” Student: T.W. Padmos Enhancing the applicability of the polder concept Student: E. van der Pal The morphological impact of the creation of a reservoir Student: J. van der Zwet Ceramic Microfiltration Student: M. Li
Transport & Planning Analysis of Pedestrian movements at Lowlands Student: D.C.Duives Possibilities to implement coordination in an adaptive traffic signal control system Student: D. Petres Provinciale Toepassingen voor Wegverkeersgegevens: Student: J. Vries Paramaribo beter bereikbaar Student: M.E. Flu To Tram or Not To Tram Student: T. Bunschoten
Video-based nearshore bathymetry estimation for Rip current forecasting on a macrotidal beach Student: R. Sasso Innovative Structure Solution for Discharge Sluice at Vung Tau Go Cong Viet Student: H.S. Truong
Geo-Engineering Dimensioning of underwater concrete floors Student: R.T. Arkesteijn
105 | Master’s Theses November 2012
7
Last year’s Theses
Master’s Theses March 2012
Civil Engineering theses Building Engineering
Hydraulic Engineering Primary dikes in Limburg Student: L.M. Groendijk
Connecting Modular Floating Structures Student: M.J. Koekoek Adaptibility of structures Student: A.J. van Westenbrugge
Flooding and sediment management on the Koshi alluvial fan Student: E.M. Hooning Erosion in the tide-influenced Rhine-Meuse delta Student: T. Smits
Reinforcement Toolbox Student: J. Lauppe
The Lagos coast Student: K.M. van Bentum
Timber stadium Engineering Student: T. van den Boogaard Medium rise timber buildings in the Netherlands Student: S. van Egmond Structural feasibility of a demountable football stadium Student: M. Loosjes Prestaties van thermisch comfort installaties in NL Student: P.C.M. Zegers
Structural Engineering Vortex-induced vibrations of suspended floating pipelines Student: N.E. Oikou Torsion in ZIP bridge system Student: E. van Vliet
Impact of re-surfacing groins on hydrodynamics and sediment transport Student: A. Hendriks Probabistic Modelling of Extreme Beach erosion using XBeach Student: M. Riesenkamp Edge scour around an offshore wind turbine Student: E. Simoons Process-based modelling of morphological response to submerged breakwaters Student: R.J. Vlijm Dune erosion near sea walls Student: B.B. de Vries Flexible scour protection around cylindrical piles Student: G. van Velzen
Feasibility of using activated paper sludge recycled minerals Student: M. Ahammout
Pre-Posterior Bayesian Analysis Student: S. Al-Baz
Progressive collapse in design of bridges Student: S. van Wijk
Baggerpluimen – Ecologische risicoanalyse Student: J.H. Becker
Interaction between plate and column buckling Student: A. van Ham
The floating construction method Student: R. Hendriksen
Most cost effective connection between arches Blalobridge Student: H.R. van der Land
The feasibility of a commercial osmotic power plant Student: R. Kleiterp
Feasibility of Tall Timber Buildings Student: S.G.C. Timmer
Differences between a 3 dimensional probabilistic and the traditional method of berthing structure design Student: J. Kool
106 | Master’s Theses November 2012
7
Last year’s Theses
Risk to life due to Flooding in post-Katrina New Orleans Student: A.L. Miller
Biofouling and organic micropollutants rejection Student: N.T. Quach
Rip Current Characteristics at the Dutch Coast Student: G. Winter
Operationalization of SoilDTS Student: J.H.A.M. Jansen
Port of Rotterdam Anchorages Study Student: S.B. Devillé
The world’s freshwater resources are threatened Student: M. Hegnauer
Sedimentation in the Botlek Harbour Student: A. El Hamdi
Transport & Planning Study of evacuation behaviour during a flood Student: S.L. Hek
Coal transport Kalimantan Student: B.C. Joppe Analyzing the hydraulic design for the new basin in the IJmuiden outer harbor Student: P. Kaufmann Pump jets in inland vessels Student: J.R.C. Manaois Optimizing the passage of fast ferry navigation at the Schellingwoude lock complex Student: M.J. Rispens Flexible Port Infrastructure on Maasvlakte 2 Student: R. Ros Development Plan Dordrecht Seaports Student: M.J. Verhage
Geo-Engineering Time dependent processes on passive loaded piles Student: K. Siderius Modelling and Effects of Rapid Impact Compaction Student: J. Vink
Watermanagement Analytical Modeling of Salt Intrusion in the Kapuas Estuary Student: F. Gevers Deynoot Moisture Recycling and the effect of land-use change Student: R. Nikoli Memstill for wastewater: Effects of surfactants in the feed solution Student: N.T.T. Hung
107 | Master’s Theses November 2012
7
Last year’s Theses
Master’s Theses October 2011
Civil Engineering theses Building Engineering Application of Higher Strength Concrete in Tubular Structures Student: H. Balbaid Sustainable and Durable Redevelopment Student: E. Bilardie Optimising the design of a steel substructure for offshore wind turbines in deeper waters Student: F.P.M. van Gerven Testing the application of CFD for building design Student: S.R. Hunte
Fatigue damage in the orthotropic steel deck with respect to the trough-to-deck plate joint in between the crossbeams Student: J. Liao Automatic Buckling Checks on Stiffened Panels Based on Finite Element Results Student: O. Hillers Autogenous shrinkage of cementitious materials containing blast furnace slag Student: R.M. Mors
Hydraulic Engineering Morphological modeling of the Atrato river delta in Colombia Student: S. Post
Ultra High Performance Concrete in Large Span Shell Structures Student: R.N. ter Maten
Navigability at an unstable bifurcation Student: F.C.R. Melman
Glass Columns Student: E. Ouwerkerk
On the morphodynamics of Lagos Harbour Student: V. Ballendux
Fatigue Design of FSPO topside details Student: B. Siegler
Tidal divides Student: J. Vroom
Super high-rise in Rotterdam Student: U.M Winter
Risk-based control of salt water intrusion for the RhineMeuse Estuary Student: M. Zethof
Triple-layer membrane structures - Sound insulation performance and practical solutions Student: J.J.E. de Vries
Structural Engineering
Modelling Sediment Transport in the Swash Zone Student: A. van Rooijen Dune erosion near sea walls Student: B. de vries
Shearforce in immersed tunnels Student: D.A.W. Joosten Mega Floating Concrete Bridges Student: A.H. Saleh Communicating ‘structural’ design options Student: T.K. Uijtenhaak Shear Redistribution in Solid Concrete Slabs Student: J. Falbr The effect of the increase of concrete strength in time on the failure mechanism of beams and one-way slabs Student: L.F. Soto
System description Noord-Holland coast, a review of the nourishment strategy applied. Student: R. Pot Modelling decadal barrier island behavior Student: K.W. Pruis Notional Permeability of breakwaters Student: R. Kik Earthquake analysis of quay walls Student: J.W. Liang
108 | Master’s Theses November 2012
7
Last year’s Theses
Preparing a long term management plan for the future of the Slufter Student: R. Heerema
Rainfall fed inundation in greenhouse dominated polders; Research of water system assessments Student: B.C. Albers
The behaviour of a moored oil tanker in the Port of Leixões, Portugal. Student: M. van der Wel
Prediction of temperature distribution in a Drinking Water Network Introduction Student: L. Magda
Interaction between loaded barges and bed material Student: R. J. Lenselink
A new suit for the IJsselmeer Student: J. Talsma
Goederenvervoer over water Student: R. van Liere
A fresh-keeper for Noard Burgum Student: M.J.H. van der Valk
Preliminary study of the flushing operations in the Langmann reservoir, Austria Student: V.J.E. den Boer Process-based modelling of coastal dune development Student: M.C. Muller
Transport & Planning The use of probe data from consumer GPS navigation devices for the analysis of controlled intersections Student: A.M. Meijer
Modelling the interaction between morphodynamics and vegetation in the Nisqually River estuary Student: M. Monden
Geo-Engineering Het opstellen van een richtlijn voor partieel funderingsherstel Student: S. De Lange Time dependent processes on passive loaded piles Student: K. Siderius
Watermanagement Land classification based on hydrological landscape units Student: S. Gharari Urban surface water quality enhancement. Student: M.R. van Dieren Unembanked Areas – A risk assessment approach Student: M. Wolthuis Performance assessment of tree-based model predictive control Student: P.M. Stive
109 | Master’s Theses November 2012
7
Last year’s Theses
Master’s Theses June 2011
Civil Engineering theses Building Engineering Structural feasibility of the Rotating Tower Dubai Student: P. den Besten Double curved precast load bearing concrete elements Student: B. Janssen The effect of steel plate girders with a high slenderness upon the fire resistance Student: R. Wiersum Parkeerkelder met een pneumatisch caisson Student: S.P. Rodrigues Monteiro
Hydraulic Engineering The cause of coastal erosion on a nourished beach in Kololi, The Gambia Student: E. Bijl Influence of the armour layer and core permeability on the wave run-up Student: P.J.M. van Broekhoven Feasibility study on the use of a floating breakwater to protect a new artificial beach in Balchik, Bulgaria Student: R. Drieman Design of berth n.12 in the port of Ventspil, Latvia Student: P. Gatta
Verlevendiging van de binnenrotte door multifunctioneel marktsysteem Student: M.Zoons
Mooring facility ‘Cruiseport The Hague’ Student: H.J. van der Giessen
Cellular beam-columns in portal frame structures Student: J.G. Verweij
Space intensification EMO-peninsula Student: T.M. Henneveld (MSc Hydraulic Engineering)
Structural Engineering
Modelling the equalizing process of rockfill dumps with a plough Student: W. Kranendonk
Plate buckling in design codes Student: M. van der Burg
Morphodynamic analysis of the Ecobeach project Student: M. de Lange
Wind load and high-rise: Student: N. Narain Loading capacity of laterally restrained prestressed concrete slabs Student: R.F.C. de Rooij The effects of the interaction between the substrate and the superstructure of the buildings of project Erasmuspoort Student : R. Soemeer Extension and Verification of Sequentially Linear Analysis to Solid Elements Student: L.O. Voormeeren Stability of a concrete pedestrian bridge with load bearing railings Student: V.M. Weidema Ultra High Performance Fibre Reinforced Concrete for bridge constructions Student: L.W.H. Bouvy
Probabilistic design of settling basins for environmental compliance Student: W. de Lange Verzandingsprobleem in de vluchthaven Wijdenes Student: E. Lee Comparison of quay wall designs in concrete, steel, wood and composites with regard to the CO 2-emission and the Life Cycle Analysis Student: T. Maas Providing current forecasts for the 2012 Olympic Sailing Competition Student: S. Poortman The Effects of The Ike Dike barriers on Galveston Bay Student: M. Ruijs Relatie tussen unity check en faalkans Student: J. De Vlieger
110 | Master’s Theses November 2012
7
Last year’s Theses
Invloed van zandeigenschappen op het piping proces Student: R. van der Zee The morphological effects of Sediment diversions on the Lower Mississippi River Student: M.Bos Stroming van beton in diepwanden Student: J. Mulder
Hydraulic Engineering – COMEM Domain Modeling the Evolution of the Wax Lake Delta in Atchafalaya Bay, Louisiana Student: K. Hanegan The appraisal of climate adaptation measures and coastal management strategies for Durban, South Africa Student: M. A. Geldenhuys Impact of acces of channels geometry on wave penetration in harbours Student: C. G. Mardones Low Frequency Wave Resonance on Fringing Reefs Student: A. W. Mackay Pomeroy
Integrated water management from the treasurer’s perspective Student: J. van Leeuwen Subsurface abstraction in the Amsterdam Watersupply Dunes Student: R. Martens Groundwater dynamics landslides in varved clays Student: J.E. van der Spek
Transport & Planning Micro dynamisch verkeersmanagement Student: I. Bouma Effect van verkeerslichten op turborotondes Student: B. Granneman Line design of the future Student: N. Guis Redesign of the bus station Groningen assisted by a new simulation tool for bus stations Student: J.J.F. Hoogenboom MSc. Futures of Rotterdam South Student: R. Hoogerwerf
Geo-Engineering Experimenteel modelleren van horizontale belastingen op grote diameter monopaal fundaties in zand Student: A. Alderlieste
De overgang van 80 km/uur naar 50 km/uur op de grens bebouwde kom Student: M. de Jong
Piled embankment with Geosynthetic Reinforcement Student: T.J.M. den Boogert
Separation of Freeway Traffic Flows by Dynamic Lane Assignment Student: A.M.G. Soekroella
Grondvervormingen ten gevolge van het maken van bouwputten Student: J. Kimenai
Regional effects on road safety of the RijnlandRoute Student: L.M. van Dijk
Toepassing spanningspadmethode op een horizontaal gronddruk vraagstuk Student: G. Peeters
Around the metro - Research intro the potencies of the metro stops in Rotterdam Student: R.G. van Huet
Negative Skin Friction; Design challenges in Singapore Student: P.J. Spruit
Watermanagement A Decision-Support System based on Real Time Control and Data Assimilation Student: A.L. van Breukelen
111 | Master’s Theses November 2012
7
Last year’s Theses
Master’s Theses February 2011
Civil Engineering theses Structural Engineering
Hydraulic Engineering Integral Design of Work Channels and Basins Student: T, IJsebeart Dredging history of the river Waal and expected future dredging works Student: J.S. Bardoel
Living Tree Buildings Student: Anne Nuijten Application of Ultra High Strength Concrete in LNG Terminals Student: Michel Kortenaar Mechanical behavior of bridge bearings of concrete bridges Student: M. de Boer Winter damage of porous asphalt Student: S.A. Mohan Snap through of large shield driven tunnels Student: T.G. van der Waart van Gulik Traffic induced bearing loads and movements of a steel plate-girder bridge Student: V. Bos The optimization of tripod substructure and its application to two different topsides Student: Wenchao Wang Human Induced Lateral Vibration of Bridges Student: D. Karagiannis
Numerical modeling of wave run-up on a dike Student: I.C. van den Bosch Analysis of costs in new terminals investments Student: C. van Buuren Shell factors for piles subjected to horizontal soil displacements Student: Erik den Arend A comprehensive assessment of Multilayered Safety in flood risk management Student: Frouke Hoss The Gevelco quay wall Student: D. Grotegoed “Feasibility study of a Climate Dike” Student: Larissa Smolders Flood defence town centre Dordrecht Student: M. Hinborch Long-term morphological modelling of the mouth of the Columbia River Student: Emiel Moerman
Building Engineering Covering A28 highway at Amersfoort Student: S.L. Huneker The elevated metro structure in concrete, UHPC and composite Student: R.J.A. Kenter The sustainable refurbishment of bk city Student: M.K. Prodromou A timber bearing structure for ‘Concept House’ Student: A.D. van Wijngaarden
Dynamic behaviour of tunnel elements during the immersion process Student: G.W. Nagel Stimulering provinciale binnenvaart door verkeersmanagement en aanpak knelpunten Student: C. van der Hoog Gaining new insights regarding traffic congestion, by explicitly considering the variability in traffic Student: O.M. Miete Modelling nearshore currents driven by waves and set-up gradients Student: P. van de Linde
112 | Master’s Theses November 2012
7
Last year’s Theses
Morphological Impact of Coastal Structures Student: R. van der Hoeven
Transport & Planning
Post-trenching with a trailing suction hopper dredger Student: K. van de Leur
Gaining new insights regarding traffic congestion, by explicitly considering the variability in traffic Student: O.M. Miete
Port Design Student: R.A.R. Heuts
Accelerating the introduction of electric bicycles Student: Jeroen Loijen
Numerical modelling of turbidity currents in submarine channels Student: Anne Ritsema
Geo-Engineering Laterally Loaded Piles, Models and Measurements 48 Student: J. Ruigrok
Watermanagement Validation of SMOS satellite data over Ghana and Burkina Faso Student: A. Poelstra Onderzoek naar verbrakking Polder Westzaan Student: I. Gozuberk Analyzing the effects of large-scale green roof implementation in Singapore Student: J. van Spengen Clogging of permeable pavements in semi-arid areas Student: M. Amirjani Observing tidal slack in the Scheldt estuary Student: M. Lievens Low cost disdrometer Student: S.A.P. de Jong Swale filter drain system: The inflow – discharge relation. Student: E. A. Donkers Conditioning of aggressive water Student: J.C.J. Gude
113 | Master’s Theses November 2012
Research Groups and professors within the faculty
Research groups and professors within the faculty of Civil Engineering and Geosciences
Specialisation
Name
Telephone 015-27. . . . .
Design and Construction Construction Mechanics Research Group Construction mechanics Dynamics Structural Mechanics
Prof.dr.ir. J.G. Rots Prof.ir. A.C.W.M. Vrouwenvelder Prof.dr.ir. L.J. Sluys
83799 84782 82728
Materials Science and Sustainable Construction Research Group Materials and Environment Prof.dr.ir. K. van Breugel
84954
Road and Rail Construction Research Group Road and Railway Construction
84812
Prof.dr.ir. A.A.A. Molenaar
Building and Civil Engineering Structures Research Group Concrete structures Prof.dr.ir. J.C. Walraven 85452 Concrete modelling & materials Prof.ir. A.Q.C. van der Horst 87014 Timber structures Prof.dr.ir. J.W. van de Kuilen 82322 Steel structures Prof.dr.ir. J. Wardenier 82315 Structural and Building Engineering Prof.ir. F.S.K. Bijlaard 84581 Utility buildings Prof.dipl.ing. J.N.J.A. Vamberský 85488 Product Design Research Group Methodical Design
Prof.dr.ir. M.J.C.M. Hertogh
84921
Prof.dr.ir. G.S. Stelling Prof.dr.ir. W.S.J. Uijttewaal Prof.dr.ir. J.C. Winterwerp Prof.dr. J.D. Pietrzak
81371 81371 84582 89455
Hydraulic Engineering Fluid Mechanics Research Group Fluid Mechanics Environmental hydro informatics Sediment Dynamics Physical Oceanography
Hydraulic and Offshore Engineering Research Group Probabilistic design and Hydraulic Structures Prof.dr.ir. J.K. Vrijling 85278 Coastal Engineering Prof.dr.ir. M.J.F. Stive 84285 Ports and Inland Waterways Prof.ir. T.Vellinga 85075 River morphology & River Engineering Prof.dr.ir. H.J. de Vriend 81541 Hydraulic Engineering Prof.dr.ir. W.S.J. Uijttewaal 81371
114 | Master’s Theses November 2012
Research Groups and professors within the faculty
Specialisation
Name
Telephone 015-27. . . . .
Water Management Sanitary Engineering Research Group Sewerage Waste Water treatment Drinking Water
Dr.ir. F.H.L.R. Clemens Prof. J.H.J.M. van der Graaf Prof.ir. J.C. van Dijk
83347 81615 85227
Prof.dr.ir. H.H.G. Savenije Prof.dr.ir. N.C. van de Giesen Dr.ir. T.N. Olsthoorn
81433 87180 87346
Prof.dr. W.G.M. Bastiaanssen Prof.dr. W. van Vierssen
85717 85080
Prof.dr.ir. B. Van Arem Prof. Ir. F.C.M. Wegman Dr. R.A. Zuidwijk Prof.dr.ing. I.A. Hansen Prof.ir. F.M. Sanders Prof.dr.ir. S.P. Hoogendoorn
86342 83346 85279 81780 85475
Prof.dr. S.B. Kroonenberg Prof.dr. S.M. Luthi
86025 86019
Petroleum Engineering Research Group Oil- and Gas production systems Reservoir Technology Reservoir Engineering
Prof. P.K. Currie PhD Prof. W.R. Rossen Prof.ir. C.P.J.W. van Kruijsdijk
86033 86038
Applied Geophysics and Petrophysics Geophysical Imaging Methods Technical Geophysics
Dr. W.A. Mulder Prof.dr.ir. C.P.A. Wapenaar
83666 82848
Geo Engineering Research Group Groundwater mechanics Foundation Engineering Underground Space Technology Geo environmental engineering
Prof. F.B.J. Barends Prof.ir. A.F. van Tol Prof.ir. J.W. Bosch Prof.dr. J. Bruining
85423 85478 82844 86032
Water Resources Research Group Hydrology Water Resources Geohydrology Water Resources Management and Earth Observations Science System Assessement
Transport & Planning Transport Planning Traffic Safety Transport and Traffic Networks Traffic and Transport Facilities Infrastructure Planning Traffic Flow Theory and Simulation
Applied Earth Sciences Applied Geology Research Group General Geology Production Geology Resource Engineering Research Group
115 | Master’s Theses November 2012
© 2013 – Technische Universiteit Delft Layout NewMedia Centre – Library TU Delft
116 | Master’s Theses November 2012
Collection of Master’s Theses November 2012
Collection of Master’s theses
Civil Engineering and Geosciences Stevinweg 1 PO Box 5048 2600 GA Delft The Netherlands T +31(0) 15 27 85440 F +31(0) 15 27 87966
Faculty of Civil Engineering and Geosciences
November 2012
