Collection of Master's theses

Faculty of Civil Engineering and Geosciences

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

Collection of Master’s Theses October 2011

Collection of Master’s theses October 2011

2 | Master’s Theses October 2011

Master’s Theses Civil Engineering and Geosciences October 2011

Civil Engineering Stevinweg 1 PO Box 5048 NL 2600 GA Delft The Netherlands Telephone: +31 (0)15 2784023 E-mail: [email protected]

2 | Master’s Theses October 2011

Table of Contents Preface What is the graduation book exactly?

Civil engineering theses

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11

Building Engineering

11

Application of Higher Strength Concrete in Tubular Structures Student: H. Balbaid

12

Sustainable and Durable Redevelopment Student: E. Bilardie

13

Optimising the design of a steel substructure for offshore wind turbines in deeper waters Student: F.P.M. van Gerven

14

Testing the application of CFD for building design Student: S.R. Hunte

15

Ultra High Performance Concrete in Large Span Shell Structures Student: R.N. ter Maten

16

Glass Columns Student: E. Ouwerkerk

17

Fatigue Design of FSPO topside details Student: B. Siegler

18

Super high-rise in Rotterdam Student: U.M Winter

19

Triple-layer membrane structures - Sound insulation performance and practical solutions Student: J.J.E. de Vries

20

Structural Engineering

21

Shearforce in immersed tunnels Student: D.A.W. Joosten

22

Mega Floating Concrete Bridges Student: A.H. Saleh

23

Communicating ‘structural’ design options Student: T.K. Uijtenhaak

24

Shear Redistribution in Solid Concrete Slabs Student: J. Falbr

25

The effect of the increase of concrete strength in time on the failure mechanism of beams and one-way slabs Student: L.F. Soto

26

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Fatigue damage in the orthotropic steel deck with respect to the trough-to-deck plate joint in between the crossbeams 27 Student: J. Liao Automatic Buckling Checks on Stiffened Panels Based on Finite Element Results Student: O. Hillers

28

Autogenous shrinkage of cementitious materials containing blast furnace slag Student: R.M. Mors

29

Hydraulic Engineering

31

Morphological modeling of the Atrato river delta in Colombia Student: S. Post

32

Navigability at an unstable bifurcation Student: F.C.R. Melman

33

On the morphodynamics of Lagos Harbour Student: V. Ballendux

34

Tidal divides Student: J. Vroom

35

Risk-based control of salt water intrusion for the Rhine-Meuse Estuary Student: M. Zethof

36

Modelling Sediment Transport in the Swash Zone Student: A. van Rooijen

37

Dune erosion near sea walls Student: B. de vries

38

System description Noord-Holland coast, a review of the nourishment strategy applied. Student: R. Pot

39

Modelling decadal barrier island behavior Student: K.W. Pruis

40

Notional Permeability of breakwaters Student: R. Kik

41

Earthquake analysis of quay walls Student: J.W. Liang

42

Preparing a long term management plan for the future of the Slufter Student: R. Heerema

43

The behaviour of a moored oil tanker in the Port of Leixões, Portugal. Student: M. van der Wel

44

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Interaction between loaded barges and bed material Student: R. J. Lenselink Goederenvervoer over water Student: R. van Liere

45

Preliminary study of the flushing operations in the Langmann reservoir, Austria Student: V.J.E. den Boer

47

Process-based modelling of coastal dune development Student: M.C. Muller

48

Modelling the interaction between morphodynamics and vegetation in the Nisqually River estuary Student: M. Monden

49

46

Geo-Engineering 51 Het opstellen van een richtlijn voor partieel funderingsherstel Student: S. De Lange

52

Time dependent processes on passive loaded piles Student: K. Siderius

53

Watermanagement 55 Land classification based on hydrological landscape units Student: S. Gharari

56

Urban surface water quality enhancement. Student: M.R. van Dieren

57

Unembanked Areas – A risk assessment approach Student: M. Wolthuis

58

Performance assessment of tree-based model predictive control Student: P.M. Stive

59

Rainfall fed inundation in greenhouse dominated polders; Research of water system assessments Student: B.C. Albers

60

Prediction of temperature distribution in a Drinking Water Network Introduction Student: L. Magda

61

A new suit for the IJsselmeer Student: J. Talsma

62

A fresh-keeper for Noard Burgum Student: M.J.H. van der Valk

63

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Transport & Planning The use of probe data from consumer GPS navigation devices for the analysis of controlled intersections Student: A.M. Meijer

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65 66

Preface

For graduates is the master thesis the final part of their study. With their thesis they prove that they are ready to receive the title of Master of Science. The previous years of study at our faculty have given them the skills and the knowledge to complete this important task. All the theses presented in this book reflect the high quality of our graduates. They have not only addressed relevant problems of society, but also presented innovative solutions. Their theses reflect their capabilities and their readiness to start their careers. For the faculty of Civil Engineering and Geosciences the presented thesis are important to prove the societal relevance and quality of our educational programme. The high standards we pursue at our faculty can be found in throughout this book. Relevant issues like coping with climate change, sustainable design and are skillfully addressed by our graduates. By also providing solutions they reflect one of the aims of our faculty, to contribute to the progress of society. Currently I am very proud to present our graduates in this book, and I wish them good luck in continuing their valuable work in society. Prof.ir. Louis de Quelerij Dean of the Faculty of Civil Engineering and Geosciences

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8 | Master’s Theses October 2011

What is the graduation book exactly? “Master’s Theses February” 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 February 2011”, 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 six specialisations: •• Structural Engineering •• Building Engineering •• Hydraulic Engineering •• Geo Engineering •• Water Management •• Transport & Planning

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. If you so wish, you can also make an appointment to view a particular thesis. 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

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). 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. 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.

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1. Civil Engineering theses

Building Engineering

1

Building Engineering

Application of Higher Strength Concrete in Tubular Structures

The use of concrete in high-rise buildings has the advantage of being able to build rather stiff and fire proofing structures thanks to the large applied amount of concrete. Structural stiffness is important in high-rise structures since the maximum lateral displacement at the top has to be limited to meet the required comfort level in a building. An often-used type of structure is the framed tube structure. Several studies have pointed out that the tubular structure is able to achieve great heights. It highly improves the building’s stiffness, resulting in less lateral displacements. In the last decades, higher buildings are being built in seeking the ultimate height limit of a structure. While buildings were being built higher and higher, the quest for higher quality materials continued as well. Until now, many new types of concrete have been developed, which have better properties than its predecessors. This thesis applies two new types of concrete in a framed tube structure, namely High Strength Concrete (HSC) and Ultra High Strength Concrete (UHSC). It appears that higher strength concretes can be applied in the structure. Its behaviour changes since the higher strength concretes have a different modulus of elasticity. The structures are proven to give better performance: the lateral displacements reduce and higher structures can be built while still fulfilling the requirement to maximum deflection.

Student: Thesis Committee:

Obviously, the higher strength concretes come with a higher price. Consequently, the structure becomes more expensive. However, thanks to the better material properties, the building can be built higher. To acquire knowledge in whether the higher building is feasible, the costs per floor are calculated. A higher building contains more commercially available area and the analysis shows that the costs per unit floor area decrease by 14% if HSC is applied. Despite the fact that the building with an UHSC structure contains more commercially available area, it is not beneficial due to the high price of the UHSC mixture: the costs increase up to 25%. The most important recommendation is to utilise the material properties of the higher strength concretes as much as possible. This is achieved by applying a hybrid structure: combining higher strength concrete with ordinary concrete in one structure. The thesis shows that the application of higher strength concretes in framed-tubular structures is possible. It provides better performing structures and, in some cases, a reduction in costs. While the HSC models proved to provide a good performance to costs ratio, the UHSC models currently do not.

H. Balbaid Prof.ir. R. Nijsse (TU Delft), Dr.ir.drs. C.R. Braam (TU Delft), Ir. K.C. Terwel (TU Delft)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Sustainable and Durable Redevelopment

In this MSc thesis report an investigation is done to the possibilities in changes for industrial heritage in The Netherlands. Main thought behind the research is to investigate all facets and possibilities of industrial buildings; creating really sustainable buildings. The thesis describes main subjects about the re-use of monumental industrial heritage. The subjects range from knowledge of the history of buildings to existing building regulations and many more relevant building aspects. In addition, three case studies have been investigated with the so called ‘DuMo-calculation model’. The three case studies are all projects from IMd Raadgevende Ingenieurs and they have been compared on environmental costs in comparison to each other and a degradation-built scenario. The DuMo-calculation model which has a Greencalc+ background, compares building aspects like material, energy and water.

Lastly a scenario study is added to the research of the case studies. This scenario study includes a comparison in sustainability between re-used buildings versus newly built buildings. The main conclusion of the scenario study is the enormous reduction in the amount of applied materials in the re-used building compared to the newly built building, hence a significant lower environmental impact when re-using a building. These findings are in line with the aim of a structural engineer to efficiently apply materials in structures and optimize the use of the various properties of materials.

KNOWLEDGE A good estimation of the quality and the bearing capacity of an existing building structure and a foundation leads to a more efficient use of the existing building. Knowledge about the old and current building regulations is necessary in order to maintain and use the existing building structures as much as possible. CREATIVITY The thesis highlights several projects in which in a creative way a new function is realized in an existing building. Creativity exposes itself in structural solutions as well in climate design solutions. Hereby should be mentioned that a good structural solutions is not always the most complex solution but the most simple one. For example, change the flow of forces in an existing building structure as less as possible. AMBITION To make a project to a success, besides knowledge and creativity, ambition is a very important aspect. The most important ambition to be sustainable, the main thought should be: The most sustainable building is no building at all.

De conclusions of the research are summarized in three themes; knowledge, creativity and ambition. For each theme guidelines are described which are relevant for the structural engineer who is involved in the re-use of building structures. Next a description follows for the main conclusions of each theme.

Student: Thesis committee:

E. Bilardie Prof.dr.ir. E.M. Haas (TU Delft), Ir. R.H. Wiltjer (IMd Raadgevende Ingenieurs), Dr.ir. A. van Timmeren (TU Delft), Ir. S. Pasterkamp(TU Delft)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Optimising the design of a steel substructure for offshore wind turbines in deeper waters

Introduction In the need for more green energy a prominent role is reserved for wind energy. Offshore wind energy in deeper waters capitalises on more efficient wind properties and increased public acceptance compared to onshore wind energy and wind farms close to shore. In the coming years the offshore wind market is expected to evolve rapidly, especially in the deeper water range of thirty to sixty meter.

Objective In a business case preceding to this study as first reference a jacket type substructure was designed for a 6 MW turbine in a water depth of sixty meter. The goal of this thesis is to reduce the cost of this reference design in total use of material and assembly. Also the transportation and installation of the substructure are taken in consideration.

Research & results First a step back is taken to reconsider the structural concept of the reference design. Several substructure concepts, like tripods and straight-leg jackets, have passed the review and firstly qualitative weighed against primary criteria in a Multi Criteria Analysis and subsequently by FEM based in-place analysis. The outcome of the total substructure weight and natural frequency with respect to frequency of wave loading and turbine excitement determined the decision to further investigate a three-leg and four-leg battered jacket. Thereto a fatigue analysis was performed. The calculation method used at the original reference design to determine the total fatigue damage due to turbine and wave loading was proven to be too optimistic and therefore modified. In relation to the reference design several optimisations have been proposed, including applying a horizontal brace just above mudline level, applying double sided butt welds and adopting K-bracing instead of X-bracing.

Student: Thesis Committee:

Finally, four designs have been worked out; the reference design (without optimisations), an optimised four-leg jacket, four-leg jacket with k-braces and a threeleg jacket. The total assembling cost of each design is calculated by considering the handling time and the welding volume with corresponding welding time of each weld. Together with the material use the total fabrication cost is assessed. The jacket shall be transported offshore by a standard North Sea barge. The dimensions of this barge potentially enable the transportation of three four-leg jackets and four three-leg jackets. Depending on the wind farm location this may lead to reduction of one tug and transport barge case of the three-leg jacket. Further consequence of the three-leg jacket is that a foundation pile less needs to be driven. Thereto is the installation time of the three-leg jacket reduced, resulting in less installation cost.

Conclusion By combining fabrication, transport and installation cost it is possible to compute an overview for substructures cost in a complete wind farm. Final conclusion is that the fabrication cost are decisive compared to the installation and transport cost. The four-leg jacket with K-braces turns out to be the most inexpensive design, respectively followed by the thee-leg jacket, the optimised four-leg jacket and the reference design. It is expected that the four-leg jacket with K-braces brings total cost reduction of approximately nine percent compared to the reference design.

F.P.M. van Gerven Prof.ir. F.S.K. Bijlaard (TU Delft), Prof. Ir. C.A. Willemse (TU Delft), Ir. R. Abspoel (TU Delft), Ir. J.N.P.T. Beckers (Hollandia), Ir. S.J.H. Beukers, (Iv-Oil&Gas)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Testing the application of CFD for building design

Introduction The first description of the principles of fluid dynamics has been presented in the 18th century. The first steps in the field of wind engineering were made two centuries ago. In the 1960s the first atmospheric boundary layer wind tunnel has been used. The numerical method Computational Fluid Dynamics (CFD), in its simplest form, dates back to the 1930s. However, only several decades ago, in the 1980s, CFD was introduced in the field of wind engineering. The timeline above is illustrative for the developments in the determination of wind loads on buildings. Compared to other assessment methods for this purpose, CFD is still in its infancy. Infancy always goes hand in hand with childhood problems.

Problem definition With the rise of the computer and its applications CFD has been used by multiple companies to determine wind loads on structures. Often the employees of the companies do not possess enough knowledge to make sound choices throughout the determination process and interpret the output such as the image below. Consequently, this leads to speculations instead of information and accuracy.

three different ways. First, theory is discussed. Second, the influence of modelling choices is discussed and third, assessment methods are compared.

Results 1. Recommended actions for a guideline on postprocessing steps are provided. 2. It has been determined that, for performed simulations, the wall-adjacent cell height did not significantly influence the velocity profiles nor did it significantly influence the determined pressures on the facades of the modelled building. 3. It has been determined that, for the performed simulations, the inlet velocity profile influences the results more than the value of the roughness height at the ground boundary. 4. Regarding turbulence modelling, it has been concluded that results determined with a simulation based on the Reynolds Stress Model (RSM) describes the flow of air around a building better than a simulation based on the Realizable k-E model. For a relevant part, the differences are ascribed to the isotropic behaviour of the Realizable k-E model and the anisotropic behaviour of the RSM. 5. It has been observed that grid sensitivity analysis should be performed for each turbulence model.

Conclusions and recommendations

Research The goal of this thesis is to contribute to the understanding of the method CFD by engineers in determining wind loads on structures and ideally contribute to the development of a future design tool. The thesis attempts to increase the understanding in

Student: Thesis Committee:

The comparison of simulations and assessment methods has provided improved understanding of the use of CFD in building design. However, since limited information on the existence, and if so on the magnitude, of flow features is available, additional research is recommended before other conclusions can be drawn. For this thesis only normal approaching flow is considered and mean pressure coefficients are determined. For other conditions the RANS simulation method is less fit for the description of the flow around and pressures on the building as unsteady vortices are present. It is recommended to test the performance of the RANS method and other simulation methods for these conditions. This also holds in case pressures are determined on the faces where separation, recirculation and reattachment occur.

S.R. Hunte Prof.dipl.ing. J.N.J.A. Vambersky (TU Delft), Ir. C.A. van Bentum (TNO), Ir. H.R. Schipper (TU Delft), Prof.dr.ir. C.P.W. Geurts (TNO, Eindhoven University of Technology), Prof.dr.ir. L.J.Sluys (TU Delft), Ir. R.P.J.O.M. van Rooij (TU Delft)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Ultra High Performance Concrete in Large Span Shell Structures

Ultra High Performance Concrete (UHPC) is a contemporary concrete with a high compressive strength, tensile strength and Young’s modulus combined with extraordinary ductility and a far more durable character than conventional concrete. This high performance material offers a high potential for sustainable and economical applications with slim designs which are capable of resisting heavier loads and span larger areas. Shell structures are spatially curved surface structures which derive their strength from their shape and which resists loads by developing stresses in their own plane. Shell structures can be referred to as ‘form resistant structures’ which present immense structural and architectural potential. The optimal material use leads to designs with a relatively small thickness for which the dimensioning is mostly governed by requirements involving buckling capacity.

The aim of the thesis was to investigate, analyze and report on the potential for UHPC in large span shell structures. After deliberation on the characteristics of UHPC and theory on shells a complete structural design was made for a dome with a span of 150m. The effects of multiple design aspects were investigated and optimized by FEM-analysis.

Student: Thesis Committee:

For the design it was chosen to apply prefabricated elements which are connected by standard bolt- and rebar-anchors which can resist tensile stress due to wind load and guarantee a watertight connection by the compression of neoprene gaskets. The elements are

equipped with thicker element edges which ultimately form ribs stiffening and are subjected to external influences, making use of the durable characteristics of UHPC. It was concluded that the structural design, with a height of 37,5m, will satisfy the structural demands by the application of prefabricated elements with an overall thickness of 35mm and stiffening ribs of 60x180mm2, leading to a total equivalent thickness of merely 44mm. The high potential of the application of UHPC is shell structures is however not solely seen for the material savings but also applies for the low demands on foundation and base requirements, more economic transport and a large reduction on construction time, for which a potential method is developed. Ultimately, the conclusions for the structural design are applied for the improvement of a preliminary architectural design for a large sports facility in Leeuwarden.

R.N. ter Maten Prof.dr.ir. J.C. Walraven (TU Delft), Ir. J. van der Windt (Zonneveld Ingenieurs), Ir. S. Pasterkamp (TU Delft), Dr.ir. P.J.C. Hoogenboom (TU Delft), Dr.ir. S. Grünewald (TU Delft, Hurks Beton)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Glass Columns

A fundamental study to slender glass columns assembled from rectangular monolithic flat glass plates under compression as a basis to design a structural glass column for a pavilion In the world of structural engineering glass is an innovative material. Compared to other conventional structural materials like concrete, steel and timber, it is especially the transparency property that makes it a valued material. Due to the increasing demand for transparency in contemporary architecture, much more structural components as beams, plates, portals and columns are developed in glass. Besides the transparency property, the brittleness of glass makes it essentially an unsafe structural material as the residual capacity is limited. Therefore, the structural glass column is still in its early phases of development. As architects and clients, in general, do not like columns, they are said to block the view and stand in the way. Engineers need to add columns to buildings to provide support. These conflicting desires can be solved by developing a more attractive column, a glass column. The aim of this research project was to focus on further knowledge and understanding of the structural design aspects specifically related to structural glass columns and, on the basis of these findings, to design a glass column as a structural element in a pavilion. The considered slender columns were assembled from rectangular monolithic flat glass plates into different configurations. An exploratory study to the design aspects of glass columns was performed by doing experiments. Onemetre-high glass columns were assembled from glass plates 8 millimetres thick, 100 millimetres wide and 1000 millimetres long and glued with a two-component adhesive based on epoxy resin (Araldite 2000 PLUS 2013) into five different configurations. These columns were compressed by a test bench with felt as the interlayer material to distribute the stresses uniformly over the cross-sectional area. A thorough analysis of the columns and their structural behaviour resulted in four

Student: Thesis Committee:

design aspects that should be considered in the design process of a structural glass column: •• a difference in the vertical position between the assembled glass plates; •• susceptibility to peak stresses at the edges of the glass column; •• the stiffness properties of the glue; •• imperfections like holes and scratches. A two-dimensional numerical model was developed to study two of the considered design aspects. The effect of a difference in the vertical position between the assembled glass plates (which results in protruding edges) and the stiffness properties of the glue on the stress development in the glass were studied. Another series of experiments was performed to study the effect of several design options on the load bearing capacity of the column. The experiments revealed that, among others, avoiding the chance of uneven loading due to a difference in the vertical position between the glass plates and applying an adhesive with low stiffness results in more uniformly distribution of the stresses over the glass column. Finally, the findings of the experimental and numerical investigations were integrated into the structural design of a glass column for a pavilion. The preliminary design of a pavilion, which consists of ten columns, served as a context for the structural glass columns (each four metres high). Two main aspects were distinguished in the design process of the column: the boundary connection system and the related cross-section. Finally, a safety concept was developed for the monolithic glass column by applying an outer layer of safety glazing around the structural glass column. To conclude, from this research it is found that different design aspects play an important role in the bearing capacity of slender glass columns assembled from rectangular monolithic flat glass plates. On the basis of the experimental and numerical results the most relevant aspects related to designing a structural glass column were listed in the report.

E. Ouwerkerk Prof.ir. R. Nijsse (TU Delft), Dr.ir. M.A.N. Hendriks (TU Delft), Dr.ir. F.A. Veer (TU Delft), Ir. S. Pasterkamp (TU Delft), Ir. L.I. Vákár (Movares)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

17 | Master’s Theses October 2011

1

Building Engineering

Fatigue Design of FSPO topside details

FPSO design has shown a fast development in recent years. The concept is more and more frequently used for deepwater solutions all around the world. The weather conditions and the water depth are varying on a broad scale, from the warmest point on Earth, to the coldest ice conditions of the North. The process of drilling, excavating and separating crude oil from the seabed requires a sophisticated technology. The chain of process equipment is very long, and highly complex. To wind up all the necessary equipment on a floating vessel, the topside modules are designed in a way, where the available space in all three dimensions is used efficiently. FPSO topside structures are heavily loaded, large size steel structures. All FPSO’s are operating in different conditions and sea states, which requires different hull structures. These conditions result in unique topside designs; all modules are individual and not reproduced structures. The geometry and detail connections of the topside modules are both individual solutions.

Student: Thesis Committee:

These unique solutions require precise design, calculations and verifications. The significant failure mode of these steel structures is fatigue, as the repetitive wave loading causes stress fluctuation in the members. To determine the fatigue life of such a complex connection as the module’s main structure’s, one needs to assess the hot spot stresses as accurately, as possible. In order to do this, the best method is the precise finite element modelling of the connection. The thesis has assessed the offshore structural background of the topside module structures, and the theoretical background required for conducting a fatigue analysis of the modules. A short review is presented of the Fatigue Limit State analysis performed by Chicago Bridge & Iron B.V. during the Skarv-Idun FPSO project. The analysis is investigated by means of comparative analysis. General beam-and-column and detailed finite element models are built for purpose. The internal stresses of the module are determined, and together with the Stress Concentration Factors of a particular joint, simplified fatigue analysis is performed. The results are evaluated separately, and then compared to the existing results. Based on the findings, an improved method of the fatigue life evaluation is proposed.

B. Siegler Prof.ir. F.S.K. Bijlaard (TU Delft), Dr. M.H. Kolstein (TU Delft), Prof.ir. C.A. Willemse, MBA, Dr.ir. P.C.J. Hoogenboom (TU Delft), ir. Maarten Witteman (TU Delft)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Super high-rise in Rotterdam

There is large difference in height between high-rise buildings in the Netherlands and high-rise in other continents such as North America and Asia. The tallest building in the Netherlands, the “Maastoren”, has a height of 164.75 m whereas in the rest of the world buildings with a height of more than 300 m are not uncommon. In Dubai the Burj Khalifa has even reached a height of 828 m.

Each high-rise project is unique and depends on the many location-bound conditions which influence the choices made in the design of a tall building. Because of this the following question is asked: “Is it tech-nically possible to achieve similar heights in the Netherlands?”. In order to answer this question the goal of this thesis is to deliver the structural design of a tall building with a predetermined height of 800 m. The following research was done: 1. After a location for the tower had been found in the Rijnhaven a literature study was done on the different aspects which are important for high-rise. 2. Researching the different types of structural materials, elements and systems led to the discovery of the several aspects which become increasingly important as the height of the building increases. 3. These aspects were then used as guidelines in the structural design of the building and led to a structural concept of a pile-and-raft foundation and a compound structure consisting of several towers connected across the height of the building. Firstly a footprint for the tower was designed. Three structural alternatives were compared using the finite element program ESA SCIA Engineer. After comparing and examining the deformations, forces accelerations and settlements it was found that the deformations due to the quasi-static load of the 800 m high building for alternative core-outrigger system and diagrid are still within the limits of 1/500 or 1600 mm. However, the accelerations at the top of the building become very large and do not satisfy the criteria concerning accelerations in NEN 6702. Also the settlements were calculated for a shallow foundation and found to be very large The accelerations at the highest occupied floor at a height of 800 m are too large and therefore the building does not satisfy the criteria found in NEN 6702. In the design of both the superstructure and the foundation a lot of assumptions and decisions were made. For the superstructure these mostly have to do with aerodynamics and need to be researched further with the help of wind tunnel.

The Netherlands vs. abroad

Student: Thesis Committee:

U.M Winter Prof.ir. R. Nijsse (TU Delft), Ir. K.C. Terwel (TU Delft), Ing. H.J. Everts, Ir. S. van Eerden (ABT)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

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1

Building Engineering

Triple-layer membrane structures - Sound insulation performance and practical solutions

Introduction & problem definition This report describes a Master’s Thesis research that has been carried out to gain insight in the possible improvements of sound insulation of membrane structures, which are used in practice for temporary structures, e.g. festival tents, and to give practical solutions.

Conclusions

Research This research concentrated on triple-leaf membrane systems with filled cavities. From a state-of-the-art review can be concluded that triple-leaf membrane systems, when filled, perform better than double-leaf and single-leaf membrane structures. From literature research it was concluded as well that tension in the membrane has a negligible effect on the sound insulation and that, on the other hand the flow resistance both of the filling and of the membrane material has large influence.

A well performing triple-layer membrane system was discussed, which met the restriction of 7kg/m 2 for the surface density of the membrane package. This system includes one layer of aerogel for reasonable sound insulation at low frequencies, and one thicker layer of glass wool yielding good sound insulation at higher frequencies. This system is only investigated theoretically for now and not empirically (yet).

Detailing and practical solutions Details have been worked out for a number of practical membrane structure applications for this result (also applicable to variants using only glass wool), focussing on temporary (festival) tent structures.

Results Three different kind of filling materials were used in the present study: (lightweight) glass wool, polyester wool and aerogel. Acoustical measurements were carried out in a laboratory, of which the outcomes were compared to a number of computer and mathematical models. The Multiple Layer Model appears to give good prediction for filled triple-layer membrane systems and this model therefore was used to optimise the important parameters.

Student: Thesis Committee:

J.J.E. de Vries Prof.ir. R. Nijsse (TU Delft), Ir. H.R. Schipper (TU Delft), Dr.ir.arch. M.J. Tenpierik, Ing M.R. Lautenbach (Peutz bv), ir. R. Houtman (Tentech bv)

For further information, please contact the section of Building Engineering tel. 015 - 27 83990 Email: [email protected]

20 | Master’s Theses October 2011

2. Civil Engineering theses

Structural Engineering

2

Structural Engineering

Shearforce in immersed tunnels

Introduction With the introduction of the Eurocode, different formulas are used for shear tests in concrete structures than the previous Dutch standard. These formulas are often used in new building designs. If the result compared with the Dutch standard is either favorable or unfavorable, the design should be modified. It is interesting to research the impact of new formulas applied to existing structures. In certain situations the structural safety has to be reviewed and the use of Eurocode could apply.

Research This research compares four methods of calculation for the shear test in an existing immersed tunnel. The four methods of calculation are based on the Dutch standard, the Eurocode, the IBBC method and a finite element calculation with the program Atena. In addition also the effects of fire on the shear test are considered. The reference project is the Maastunnel, the oldest immersed tunnel in the Netherlands. To compare the different methods properly a unity check is used. The load on the structure is divided by the maximum load that the structure can bear. The construction is safe when the unity check is less than 1. By the results of the unity check it is possible to draw conclusions about the safety of the construction according to the different methods.

Results The most critical parts of the structure are near the corners in the roof. The results of the tests are shown in figure 1. Three methods meet the requirements of the shear test and therefore show that the construction is safe, only the Eurocode (EN) does not.

Figure 2 shows the result of a calculation with Atena. This shows that the construction has a unity check of 0,4 (safe) and more important, shear failure is not dominant.

Conclusions and recommendations The shear test for the current immersed Maastunnel results in roughly the same safety features for the current Dutch standards, the IBBC formulation and the finite element method in Atena. The shear test by the new Eurocode shows a clearly lower safety. Main reason is that according to Eurocode, the contribution of the strength of concrete and reinforcing steel should not be added. For the authors of the Eurocode, testing of existing structures was not the starting point. The finite element method shows that the vault function has a major influence on the ultimate failure behavior. If an arch can occur, the shear strength would increase significantly. The shear strength is strongly influenced by the geometry of the corner of the roof. A frequently used general formulation for the shear tests, results in the use of tests which are not designed specifically for the type of construction. This may result in an unnecessarily amount of reserve, while construction is actually stronger than predicted by the test. The influence of fire on the shear test is limited if the structure can deform. Even if splashing of concrete occurs, a vault can add significant strength. It is shown that prevented deformation has a major influence on the shear test. For tunnels a certain degree of foreclosure cannot be neglected. The assumption that the tunnel deformation by fire is completely forbidden, will require too conservative results. It is therefore recommended to examine the foreclosure rate in order to calculate the additional internal forces.

Student: Thesis Committee:

D.A.W. Joosten Prof.dr.ir. J.C. Walraven (TU Delft), dr.ir. C.B.M Blom (TU Delft), dr. ir. K.J Bakker (TU Delft), Gemeentewerken Rotterdam For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

22 | Master’s Theses October 2011

2

Structural Engineering

Mega Floating Concrete Bridges

This graduation project has been initiated to research the technical feasibility of floating bridges. The project has been done in co-operation with the FDN engineering company and Delft University of Technology. A design is made of a continuous pontoon floating bridge, which connects a mainland to an island. Floating bridges can be constructed where conventional bridges are impractical. The buoyancy forces support the bridge in the vertical direction and the mooring system in the horizontal direction. The project contains also a survey of the most known floating bridges in the world. Environmental loads are the main loading on the floating bridge. Because of the random form of the sea wave forces and the wind force, it is difficult to expect the precise value and direction of loading on the bridge. The environmental loads twist the bridge and excite it in the horizontal and in the vertical direction. When it is possible to construct a sliding pile mooring system to introduce the wind and wave load in the horizontal direction, the floating bridge will have a satisfactory stability. In most cases, it is impossible to construct the sliding piles due to the large water depth or the seabed soil weakness; therefore, the mooring system should be replaced by chains/cables mooring system to maintain the lateral supporting. The efficiency of the mooring cable is lower than the sliding pile due to the relatively large compliance range. That is valid also for the vertical displacement; the bridge response will be introduced by the bridge flexural rigidity, the bridge mass, the water spring, the water damping and the pontoon connector stiffness when discrete pontoons are used. The linear theory is applied to determine the sea wave load. The hydro-static and the hydro-dynamic analysis of a multi-body slender structure consisting of rigidly or flexibly connected elements is made. The behavior of the continuous pontoon floating bridge under the wave and wind load and the connections between the elements are examined. The design procedure of the mooring cables of the offshore structure is applied to design the mooring system.

Student: Thesis Committee:

In vertical direction, the bridge response is influenced by the ratio of the rotational stiffness of the pontoon connector to the flexural stiffness of the pontoon. In horizontal direction, the mooring system stiffness is governing. A highly flexible pontoon connector is described. It contains prestressing cables that provide an elastic spring to keep the original position of the pontoons. The additional function is to absorb the wave forces. The maximum allowable horizontal movement of the bridge can be determined by the diameter and the geometrical dimensions of the mooring cable. The mooring cables demonstrate non-linear behaviour since their stiffness is determined by the force exerted. Embedment steel crossheads are used to introduce the large mooring line forces without damaging the concrete walls of the pontoons. The construction of a slender structure on an unlimited flexible foundation such as water has a certain risk. Material fatigue depends on the range of the stress variation and the loading recurrence which they should be also controlled to ensure the service life of the structure. Because of dealing with a hydraulic structure, an additional relevant condition will be the concrete crack width. Water leakage in the pontoon should be prevented totally in all loading cases. A floating bridge is a cost-effective solution. In most cases, a floating bridge is stable under traffic loads, but the environmental loads (wind- and wave loads) represent the critical load cases.

A.H. Saleh Prof.dr.ir. J.C. Walraven (TU Delft), Dr.ir. C. van der Veen (TU Delft), Dr.ir. C.R. Braam (TU Delft), Dr.ir. P.C.J. Hoogenboom (TU Delft), Ir. D.L. Tirimanna (FDN Engineering), Ir. L.J.M. Houben (TU Delft)

For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

23 | Master’s Theses October 2011

2

Structural Engineering

Communicating ‘structural’ design options Using dashboard portals for exploring alternatives.

Introduction

Results

The thesis consists of two parts; first there is an investigative study that focuses on the multi-disciplinary approach of building projects, second there is the design and development of a tool that has been developed for communicating alternatives in multi-disciplinary optimisation projects. Furthermore the tool brings out the information that would be valuable for a structural engineer to have presented in searching for the ‘optimal’ multidisciplinary solution.

With parametric design there is the possibility to automate the process of changing all parameters and let the computer crunch through all options. This will generate the data needed for further examination. To go through all these options is too tedious; dashboard technology combined with databases can solve this problem in a very graphical/visual way.

Problem definition The aim is to design a program with which parametric design can be evaluated (by an expert), and even on a multidisciplinary level can be used to reach the ‘most desirable’ solution, while having an understandable range of solutions in which the criteria and relations guide one’s gut feeling in selecting the outcome. This range will then bring common tendencies of understanding of the criteria to light, and the effects the relations have concerning the outcome.

Research The research will explore the possibilities of dashboard technology to gather information and display this in such a way that it will help the user making decisions. Inspired by the idea of what we do is based on what we know the alternatives shown on the dashboard will help us making precedents for the project that is being designed. The multi-disciplinary set up of the program will enable the user to understand the communication between the various disciplines involved, as well as being able to explain others parties why certain choices are made and how the design would benefit from this.Being able to convince the other parties involved and to arouse emotions is very important, all disciplines should have similar or the same tools to achieve this. Nowadays the structure of the process in building design can have a high impact on the relations between the different parties, forcing people away from their own specialisations into taking on a more multi-disciplinary designer role.

Student: Thesis Committee:

Their strength is to output all the data and have multiple users understand in a glance where the focus areas should be. This will lead to better substantiated decisions where the relation between choice and consequence is much clearer. Besides that it provides the possibility to dive deeper into the data and extensively explore visual aspects (renders/videos), timelines or graphs (trends, pivoting points and black swans), which is very helpful in showing other parties where the highest profit can be expected.

Conclusion and recommendations It is very important to acknowledge that technology will enable us to develop these kinds of software. This is only a start however, and the interoperable software does not yet fully exist but it is ever closer to becoming a reality.

T.K. Uijtenhaak Prof.dr.ir. J.C. Paul MBA (TU Delft, Arup Amsterdam), Dr.ir J.L. Coenders (TU Delft, Arup Amsterdam), Ir. J.W. Welleman (TU Delft), Dr.ir. R.M.F. Stouffs (TU Delft)

For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

24 | Master’s Theses October 2011

2

Structural Engineering

Shear Redistribution in Solid Concrete Slabs

Introduction and problem definition A raising number of concrete bridges around the world have been subjected to increasing traffic loads during the last decades. There are no doubts, that the replacement or rehabilitation is necessary. Even though, this problem has been discussed for longer time, the main questions about the shear carrying capacity of deck and accuracy of related theoretical predictions still prevail. Accurate design assessment is therefore the key element for the safe predictions and economic issues. The graduation project was conducted at the Faculty of Civil Engineering and Geosciences at Delft University of Technology. This thesis was created with cooperation of the concrete structures department, where related experimental testing has been conducted.

Research The results from the experimental measurements show that the code predictions of the shear redistribution in the concrete slabs (~ bridge deck) underestimate the shear carrying capacity. This work tries to support this statement by nonlinear finite element analysis with a special focus on the shear redistribution and related effective width. Hence, the main tasks of this work are: 1. Simulation of experimental setups by FEM models in order to obtain the same or similar results as in the experiment. 2. Effective width assessment 3. Comparative study between several code predictions and obtained results both from the experiment and modeling. 4. Investigation of problematic issues related to the FEM modelling (fracture energy, tension stiffening).

Conclusions 1. The NLFEA models give an excellent agreement with the experiments in terms of load – displacement behaviour, crack pattern, load carrying mechanisms and the effective width. 2. Codes underestimate the shear carrying capacity of slabs both for one-way shear and punching shear failure. This statement is supported by both experimental results and FEM modelling. 3. Empirical assumptions of shear redistribution under 45° do not satisfactorily agree with many of the test results and the influence of some governing parameters is not suitably reflected. The inaccuracy has been reached particularly if stress redistribution from far face of loading plate is assumed.

Student: Thesis Committee:

J. Falbr Prof.dr.ir. J.C. Walraven (TU Delft), Dr.ir. C. van der Veen (TU Delft), Dr.ir. M.A.N. Hendriks (TU Delft), Ir. E.O.L. Lantsoght, Ir. L.J.M. Houben (TU Delft)

For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

25 | Master’s Theses October 2011

2

Structural Engineering

The effect of the increase of concrete strength in time on the failure mechanism of beams and oneway slabs Introduction

Results

Many solid concrete deck slab bridges exist in the Netherlands which are more than 50 years old. Structures of this type were usually built without shear reinforcement due to practical considerations. As a result their shear capacity relies from materials point of view only on the concrete and its strength. At the same time, it is known that concrete has the characteristic to increase its strength throughout time due to continuing hydration. This poses the idea that the shear strength of this type of structures also increases proportionally in time.

Problem definition This study focuses on investigating if the increase of concrete strength in time increases the shear capacity of beams and one-way slabs sufficiently, so that after some increase in concrete strength there is a change in the governing failure mechanism from shear to bending.

Research The approach of the research is three-fold. One structure has been studied taking into account the increase of the strength of the concrete in the deck of the viaduct. First, by considering the formulations from design codes with respect to its shear and bending capacity. Afterwards, simplified two dimensional non-linear finite element analyses have been implemented in order to investigate the failure mechanisms of the viaduct in a more realistic manner. Finally, three-dimensional analyses were performed in order to study the transverse distribution of loads more accurately.

Student: Thesis Committee:

The results exhibit a change in the governing failure mechanism of the structure from shear to bending when the concrete strength increases due to its ageing. With the non-linear finite element analyses it is found that the actual capacity of the structure in shear is much higher than as predicted by design codes. The 3D non-linear finite element analyses show that practically no change in the transverse distribution of loads occurs in the structure for different load levels.

Conclusions and recommendations It is concluded that the ageing of the concrete increases largely the shear capacity of the structure, so that a clear change in the governing failure mechanism of the structure occurs. This impact is positive since bending failure is a less brittle failure mechanism and is more predictable than shear failure. It is recommended to analyze more viaducts with similar characteristics in order to generalize the phenomenon of the change in the governing failure mechanism due to ageing of the concrete. For this purposes it is recommended to perform 2D non-linear finite element simulations with load distributions derived from 3D linear-elastic analyses.

L.F. Soto Prof.dr.ir J.C. Walraven (TU Delft), Ir. J.A. den Uijl (TU Delft), Dr.ir. M.A.N. Hendriks (TU Delft), Ir. G.G.A. Dieteren (TNO), Ir. L.J.M. Houben (TU Delft)

For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

26 | Master’s Theses October 2011

2

Structural Engineering

Fatigue damage in the orthotropic steel deck with respect to the trough-to-deck plate joint in between the crossbeams Since the first application of an orthotropic steel deck in bridges, engineers have shown their great interest by using it in movable bridges and in most of the long span bridges. In the past several decades, the traffic intensity and the wheel loads have increased considerably. Due to that, fatigue cracks have occurred and have been detected in the orthotropic steel deck bridges which suffer from high stress ranges. After the initiation phase in the welds, the cracks grow into other structural components. When the crack length exceeds a certain value it will threaten the safety of the structure. Most fatigue cracks have been observed in the trough-to-deck plate joint. This kind of crack may endanger the running safety of the traffic on the bridge and the integrity of the structure and may also lead to rust of the steel. Therefore, the research was carried out with respect to this joint. The first part of the research covers the study of fatigue cracks in the object joint by means of finite element modeling of a part of the orthotropic steel deck with assumptions based on the Eurocodes and Dutch national annexes (loads and classifications). It turns out that the thickness of the wearing course, the thickness of the trough web and the thickness of the deck plate play a significant role in determining the stress level in the object joint. Furthermore, the wheel-load print and the location of the wheel load can also influence the stress level in the object joint. In addition, the 3D model also provides the idea for the development of a simplified model for the fatigue damage with respect to the object joint.

Student: Thesis Committee:

Based on the 3D model, it turns out that the maximum transverse stress range occurs at the mid-span of the trough. With this precondition in mind, the simplified model consists of two levels. The bottom level indicates the mid-span cross section which is directly loaded by the wheel load. Therefore, the width of the cross section (in the longitudinal direction) depends on the length of the wheel print. Each trough web in the bottom level is supported by a vertical spring indicating the longitudinal bending stiffness of the deck. The top level represents the not directly loaded part. Approximately, the width of this level equals to half of the trough span minus the length of the wheel print. Furthermore, a horizontal support is added on the bottom flange of the trough in each level. These two levels are connected by a rigid link which ensures that both of them have the same vertical deflection. This 2D model results together with the adjustment factors show a satisfactory fit with the 3D model results. As a result, some suggestions are given for the new steel bridge design. An 18 mm thick deck plate with asphalt layer is suggested for fixed bridges in Dutch highways. A 22 mm thick deck plate without asphalt layer is suggested for movable bridges. The fatigue damage assessment also shows that the transverse location of the wheel load and the transverse spreading have a significant influence on the fatigue damage in the object joint. In order to prolonge the fatigue life of the steel bridge, a high detail classification could be applied.

J. Liao Prof.ir. A.C.W.M. Vrouwenvelder (TU Delft), Dr. M.H. Kolstein (TU Delft), Dr.ir. P.C.J. Hoogenboom (TU Delft), Ir. F.J. van Dooren (Rijkswaterstaat), Ir. L.J.M. Houben (TU Delft)

For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

27 | Master’s Theses October 2011

2

Structural Engineering

Automatic Buckling Checks on Stiffened Panels Based on Finite Element Results

In this thesis a post processing tool for finite element analysis was developed to perform buckling checks on stiffened steel panels. The tool can perform buckling checks on rectangular, orthogonal stiffened plates including different panel sizes and openings. The procedure is completely automatic and is consequently conducive to reduction of engineering time. The tool detects geometrical and material properties from a finite element model and determines design loads based on stress results of a finite element analysis. The approach is in accordance with guidelines from design codes and therefore results can be considered to be verified according to the design code in question. The tool has been adapted to the American Bureau of Shipping guide for buckling and ultimate strength assessment for offshore structures.

Student: Thesis Committee:

The tool is compared to the ABS plate buckling tool of the commercial software SDC Verifier. Results show that the developed tool does not need as fine finite element mesh as the ABS plate buckling tool of the SDC Verifier to predict accurate buckling factors. Furthermore for general cases up to 25% reduction of buckling factors can be obtained with the developed tool compared to the SDC Verifier. The graph shows an example of the comparison of buckling factors between the proposed method (SCM) and the commercial software (SDC).

O. Hillers Prof.ir. F.S.K. Bijlaard (TU Delft), Dr.ir. P.C.J. Hoogenboom (TU Delft), Ir. W. van den Bos (TU Delft), Ir. L.J.M. Houben (TU Delft)

For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

28 | Master’s Theses October 2011

2

Structural Engineering

Autogenous shrinkage of cementitious materials containing blast furnace slag

Introduction

Research

In the Netherlands blast furnace slag (BFS) cement is commonly used. Concretes with this type of cement are known for good durability properties. Mainly for durability reasons non-designed cracking of concrete is undesired. When material deformations are restrained, stresses are induced, possibly leading to cracking. Deformations in the early age are of most interest, with general properties of the concrete material still being developed. For the early age this is mainly caused by temperature and autogenous deformations due to cement hydration.

Problem definition Importance of autogenous shrinkage has been recognized for high performance concretes, having relatively low water to cement ratios. It is becoming known that autogenous shrinkage is higher for materials containing BFS. As of late striking results have been found for magnitudes of autogenous shrinkage for common normal strength concretes with water to binder ratios > 0.4.

The thesis gives an overview on the topic of autogenous shrinkage for normal strength concretes from practice, containing BFS. First, results from previous research have been verified, followed by an indication of practical relevance of the topic. Main focus is the investigation on the influence of different material constituents, by changing the proportions or type of material. Experiments are conducted on concrete and cement paste, the latter is shown in the picture. Magnitude of autogenous shrinkage is related to total shrinkage and compared to prediction models known in practice. Combined with results on general properties an indication is given for the possibility of cracking due to autogenous shrinkage.

Results Tests on concrete ran for 197 days and showed an ongoing shrinkage in time. From tests on cement pastes an expansion is found during the first days. Combination of both results estimates the magnitude of tensile stress inducing shrinkage. Development of shrinkage for cement paste with BFS shows to be substantially different from that of ordinary portland cement paste.

Conclusions and recommendations The type of cement seems to be the main factor influencing the magnitude of autogenous shrinkage. Measured total shrinkage relates well to the values from prediction models used in practice, but for the use of BFS cement (CEM III/B) subdivision into autogenous and drying shrinkage does quite differ. Autogenous shrinkage is found to be half of the total shrinkage. At 28 days the magnitude of autogenous shrinkage approximates the maximum strain at break. The main recommendation is to not neglect autogenous shrinkage when BFS cement is used, even for normal strength concretes commonly used in practice.

Student: Thesis Committee:

R.M. Mors Prof.dr.ir. K. van Breugel (TU Delft), Prof.ir. A.Q.C. van der Horst (TU Delft),

Ir. W.J. Bouwmeester-Van den Bos (TU Delft), Dr.ir. E.A.B. Koenders (TU Delft), Dr.ir. E. Schlangen (TU Delft), Ing. J. de Vries (Bouwdienst Rijkswaterstaat) For further information, please contact the section of Building Engineering tel. 015-2784578 Email: [email protected]

29 | Master’s Theses October 2011

30 | Master’s Theses October 2011

3. Civil Engineering theses

Hydraulic Engineering

3

Hydraulic Engineering

Morphological modeling of the Atrato river delta in Colombia

The Colombian government aims to establish a connection that bridges the Atlantic Ocean and the Pacific Ocean. The new connection will largely take place on the current Atrato River, which has not yet been upgraded for a more extensive use of navigation in the near future. A bottleneck in the river is the delta area. Without structural dredging activities the river is completely inaccessible. This study investigates the morphodynamics of a river mouth of the Atrato delta, in order to improve its accessibility to provide navigation in the future and to minimize the dredging activities. In short, the main objectives of this study are (1) to gain insights into the morphodynamics of the delta, (2) to develop a hydrodynamic model on an unstructured grid, (3) to develop a morphodynamic model on a structured grid and consequently (4) apply these models to investigate measures that aim to improve the accessibility of a river mouth. In this study an approach is used to model the hydrodynamics first at a large scale and subsequently modelling the morphodynamics at a more detailed level. A hydrodynamic model is set up with an unstructured grid, which appears to be a powerful tool to model a topographical complex area such as the Atrato delta. The hydrodynamic model gives insights into the hydrodynamics of the delta and is capable to create specific time-dependent boundary conditions for the more detailed morphodynamic model. This approach solves the problem of enormous backwater adaptation lengths, which are initiated by the tidal movement and a large amount of bifurcations. Subsequently, a model with a structured grid has been set up to simulate the morphology around a river mouth. The morphodynamic model is able to identify the major processes that cause sediment deposition. The key process appears to be the sudden spreading and deceleration of the riverine water when the river flows

Student: Thesis Committee:

into the Golfo de Urabá. As the result of the relative strength of the outflowing fresh water compared to the tidal power, the flow velocities are almost constantly located seawards. This explains the low sediment deposition rates in the river part of the delta. The enhanced flocculationin saline water results in a compact zone of sedimentation. This report discusses four possible measures that aim to improve the navigability in the delta and to minimize dredging activities. Modelsare set up to simulate their effects on the delta hydrodynamically as well as morphodynamically. The modelled measures are (1) a sand trap, (2) an artificial outlet channel, (3) sediment diversion channels and (4) the artificial extension of a river mouth. The model forecasts that none of the investigated measures will avoid dredging activities completely. A navigable artificial river mouth situated more upstream in the river even leads to closures of the current river mouths. Of the examined measures, the implementations of a sand trap and sediment diversion channels raise the most potential to reduce the sediment supply to the current river mouths, without deteriorating the navigability in other parts of the river. The artificial extension of a river mouth with breakwaters does not decrease the sediment supply towards the river mouths. However, the sediment deposition process takes place in deeper water, which minimizes the dredging maintenance for at least several years. The findings of this study should be regarded as the first step in the extension of knowledge on the morphodynamics of the Atrato delta. At this stage the models will help to understand the morphodynamics at the delta in more detail and hopefully encourage the collection of more valuable data. For that purpose a measuring and monitoring program is presented in this report.

S. Post Prof.dr.ir. H.J. De Vriend (TU Delft, Deltares), Dr. Ir. E. Mosselman (TU Delft, Deltares), Dr.ir. C.J. Sloff (TU Delft, Deltares), Ir. A.P. Geleynse (TU Delft, Deltares), Dr.ir. A.M. Talmon (TU Delft, Deltares), Drs. N. Geleynse (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

32 | Master’s Theses October 2011

3

Hydraulic Engineering

Navigability at an unstable bifurcation The Montaño - Murindó bifurcation of the Atrato River in Colombia

The Atrato River in Colombia should be navigable for bigger vessels when generating a corridor which should link the Atlantic Ocean with the Pacific Ocean. A likely segment of the river that forms a critical point for navigation is the point of bifurcation where the river is divided in the Montaño and Murindó branch. Both branches should be reasonably navigable, but bifurcation morphodynamics possibly render the water depth in one branch smaller than the draught of the vessel. It is noted that the Montaño branch is considered the main corridor, as this branch is shorter and generally wider. The main objective is to model and understand the morphology that evolves around the river bifurcation and discuss possible measures for creating a sustainable navigable channel. In order to create insights in these morphodynamics, a computational model has been set up. Using the software package Delft3D, a 2DH morphodynamic model of the area around the bifurcation has been made. Due to the lack of sufficient data available, a thorough morphodynamic calibration and verification is impossible. It was shown that the model predicts a development to a stable, but often highly asymmetrical discharge division. The model attains this equilibrium after 50 years of morphological modelling. This suggests the bifurcation is unstable. The evolution to an asymmetrical discharge division is mainly governed by the imposed downstream boundary water levels because a head difference over the branches determines the division of flow over the branches. The calibrated model assumes no backwater effects, which means that the shorter Montaño branch (83 km) has a larger water level gradient than the Murindó branch (91.5 km). It was shown that the unknown head difference over the branches greatly influences the global development of the branches (i.e. aggradation /degradation). Because only one bathymetrical survey was executed, erosion and sedimentation rates are unknown, which further decreases the possibility of accurately modelling the area.

Student: Thesis Committee:

An important result is that when imposing the same water level gradients in both branches, the model still predicts a development to a highly asymmetrical division of flow discharge (i.e. 75% through the Montaño branch). This means that local geometrical phenomena influence the division of flow and sediments. The sharp angle of offtake of the Murindó branch results in flow separation which in turn causes a sediment trap at the entrance of this branch. As a result, the cross-section reduces significantly, which means less discharge is directed through this branch. Another phenomenon is caused by the present river bend just upstream of the point of bifurcation. This leads to a gravitational pull along the transverse slope which initially leads to an increasing bed load transport through the Murindó branch. Another local phenomenon is the Bulle effect which leads more bed load through the Murindó branch due to the river bend formed by the upstream bend and the offtaking channel. Discussing possible solutions is sometimes hypothetical as the global evolution is sensitive to the unknown downstream boundaries. The possibility of two different bend cut-offs are discussed. It was shown that the angle of offtake greatly influences the division of flow discharge and sediments. Decreasing the offtake-angle of the Murindó branch from 90° to 30° means the Murindó branch gets dominant (60% flow discharge through this branch instead of 20%). As the internal connection between the branches can result in significant backwater effects, it can be a simple solution to cut off this connection. In conclusion, the present available data prove to be insufficient. Measuring stage and discharges in both branches, river bed profiles and sediment characteristics can indicate which branch will be dominant and enable future decision making.

F.C.R. Melman Prof.dr.ir. H.J. De Vriend (TU Delft, Deltares), Dr.ir. E. Mosselman (TU Delft, Deltares), Dr.ir. C.J. Sloff (TU Delft, Deltares), Dr.ir. A.M. Talmon (TU Delft, Deltares)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

33 | Master’s Theses October 2011

3

Hydraulic Engineering

On the morphodynamics of Lagos Harbour An exploratory study of the tidal system

The city of Lagos, Nigeria is the nation’s largest city and acts as an economical hub for the region. Lagos Harbour plays an important role in supplying the region with the logistic needs of the metropolitan area. As the population reaches over 15 million people and economic welfare increases, the need for imported goods is ever growing. The recent past shows a trend in more and increasingly larger vessels calling the port. As the ships become larger, the required navigational depth increases as well. Currently, two small hopper dredging vessel carry out maintenance dredging operations in the main channels of Lagos Harbour: Commodore channel, Apapa channel and Badagry creek. Especially for Badagry creek holds that the navigation channel is difficult to maintain at the desired depth. Experiences from the local sailors and port authority shows the problem is that there seems to be a large amount of fine material being supplied to Badagry creek and that dredging efforts are ineffective. Laboratory tests confirm that a large amount of poorly flocculated montmorillonite clay is present. This material has a very low settling velocity and may be transported as a fluid mud layer. The fine material causes the ships to become stuck in a muddy bed after spending time at a quay. As the settling velocity is very low, little dredged material will remain in the hopper’s hold and overflow losses are significant. Based on the soil samples and bathymetric charts, it can be concluded that this is not the case for Commodore and Apapa channel. A layer of soft mud was encountered in Badagry creek and the Lagoon. Analysis of the material found that it has a low settling velocity and has a low zeta-potential which is not susceptible to changes in acidity. These are properties typical to montmorillonite clay and the hypothesis may therefore be justified. As the flow velocities in the main channels of Lagos Harbour are high, the material does not settle in the main navigation channels. It is therefore assumed that although fine sediments may cause problem to shipping in Badagry creek, this material does not affect the navigational depth of Commodore and Apapa channel. Here only sand is found on the bed.

Student: Thesis Committee:

Measurements of the salinity and flow direction/ velocity profiles in Commodore channel and Badagry creek show stratification of currents which are most noticeable during the turning of the tidal flow towards flood. Stratification of currents or salinity has not been observed in Apapa channel. The density current has a strong effect on the sediment transport rates near the bed of Commodore channel and Badagry creek. Here, the net transport during an ebb/flood cycle is positive in the flood direction while higher in the water column and in Apapa channel, net ebb directed transport occurs. It is assumed that the discharge of rain water is responsible for the stratification in salinity and therefore the flood directed transport near the bed. The added discharge of rain water also causes the flow velocity during ebb to increase and thus sediment transport, especially higher in the water column. It may be worthwhile to set-up a 3-dimensional morphodynamic model of the system to join the separate data sources and get a better understanding of the processes in the system, for instance, at the junction of the major channels. The current dredging strategy with TSHD dredgers has proven inefficient for maintaining the navigation channel in Badagry creek due to the fine sediments found there. A promising technique for this problem is to use water injection instead. The effectiveness should be researched as well as negative side effects to other parts of Lagos Harbour before implementing such a dredging strategy.

V. Ballendux Prof.dr.ir. M.J.F. Stive (TU Delft), Dr. ir. J.C. Winterwerp (TU Delft, Deltares), M.J.J. Reneerkens MSc (Royal Haskoning), Dr. Ir. B.C. van Prooijen (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

34 | Master’s Theses October 2011

3

Hydraulic Engineering

Tidal divides A simplified case and the Dutch Wadden Sea

In this thesis the position of tidal divides is studied by means of a simplified model and the Dutch Wadden Sea.

Position of tidal divide To study the parameters influencing the location of the tidal divide, two basins are schematized to a rectangular channel with at each side an incoming tidal wave. These two incoming waves can differ in amplitude and have phase difference. The tidal divide is shifted towards the channel end with the largest wave amplitude or the end where the wave enters last. If the phase difference and/or wave amplitude ratio between the two incoming waves is too large, there is no tidal divide at all. It turned out that a distinction between two cases can be made: a linear case with very low wave amplitudes and flow velocities, in which the bottom friction is neglected; and a nonlinear case with higher wave amplitudes and velocities resulting in a dominant role of the bottom friction. The limit of the phase difference for the Wadden Sea means that the barrier islands should have a certain length and/or that the basin should be relatively shallow. In the linear case, the difference in amplitude between the two waves is most important in determining the location of the tidal divide. The contribution of the phase difference is minimal. When bottom friction becomes dominant, the phase difference is governing the position of the tidal divide and the influence of the amplitude ratio is very small. The depth of the channel is an important parameter, because it influences the importance of the bottom friction. In the Wadden Sea, both the phase difference and the difference in tidal range in the inlets is contributing to an eastward location of the tidal divides.

Student: Thesis Committee:

Definition tidal divide A distinction is made between a hydraulic tidal divide and a morphological tidal divide. A hydraulic tidal divide is the line splitting the basins in terms of drainage and can be defined as the position where the standard deviation has a minimum. Engineers are looking for a clear line, because then the hydraulic tidal divide can be used as a basin boundary. In reality there is no line, which makes it difficult and arbitrarily to define a line. This has to be kept in mind when analyzing hydraulic tidal divides. In the Wadden Sea, the morphological tidal divide has the shape of a spine. The centre line of this spine does not necessarily coincide with the highest bed level. The morphological tidal divide is the footprint of the hydraulic tidal divide on the bed and indicates where the hydraulic tidal divide is or has been. The height of the morphological tidal divide can tell something about the equilibrium of the basins.

Movement tidal divides The hydraulic and morphological tidal divide can move due to changing circumstances, like closure of a part of the basin. The hydraulic tidal divide can move instantaneously, but its shift is bounded by the morphological tidal divide. The morphological tidal divide first has to be lowered by increased flow velocities and then the hydraulic tidal divide can move more freely. The morphological tidal divide then heightens again at the new location of the hydraulic tidal divide. This behaviour is illustrated by the tidal divide between Marsdiep and Vlie and shows the importance of the initial bathymetry for the evolution of tidal divides. If the circumstances change more gradually, as happens in the eastern Wadden Sea, the morphological can keep up with the movement of the hydraulic tidal divide more easily.

J. Vroom Prof.dr.ir. M.J.F. Stive (TU Delft), Ir. M.H.P. Jansen (Witteveen+Bos), Dr.ir. R.J. Labeur (TU Delft), Dr.ir. B.C. van Prooijen (TU Delft), Dr.ir. Z.B. Wang (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

35 | Master’s Theses October 2011

3

Hydraulic Engineering

Risk-based control of salt water intrusion for the Rhine-Meuse Estuary

Abstract The fresh water supply will be more under pressure, due to the predicted effects of climate change in the Netherlands. More frequent salt water intrusion during the summer semester is caused by the joint occurrence of low river discharges and the expected sea level rise. The control of external salinity is necessary to guarantee a sufficient water quality of the main water system and so protect the fresh water inlets from the intruding saline water. Consequently, regional water systems are able to take in fresh water of the main water system to control internal salinity, through counteracting salt seepage by means of salt flushing. The control of external salinity can be realized by the implementation of measures that interfere in the main water system; e.g. by optimizing the fresh water distribution. Whether a measure will be implemented depends on the decision-making process. This study is initiated, because of the arisen discussions about the pursued fresh water policy for the drought in 2003. Salinity risk management aims to assess the costeffectiveness of measures that focus on the fresh water supply, by means of evaluating the costs and the benefits of a measure. This study investigates the possibilities of the implementation of a risk-based approach within the present Dutch fresh water policy, which is nowadays based on a deterministic approach.

A salinity risk management model is developed that basically is composed of three phases that research the following questions; i.e. 1.) How does the system of external salt water intrusion in the Rhine-Meuse Estuary function for given scenarios? 2.) What is the frequency of occurrence of external salinity? Given that external salinity occurs, what are the consequences? What is the resulting salinity risk? 3.) Is the established risk acceptable? If not, which alternative measures are able to reduce the present risk level? The developed research model is examined in a case study for the risk evaluation of external salt water intrusion in the Hollandse IJssel, in particular the fresh water inlet of Gouda that provides fresh water to the control area of Rijnland. This study concludes that a risk-based approach is implementable in the Dutch fresh water policy, but extended research is necessary to obtain more reliable exceedance frequencies of a Chloride concentration. This study developed two probabilistic models; i.e. for tidedominated locations and for river-dominated locations. A third type probabilistic model should be developed for locations that are not tide- or river-dominated. Secondly, more precise statistical analysis should be conducted after the discharge variation in course of time for low river discharges. Besides, statistical research is recommended after the variation of the probability distributions thorough the summer semester of low river discharges, high sea water level set-ups and a precipitation deficit.

Student: M. Zethof Thesis committee: Prof.dr.ir. M.J.F. Stive

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

36 | Master’s Theses October 2011

3

Hydraulic Engineering

Modelling Sediment Transport in the Swash Zone

The swash zone is the part of the beach that reaches from the limit of wave run-up until the limit of wave rundown. It is recognized as being a dynamic area of the nearshore region, characterized by strong and unsteady flows, high turbulence levels, large sediment transport rates and morphological changes on a small timescale. Due to the complexity of the processes taking place in the swash zone, there are still great uncertainties about the driving forces for sediment transport. Morphodynamic process-based numerical models tend to overestimate the seaward directed sediment transport in the swash zone, especially for mild wave conditions. The main objective of this thesis was to obtain insight in the hydrodynamic processes responsible for sediment transport in the swash zone, and to use this knowledge to optimize a morphodynamic numerical model (XBeach) for simulating swash zone physics.

Numerous research experiments have been conducted over the past fifteen years, both in laboratory and in the field. The results of the literature review carried out in this thesis show that wave asymmetry, wave skewness, turbulence and boundary layer effects are important processes considering sediment transport in the swash zone. Infiltration, exfiltration and groundwater flow are found to be dominant on steeper beaches with larger grain sizes. Swash-swash interactions, acceleration and horizontal pressure gradients are generally found to be important in the swash zone, but are, however, not well understood yet.

Student: Thesis Committee:

To obtain insight in the simulated swash characteristics for different beach state levels (quantified by the Iribarren number), linear profile simulations were conducted with a typical wave steepness and beach slope combination. The main results of these simulations show that the beach state level has a great effect on the predicted hydrodynamics and morphodynamics. Next, three hydrodynamic modelling approaches are studied (surf beat approach, hydrostatic approach and non-hydrostatic approach), in which the swash hydrodynamics are simulated in more or less detail, and two different sediment transport models (Van Rijn [2007] transport model and Nielsen [1992] / Roelvink & Stive [1989] transport model). All approaches are verified with a dataset obtained from a field experiment in Le Truc Vert, France. The results show that the hydrostatic approach in combination with the Nielsen / Roelvink & Stive transport model provides a good prediction of the measured morphodynamics. There is, however, an underestimation in the predicted run-up observed. It is considered most likely, that the underestimation is due to two-dimensional effects (e.g. wind), that are not accounted for in the one dimensional simulations.

A. van Rooijen Prof.dr.ir. M.J.F. Stive (TU Delft), Prof.dr.ir. A.J.H.M. Reniers (University of Miami), Dr.ir. J.S.M. van Thiel de Vries (TU Delft, Deltares), Ir. R.T. McCall (Deltares, University of Plymouth), Ir. M. Henriquez (TU Delft), Ir. P.B. Smit (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

37 | Master’s Theses October 2011

3

Hydraulic Engineering

Dune erosion near sea walls XBeach validation

Storm impact on a dune-dike system During a storm dunes erode and provide sediment to the beach. The foreshore rises and the wave height decreases. Subsequently the wave-induced water level setup increases. Seawalls do not erode. The waves in front of the seawall remain high throughout the storm and the wave-induced water level setup hardly changes. Over a dune-dike connection a water level gradient drives a current which transports sediment from the dunes to the seabed in front of the seawall. The loss of sediment to the dike causes the foreshore of dunes near the connection to rise slower resulting in more erosion. Obliquely incident waves generate a longshore current which transports sediment along the shore. In front of a seawall the velocity and transport capacity of the longshore current is limited. In a dune transect the the transport capacity of the longshore current is larger. Subsequently there is a longshore gradient in the transport capacity in the transition zone. The amount of additional erosion near structures depends on the angle of wave incidence w.r.t. the shore. Dunes situated downstream of the connection experience a significant increases in erosion. Near the upstream connection sediment is deposited on the seabed in front of the structure. Sediment will pile up against the structure resulting in less erosion near the connection.

Model-data comparison The measurements of the experiments are compared with XBeach predictions. In XBeach the erosion in a dike breach is a function of the breach width and the wave period. The erosion increases for a smaller breach width. The breach erosion increases for an increasing wave period. XBeach underestimates the erosion above the dune revetment. To erode the dunes above the revetment wave runup is an important process. Currently XBeach only simulates long wave runup. The erosion in the revetment breach is predicted well. For experiments V1 & V3 with a wave period of Tp = 2.07 seconds the predictive capabilities of XBeach in dune sections are very good. The performance of XBeach for experiments V2 & V4 with Tp = 1.55 seconds is relatively good. The peak frequency has a relatively large influence on the amount of dune erosion predicted by XBeach. The effect of the wave period for 2DH models with a large depth scale (nd = 60) is not properly simulated by XBeach.

Experiments in the Delta Basin The influence of structures on dune erosion was investigated in a series of experiments. They were carried out with normally incident long-crested waves and were aimed at 4 different connections between a dune and a structure. Two configurations of dunes and structures were investigated. Each configuration was tested with 2 different wave periods Tp. The experiments proved the development of additional erosion near structures. The connections investigated in the experiments were: 1. The connection between a dike and an unprotected dune, 2. The connection between a dike and a dune that is protected by a dune revetment, 3. A breach in a dike with a body of sand, 4. A breach in a dune revetment.

Student: Thesis Committee:

B. de vries Prof.dr.ir. M.J.F. Stive (TU Delft), Dr.ir. J.S.M. van Thiel de Vries (TU Delft, Deltares), Dr.ir. A.R. van Dongeren (Deltares), Ir. P.F.C. van Geer (Deltares), Ir. P.B. Smit (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

38 | Master’s Theses October 2011

3

Hydraulic Engineering

System description Noord-Holland coast, a review of the nourishment strategy applied.

The safety of a large part of the Netherlands is dependent on the safety level of our flood protections. In the last centuries, structural erosion of the coastline and the increase of the use of the hinterland have made coastal maintenance a necessity in order to provide this safety. The Noord-Holland coast is one of the most extensively maintained coastal stretches of the Netherlands. In the last twenty years Rijkswaterstaat nourished this coastal stretch with a total volume of 44 million cubic meters, in the shape of beach and foreshore nourishments. To assess the need of such extensive maintenance and to map sedimentation and erosion trends a system description is made. For this analysis, the JARKUS database is used. This allowed to study the near shore zone over the last forty five years. In the year 1990 a new coastal maintenance policy was introduced; “Dynamic Preservation”. This policy had the strategic objective “to guarantee a sustainable safety level and sustainable preservation of values and functions in the dune area” (Min V&W 2001). To reach the objective a coastal state indicator has been implemented. Since the implementation of this benchmarking principle and the “Dynamic Preservation” policy the nourishment volume increased vastly.

Student: Thesis Committee:

The near shore volume corrected for nourishments over the period 1990 – 2010 shows an autonomous degradation of similar order compared to the years 1970 – 1990. This indicates that for the whole NoordHolland coastal stretch, the concept of the autonomous behaviour as conservative indication of erosion / sedimentation rates holds plausible values. The system description indicates that the coastal stretch of NoordHolland received a significant larger nourishment volume than deemed necessary to reach the objective of the “Dynamic Preservation” policy. Alongshore transport rates over the + 3 to – 8 m zone put forward by Stive and Eysink (1989) as well as by Van Rijn (1997) together with the aforementioned sedimentation / erosion rates alowed to generate a sand budget model. Averaged erosion / sedimentation rates and longshore transport rates are quite consistent over the period 1965-2010. Although the sand budget model holds some quite limitations, the result can be considdered to be quite acceptable.

R. Pot Prof.dr.ir. M.J.F. Stive (TU Delft), Dr. R. Spanhoff (TU Delft), Drs. Q.J. Lodder (TU Delft), Ir. D.J.R. Walstra (TU Delft), Dr.ir. N. Geleynse (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

39 | Master’s Theses October 2011

3

Hydraulic Engineering

Modelling decadal barrier island behavior

Barrier island behavior Barrier islands can undergo tremendous morphological changes, especially during extreme weather events, such as hurricanes. Such an extreme weather event is usually followed by a meteorological calm time period. A barrier island tends to recover from the severe impact of the (short-term) extreme event during this period. This recovery process requires a significant onshore sediment transport, which can be achieved by waves and wind (Aeolian transport). The transported sediment can be trapped by vegetation and eventually create dunes. In this thesis the long-term behavior of barrier islands is investigated and therefore both the impact events and the recovery events need to be taken into account.

Model train The (short-term) extreme weather events and the meteorological calm time period mentioned above are both captured in a newly developed model train, which is used to investigate the long-term behavior of barrier islands. The extreme weather events in this model train are modeled with a 2DH process based model, named XBeach. The meteorological calm time period in between the events are modeled with a newly developed recovery model written in MATLAB. The output of XBeach functions as input for the recovery model and vica versa. The result of coupling of the two models is a 1D model train which makes it possible to repeat the erosion- and recovery phase successively (see figure).

Student: Thesis Committee:

Figure 1: Model train schematization

Validation Data from the Chandeleur Islands is used for the validation of the model train. The validation of the model train simulations show that the model train is capable of modelling the behavior of the island qualitatively. The validation runs also show that the morphological evolution of the Chandeleur Islands for the period 2002 – 2010 is mainly influenced by three short-term extreme events. These events are hurricane Ivan, hurricane Katrina and hurricane Gustav. Especially hurricane Ivan caused a tremendous morphological change. This hurricane caused a reduction of the maximum elevation of about 1.5 meter in the modeled period. Although the influence of the short-term extreme weather events on the long-term (decadal) morphological behavior of barrier islands is high, the recovery phases in between these impact events have an important role as well.

K.W. Pruis Prof.dr.ir. M. Stive (TU Delft), Dr. J.S.M. van Thiel de Vries (Deltares, TU Delft), Ir. R. McCall (Deltares), Dr. J.E.A. Storms (TU Delft), Ir. S. de Vries (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

40 | Master’s Theses October 2011

3

Hydraulic Engineering

Notional Permeability of breakwaters “Experimental research on the permeability factor P”

Stability of rock slopes

Tested structures

Different layer design of a rock slope and under layers has a large effect on the strengths on the rock slope itself. In the stability formula developed of VAN DER MEER [1988] this effect is represented by the term Notional Permeability with symbol P. A more open, or permeable, structure underneath the armour layer has the ability to dissipate more wave energy and therefore requires less weight of the armour layer. The influence of this parameter is thus very important in economic sense. Up until now only three configurations have been tested. In practice often intermediate structures were designed which do not correspond to the standard situations. P-values have then to be estimated in comparison with the known structures, which gives some uncertainty around the P-value. Therefore there is the demand for more validated values of the notional permeability representing other structures. This is especially relevant because small variations in P may result in large variations in required stone weight (and consequently in layer thickness).Producing more values for the notional permeability can be done in two ways. It can be done with means of a theoretical model or numerical model, or by determining it empirically using scale model tests. Within this study the second method, determining the value empirically by physical model tests is used.

First of all two reference structures were tested to ensure that the test method and the method of analysis resulted into the same value for the notional permeability as defined by Van der Meer. The first structure was a structure with a permeable core, which according to Van der Meer has a value of P=0.5. After analysis of the tests executed within this study a value of P=0.55 was found. The second structure had an impermeable core and therefore a very low permeability. According to Van der Meer the value of the notional permeability is 0.1. After the tests a value of P=0.08 was found. Overall the conclusion was drawn that the method of testing and analysis resulted in similar outcomes as the research of Van der Meer in 1988. Therefore it is validated to draw conclusions from similar tests on new structures.This new structure consisted out of an impermeable core, covered by a thick filter layer with a relatively small stone size, followed by a coarse filter layer and finally an armour layer, see Fig. 1. This structure represents the real life situation in which a core of sand is placed and covered by a geo-textile. Then quarry run is used to create the desired slope of the structure and the coarser filter layer is used to make the filter geometrically closed. Finally, like all the other structures, the double armour layer is used to withstand the wave impact.

Conclusion After conducting all the tests on the 1:2 slope the analysis showed a value for the notional permeability of P=0.37. Because only a limited number of tests on only one slope angle have been conducted it is advised to use the value of P=0.35 for design practice, until further data is available.

Student: Thesis Committee:

R. Kik Prof.dr.ir. M.J.F. Stive (TU Delft), Prof.dr.ir. W.S.J. Uijttewaal (TU Delft), Ir. H.J. Verhagen (TU Delft), Ir. J.P. van den Bos (Royal Boskalis Westminster / TU Delft), Dr.ir. J.W. van der Meer (Van der Meer consulting), Ir. J. Maertens (DEME)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

41 | Master’s Theses October 2011

3

Hydraulic Engineering

Earthquake analysis of quay walls

In this thesis the impact of an earthquake on quay walls located at the Euromax terminal of the Port of Rotterdam is analyzed. A quay wall is a soil retaining structure where ships can moore and transfer goods. Seismic behaviour of two different types of quay walls are investigated and compared by performing a seismic analysis on the Euromax terminal. The first quay wall is the existing quay wall of the Euromax terminal which is a diaphragm quay wall with relieving structure and the second quay wall is a caisson quay wall. The seismic analysis is based on three steps which will include assessment of the regional seismicity, the geologic hazards and soil-structure interaction analysis. The first step is to define the earthquake motion and its magnitude for the Euromax terminal. This is done by making a seismic hazard analysis which is based on geologic, tectonic and historical seismicity data available for the Netherlands. The probability of occurrence of a high earthquake magnitude at the Euromax terminal is very low due to the fact that no major faults are located near the terminal. The second step is to define the dynamic soil response of the Euromax terminal. This is accomplished by making a liquefaction analysis to determine the liquefaction resistance of the near surface soils and the associated potential for ground failure. Loose soils are much more susceptible to liquefaction than dense soils. The soil deposit at the eastern side of the terminal consists of several layers of loose sand which made this the most sensitive section to liquefaction. Liquefaction at this location occurs at earthquake magnitude of M L = 6,2 which corresponds with a horizontal peak ground acceleration of aH = 3 m/s2 and a return period of 751000 years.

Student: Thesis Committee:

The final step is to make a seismic analysis of the quay wall structure including seismic forces acting on the two different quay walls. A literature study shows that once an earthquake hits the Euromax terminal causing the ground to shake may result in three major disadvantageous consequences for a quay wall structure. First the driving forces acting on the quay wall will increase. Secondly, shear resistance may decrease due to excess pore water generation resulting in softening of the soil and resonance may develop when the earthquake frequency reaches the fundamental frequency of the structure. The three consequences may result in strength, stability and displacement failure of a quay wall structure. Over all it can be concluded that the probability of occurrence of high magnitude earthquakes are very low. When an earthquake does strike the Euromax terminal the diaphragm quay walls and a caisson quay walls fail in a different way. It appeared that the critical failure mechanism of the diaphragm quay wall is caused by the insufficient bending capacity of the diaphragm wall resulting in breaking of the diaphragm wall. For the caisson quay wall the critical situation relates to large deformations of the landside crane track causing the cranes not to function properly. Nevertheless, both failure mechanisms occur at the same order of earthquake magnitude ML ≈ 5,1 which corresponds to a return period of approximate 2500 years. This indicates that both quay walls have the same order of resistance against earthquake. However, the consequences of the diaphragm quay wall failure and probably also for the combined walls will be much higher compared to that of the caisson. For this reason, the caisson quay wall is a better solution against earthquakes compared to the diaphragm wall.

J.W. Liang Prof.drs.ir. J.K. Vrijling (TU Delft), Prof.ir. A.C.W.M. Vrouwenvelder (TU Delft), Dr.ir. J.G. de Gijt (TU Delft, Public Works Rotterdam), Ir. W.J.M. Peperkamp (TU Delft), Ir. A.A. Roubos (Public Works Rotterdam)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

42 | Master’s Theses October 2011

3

Hydraulic Engineering

Preparing a long term management plan for the future of the Slufter An analysis of the functional, spatial and geotechnical possibilities Summary The Slufter is a large scale disposal facility for contaminated dredged material from the Dutch rivers, channels and harbour basins. It is located in the Rotterdam harbour, on the south-western tip of the Maasvlakte. Since the Slufter was built in 1987, the supply of contaminated dredged material has decreased significantly. As a result, the prognosis is that it will take a long time before its full capacity of 150 million cubic meters is utilized. At the moment, approximately 50% of the basin has been filled.

The overcapacity and surplus of space raises questions on the applicability of this area for purposes other than storage of dredged material. In this research, preparations are made for the establishment of a long term management plan by analyzing the functional, spatial and geotechnical possibilities of the Slufter. The aim has been to find potential future functions and ways to create land in the Slufter. For the short term the best opportunities for future functions can be seen for renewable energy projects, such as solar panels, windmills and algae breeding. In addition, the opportunities for a nature and/or birds reserve are clearly present. For the long term, after complete dismantlement of the Slufter as a disposal facility, harbour related functions such as empty depot or

Student: Thesis Committee:

storage of chemicals provide the best options. In the spatial and geotechnical analysis two alternatives for creating land have been considered; the first alternative analyzes the feasibility of a retaining structure, and the second alternative focuses on the natural process of ripening clay. The purpose of a retaining structure is to provide a physical boundary between the storage basin and the new function(s). The geotechnical feasibility of a retaining structure built on top of the 30m thick layer of dredged material, in the shape of an embankment, has been proven. However, the embankment would require large dimensions and thereby large quantities of construction material, and thus a large investment. Moreover, the large dimensions limit the amount of surface area that can be obtained. It is therefore recommended to further investigate techniques that make it possible to realize an embankment with steeper slopes. A more cost effective solution is the clay ripening alternative. Here, a long term approach is recommended. In this approach the incoming supply of contaminated dredged material is used as the elevation material. Once a layer of ripened dredged material with sufficient thickness has formed, enough bearing capacity can be guaranteed for further development. This approach combines short term opportunities for the application of small scale functions with a long term, sustainable solution towards an early dismantlement of the Slufter. In addition, this approach if permanent implicates that the high surrounding dike structure of the Slufter is no longer needed and can therefore be (partly) removed. The obtained space can then also be used for other purposes. A decision making tool has been developed to give the Port Authority an overview of the short and long term possibilities, and to serve as a guideline for selecting an alternative approach on storage handling and use of space.

R. Heerema Prof.ir. Tiedo Vellinga (TU Delft, Port of Rotterdam), Prof.ir. Frits van Tol (TU Delft, Deltares), Dr.ir. Jarit de Gijt (TU Delft, Gemeentewerken Rotterdam), Ir. Gijs Berger (Port of Rotterdam)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

43 | Master’s Theses October 2011

3

Hydraulic Engineering

The behaviour of a moored oil tanker in the Port of Leixões, Portugal. With use of numerical models. The Port of Leixões is located in the north of Portugal. The operational conditions at berth “A” are affected by several factors resulting in a down-time of the berth of about 20%. In order to describe the behaviour of the moored vessel physical model tests were performed at the Faculty of Engineering University of Porto within the research and development program DOLPHIN. Numerical simulations of wave propagation including non-linear wave interaction and the generation of both sub- and super-harmonics were not carried out in the DOLPHIN program. Within this study a sequence of numerical models was applied to describe the moored ship motions and make a comparison with measurements from the physical model tests. An approach which combined a Boussinesq-type wave model with a panel model was selected as the appropriate approach for the present study. A Boussinesq-type wave model was selected, since diffraction around a breakwater, partial reflection from port structures and non-linear wave processes are important and relevant hydrodynamic processes to describe the wave field in the vicinity of the ship. The output from the Boussinesq-type wave model describes the surface elevations as well as the velocity field of the waves in the vicinity of the ship. The successive panel model takes the presence of the ship within the incident wave field into account and calculates the wave forces on the ship. The calculated total wave forces are a summation of the Froude-Krylov, diffraction and second order wave forces. Time-series of wave forces serve as an input for a ship simulation model, which simulates the ship motions and the mooring forces, taking into account environmental forces and non-linear interactions with the mooring system. The initial approach combined the Boussinesq-type wave model MIKE21 BW, with the panel model Harberth and the ship simulation model Quaysim. Due to numerical instabilities within MIKE21 BW an eddy with unreliable velocities was formed after longer period of simulation. This eddy was located in the vicinity of the ship. The subsequent computations with Harberth resulted in a continuous increase in second order wave forces on the ship. The first order wave forces on the ship did not

increase continuously, but via an analysis it is shown that the calculated first order wave forces on the ship are not reliable. The finally simulated ship motions in Quaysim are not reliable as well. The unreliable wave forces on the ship as well as the unreliable subsquent simulated ship motions are a consequence of the pre-simulated instabilities within MIKE21 BW. The cause of the numerical instabilities in MIKE21 BW could not be discovered during this study. Since longer period of simulations are required to obtain statistical reliable ship motions a switch was made to an alternative Boussinesq-type wave model called TRITON. Adaptations in the model set-up in TRITON ensured that numerical instabilities over longer periods of simulation in the simulated velocity field were avoided/minimized. The emphasis in simulations with TRITON is on simulating and understanding the low frequency waves. The focus was on simulating the low frequency waves that caused significant moored ship responses within the physical model. The simulated waves in TRITON agree well with the measured waves in the physical model basin. It is shown that a standing wave is measured in the physical model basin, which caused measured surge responses of the ship. The obtained insight in the generation of these low frequency waves may be used when performing additional physical and/or numerical model tests. It is recommended to simulate the total Port of Leixões with a Boussinesq-type wave model, taking into account all relevant hydrodynamic processes for moored vessel response. In that case a bound long wave should already be imposed in the incoming generated waves, since the generation of primary waves only may lead to an underestimation of the total content of low frequency waves. The wave simulations, as performed with TRITON, are expected to be sufficiently accurate to serve as an input for vessel response computations. The recommended additional wave simulations and vessel response computations are expected to provide additional insight in the causes of excessive ship motions. New insight in the behaviour of waves as well as vessel response may lead to improvements of the operational conditions at berth “A” in the Port of Leixões.

Student: M. van der Wel Thesis Committee: Prof.ir. H. Ligteringen For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

44 | Master’s Theses October 2011

3

Hydraulic Engineering

Interaction between loaded barges and bed material

Shallow sections in the river Waal lead to a hindrance for the users and for high maintenance costs for the administrator, Rijkswaterstaat. Dredging these small shoals is inefficient and takes time in which the users can not sail with full draught. Sailing with a limited amount of cargo leads to reduced income and users of the river Waal try to keep sailing with maximum draught. It is known that ships in restricted waterways cause sediment transport which sometimes leads to erosion. Part of this erosion is due to propeller induced flow velocities, the other part is caused by increased flow velocities called return flow. Return flow is depending on draught, dimensions of ship and waterway, sailing speed and flow velocities in the river itself. Goal of this master thesis is to investigate the influence of the parameters influencing return flow and investigate the caused erosion by changing those parameters in model studies and flume experiments. From these experiments it becomes clear that flow velocities significantly increase with a decreasing under keel clearance. From measurements it follows that the flow velocity under the bow of the barge increases with maximum of 1.31 times the return flow velocity as calculated using Schijf (1949). From computational model runs and experiment done in a flume at Deltares it follows that only 55% of specific discharge is left under the bow. 45% is considered to be diverged to the sides of the barge; this process is called fanning out. Besides the model tests, two cases are taken into account: the standard operating speed (2.56m/s) of a push barge combination sailing in upstream direction and the same push barge combination but now sailing with its maximum speed possible. This maximum sailing speed (3.07m/s) is calculated regarding the installed power of a push boat and the resistance a push barge combination will encounter when sailing with a certain speed and draught. Ship squat is calculated using Ankidunov and Schijf, these values are compared with measured values of sinkage of the barge during the experiments. Ankidunov gives higher values for the amount of squat then Schijf. Differences for the two considered sailing speeds is 0.10m for both cases. It is shown that measured values are comparable with the calculated values. It

Student: Thesis Committee:

is important to predict the amount of squat to prevent accidents. A ship sailing with a speed of 2.56m/s in upstream direction will have a squat of 0.42m (10% of the original draught of 4m). With a speed of 3.07m/s, the amount of squat increases to 0.60m. Although bed levels were measured in an accurate way, the measuring error combined with a relative high grain size leaded to unreliable data about bed level changes. Focus of the research was therefore moved to the velocity profile and defining a simple model which is able to calculate occurring flow velocities under a ship’s bow. Results from this model are compared with measurements and existing formulae. Data gained from measurements of DelKelv show a correlation with the maximum measured flow velocities under the bow of the barge. No correlation is found with the average measured flow velocities. Since most of the existing formulae are focused on the maximum occurring flow velocities, this lack of correlation between average flow velocities and modeled flow velocities does not matter. From the different flow velocities gained from calculations, measurements and model runs, it becomes clear that the modified Martin and Maynord equation and the WL DelftHydraulics formulae predict the maximum occurring flow velocities very well. Finally the occurring flow velocities are used as input for a sediment formula (Engelund-Hansen) and for the two considered cases the effect on the amount of sediment transport is investigated. From this it becomes clear that although the flow velocities increase significantly due to the passage of a push barge combination, the time over which this increase takes place is not long enough to induce serious sediment transport. Using push barge combinations for the removal of small sandy shoals in the river Waal does not seem to be very effective.

R. J. Lenselink Prof.ir. T. Vellinga (TU Delft), Dr.ir. H. J. de Koning Gans (TU Delft), Dr.ir. A. Sieben, (Rijkswaterstaat Waterdienst), Ir. H. J. Verheij (TU Delft, Deltares)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

45 | Master’s Theses October 2011

3

Hydraulic Engineering

Goederenvervoer over water “Implementatie van laad- en loswallen in provinciaal netwerk”

Goederenvervoer over water Door verstedelijking staat de infrastructuur in de provincie Zuid-Holland onder druk. Woon-werkverkeer en goederentransport zorgen dagelijks voor congestie op de wegen in de Randstad, versterkt door de groeiende vraag naar verplaatsingsmogelijkheden. Waar het wegen- en spoornetwerk onvoldoende reservecapaciteit heeft, biedt het vaarwegennetwerk in de provincie ZuidHolland ruimte om transport over water uit te breiden. De provincie Zuid-Holland heeft daarom als doel gesteld om het goederenvervoer over water te stimuleren. Vooralsnog ligt de focus op het technisch opwaarderen van de vaarwegen, echter biedt dat geen garantie voor een toename van goederenvervoer over de provinciale vaarwegen. Overslagfaciliteiten in het vaarwegennetwerk zijn nodig om het overslaan van goederen mogelijk te maken. De nadruk moet voornamelijk liggen op nieuwe overslagfaciliteiten voor containeroverslag. Door de wereldwijde trend in de “containerisatie” van producten en de aanleg van de Tweede Maasvlakte, zal het containervervoer van en naar Rotterdam de komende decennia groeien. Daarnaast zijn er interessante logistieke concepten en een pilot om bijvoorbeeld planten en groenten per binnenvaart te vervoeren over provinciale vaarwegen. Vooralsnog wordt 91 procent van het achterlandtransport van containers tussen Rotterdam en de Randstad vervoerd over de weg.

Watergebonden bedrijventerreinen Twintig kansrijke watergebonden bedrijventerreinen zijn getoetst met scorekaart VL op onder andere “potentiële containerstromen over water”, “interesse gemeente”, ”bereikbaarheid over weg” en “bereikbaarheid over water”. De robuustheid van de uitkomst van scorekaart VL is gecontroleerd met een gevoeligheidsanalyse. Zeven gemeentes, van de negen hoogst gewaardeerde watergebonden bedrijventerreinen uit scorekaart VL, zijn geïnterviewd of er op deze locaties daadwerkelijk initiatieven zijn en ruimte beschikbaar is om overslagfaciliteiten te realiseren. Op basis van gemeentelijk beleid en marktinitiatieven, is een momentopname weergegeven met initiatiefarme en – rijke watergebonden bedrijventerreinen. Mogelijkheden zijn er gevonden op watergebonden bedrijventerreinen

Student: Thesis Committee:

in Delft, Gouda en Katwijk, waarvan de initiatieven in Gouda op dit moment het meest concreet zijn. Op deze concrete interesse is ingegaan door een inpassingsplan te maken voor een containerterminal in de regio Gouda.

Containerterminal regio Gouda Uit gesprekken met diverse bedrijven in de regio Gouda is de potentiële overslag voor een containerterminal in de regio Gouda vastgesteld op 33.000 TEU overslag per jaar, waarvan 4000 TEU concreet. Het terrein van Gouderak BV (bedrijventerrein Middelblok Groot) is voor de realisatie van een containerterminal de meest geschikte locatie, ten opzichte van het terrein van Cyclus op bedrijventerrein Kromme Gouwe. De belangrijkste voorwaarde voor inpassing van een containerterminal op het terrein van Gouderak BV is te voldoen aan de geluidsnormen. Het inpassingsontwerp is gebaseerd op de ontwikkeling van zowel het terrein van Gouderak BV als het naburige terrein van bouwbedrijf Baas. Op het 1,4 hectare grootte terrein kan jaarlijks maximaal 28.000 TEU worden overgeslagen met een mobiele havenkraan en reachstacker. De bodem voor de laaden loswal van de containerterminal dient beschermd te worden om de vorming van erosiekuilen door binnenvaartschepen tegen te gaan. Door het opstellen van een exploitatieberekening is onderzoek gedaan naar de haalbaarheid van de containerterminal. De nadruk ligt op de afweging of intermodaal vervoer tussen Gouda – Rotterdam kan concurreren met wegvoer tussen Gouda – Waalhaven en/of Gouda – Maasvlakte. Vanaf een jaarlijkse overslag van 20.000 TEU is intermodaal vervoer (binnenvaart met voor-/natransport) een goedkoper alternatief tussen Rotterdam – Maasvlakte. Tussen Rotterdam – Waalhaven is intermodaal vervoer alleen concurrerend bij een overslag vanaf 25.000 TEU met beperkt voor-/natransport.

R. van Liere Prof.ir. T. Vellinga (TU Delft), Ir. M. Wolters (TU Delft), Dr.ir. R.J. Verhaeghe (TU Delft), Ir. B.M. Böcker (Provincie Zuid-Holland)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

46 | Master’s Theses October 2011

3

Hydraulic Engineering

Preliminary study of the flushing operations in the Langmann reservoir, Austria

The Langmann reservoir is the most downstream of a series of hydropower reservoirs in the river Teigitsch in Austria. These reservoirs are flushed one by one, leaving the heaviest sediment burden on the Langmann reservoir. Sedimentation-induced reductions of the storage volume used to be compensated by flushing. Environmental concerns for the river downstream (turbidity during flushing operations) led to the withdrawal of the permission to flush. The present study is meant to find sediment management scenarios that cause less turbidity downstream. Upon the request of the dam owner, a Delft3D morphological model of the basin was used in this study, together with literature study and data analysis. Lack of sufficient data and inadequacies of the model made it impossible to come up with more than preliminary conclusions and recommendations. The study does indicate, however, what needs to be done in order to adequately model this kind of phenomena.

Student: Thesis Committee:

Thesis evaluation The lack of data and the inadequacy of the model made this problem hard to tackle. In such a case, the available data and the model can only serve as addons to common sense based on personal observations and circumstantial evidence. As the student’s hard and persistent work remained focused on getting the model working correctly, this common sense approach has received less attention than would have been necessary to solve the problem at hand. Yet, the study has led to a well-written report, including an interpretation of the physical processes at work during flushing and indications of possible solutions to the concentrated sediment outflow causing the turbidity. Also the oral presentation was clear and well-structured, though reflecting the too strong focus on the modelling process. The student’s response to the questions afterwards showed that she had gained good insight into the physical processes relevant to this problem.

V.J.E. den Boer Prof.dr.ir. H.J. de Vriend (TU Delft), Dr.ir. E. Mosselman (TU Delft, Deltares), Dr.ir. C.J. Sloff (TU Delft, Deltares), Dr.ir. A. Blom (TU Delft), Dr.ir. M. Marence (UNESCO IHE, Pöyry Energy GmbH), Dr.ir. A. Crosato (TU Delft, UNESCO IHE)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

47 | Master’s Theses October 2011

3

Hydraulic Engineering

Process-based modelling of coastal dune development

Thesis description

Thesis evaluation

The recent completion of the Sand Engine, a 21,5 Mm 3 mega nourishment located just north of Monster on the South Holland coast, has triggered the interest of Dutch coastal engineers into aeolian sediment transport, because a considerable portion of surface area is located above the water line. This thesis presents the application of an aeolian transport model developed for desert environments as a tool for the evolution of subareal coastal nourishments.

Student: Thesis Committee:

With a great drive, the MSc candidate embarked upon the challenge to implement an existing aeolian transport model for desert environments to the coastal environment. A successful investigation of the driving processes allowed for the extension of the model to the coastal environment. Model results were successfully retrieved showing that the processes of aeolian transport and morphological feedback on the topography are captured. The results are very promising and will contribute to our understanding of aeolian transport. The report and presentation were of high standard.

M.C. Muller Prof.dr.ir. M.J.F. Stive (TU Delft), Dr.ir. J.S.M. van Thiel de Vries (TU Delft, Deltares), Prof.dr.ir. J.A. Roelvink (Deltares,UNESCO-IHE), Ir. S. de Vries (TU Delft), Ir. A.P. Luijendijk (TU Delft, Deltares), Dr.ir. M. Zijlema (TU Delft)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

48 | Master’s Theses October 2011

3

Hydraulic Engineering

Modelling the interaction between morphodynamics and vegetation in the Nisqually River estuary

Thesis description

Thesis evaluation

Due to growing human activity in coastal zones, there is an increasing stress on salt marshes all over the world. These intertidal wetlands were often seen as coastal ‘wasteland’ and large areas were reclaimed for urban development and agriculture. In Puget Sound, a system of interconnected marine waterways and basins in the northwest of the United States, this has led to an 80% loss of marsh area in the last 150 years. In recent years however there has been a growing recognition of their value as habitat for fish, birds and numerous species of plants and as coastal protection. In many countries there are now protected areas and numerous restoration projects are being carried out or planned. One of the largest of these restoration projects takes place in the Nisqually River estuary, in the southern end of Puget Sound. By removing a dike, built in the early 1900s for farming purposes, an area of nearly 405 hectares was reintroduced to the salt water and tides of Puget Sound on November 12, 2009. The goal of this study was to research how this dike removal will affect the estuary.

Student: Thesis Committee:

The MSc candidate enthusiastically embarked on this study researching how the dike removal would affect the estuary in the coming years. With great skill, a computational model was set up in Delft3D to describe hydrological and morphological processes, with a focus on the interaction with vegetation. The vegetation in Delft3D is schematized as cylindrical rods, which add extra source terms to the momentum equation. An external Matlab routine was cleverly extended to calculate changes in the vegetation field based on the model results. Reporting and presentation were of very good quality.

M. Monden Prof.dr.ir. M.J.F. Stive (TU Delft), Dr. J.E.A. Storms (TU Delft), Ir. D.J.R. Walstra (TU Delft, Deltares), Ir. M. van Ormondt (Deltares), Ir. A.C.S. Mol (Deltares)

For further information please contact the section Hydraulic Engineering, 015-2783348 Email: [email protected]

49 | Master’s Theses October 2011

50 | Master’s Theses October 2011

4. Civil Engineering theses

Geo-Engineering

4

Geo Engineering

Het opstellen van een richtlijn voor partieel funderingsherstel

De funderingsproblematiek in Nederland is een probleem van grote omvang. Van zeker 200.000 panden is bekend dat deze te maken hebben met funderingsproblemen. Dat kunnen er in de toekomst meer worden.

Het technische probleem Het aanpakken van funderingsproblemen bij woningen binnen woninblokken is technisch lastig. Doordat de panden constructief met elkaar verbonden zijn, kan herstel van het ene pand invloed hebben op de naastgelegen panden in het blok. Partieel funderingsherstel van woningblokken brengt een risico op schade aan naast gelegen panden binnen de bouweenheid met zich mee. Voor woningblokken met funderingsschade, waarbij de panden constructief met elkaar verbonden zijn, zijn er geen richtlijnen om de funderingshersteleenheid te bepalen. Volgens de huidige inzichten is funderingsherstel per bouweenheid de beste oplossing.

Het maatschappelijke probleem De hoge kosten van funderingsherstel, de overlast tijdens het herstelproces en de onderlinge afhankelijkheid van de pandeigenaren zijn factoren die het funderingsherstelproces beïnvloeden en vertragen.

Voordeel partieel funderingsherstel Het voordeel van partieel funderingsherstel, ten opzichte van volledig funderingsherstel, is dat er kosten worden bespaard en minder panden betrokken zijn bij de uitvoering van het funderingsherstel. Bestaande funderingen met een goede kwaliteit kunnen zo hun functie behouden.

Student: Thesis Committee:

Doel van het onderzoek Het doel van het onderzoek is het opstellen van een richtijn voor partieel funderingsherstel voor laagbouw woningblokken gebouwd op houten palen. Met de richtlijn kan de funderingshersteleenheid van panden binnen een woningblok worden bepaald, waarbij rekening wordt gehouden met het risico op schade.

De richtlijn Naar aanleiding van een literatuurstudie en een serie gesprekken met deskundigen is er een richtlijn opgesteld voor partieel funderingsherstel. Deze is getoetst aan een aantal casestudies. Met de opgestelde Richtlijn Partieel Funderingsherstel kan de funderingshersteleenheid van panden binnen een bouweenheid met funderingsschade worden bepaald. Uitgangspunt daarbij is dat er binnen een vooraf vastgestelde periode (de gewenste handhavingstermijn) geen schade mag optreden binnen het woningblok als gevolg van funderingsproblemen. De richtlijn kan ook gebruikt worden om te toetsen of de geadviseerde funderingshersteleenheid voldoet aan de schadecriteria.

Rol gemeentes De richtlijn biedt een technische oplossing voor het bepalen van de funderingshersteleenheid van woningblokken met funderingsschade. Met de richtlijn is de maatschappelijke kant van het probleem niet opgelost. Aan gemeentes wordt geadviseerd een actieve houding op het gebied van funderingsherstel in te nemen, zodat ook de maatschappelijke kant van het probleem wordt aangepakt.

S. De Lange Prof. ir. A.F. van Tol (TU Delft), Ing. H.J. Everts (TU Delft), Ir. H.R. Schipper (TU Delft), Ing. A.T.P.J. Opstal (Ingenieursbureau Gemeentewerken Rotterdam)

For further information please contact the section Geo-Engineering, 015-2781880 Email: [email protected]

52 | Master’s Theses October 2011

4

Geo Engineering

Time dependent processes on passive loaded piles

The effect of time-dependent processes on passive loaded piles is investigated by means of the finite element program PLAXIS 3D and measurement data from a full scale test. The full scale test is part of an investigation program called GeoImpuls, and consists of a sand embankment of 3 m height on a 3,6 m thick peat layer. The dimensions of the full scale test and the model in PLAXIS are equal. The measurement data from the full scale test are processed into graphs which show the development of the horizontal soil deformation in time at four locations. The piles installed in the full scale test consist of two HEA300 steel profiles, and were installed after construction of the embankment. A square hollow section tube is welded onto the HEA300 in which an inclination measurement can be performed. In order to perform a better determination of the bending moments, the measurement interval of the inclination measurement has been reduced from the regular 0,5 m to 0,1 m. In processing the results a bias-shift has been recognized for which a correction has been applied. The maximum measured displacement of the piles was a few millimetres.

Student: Thesis Committee:

At the site of the full scale test an extensive soil investigation program has been carried out. Soil parameters have been determined in order to use three different soil models in PLAXIS. The used soil models are Soft Soil Creep, Hardening Soil and the S-Clay1 model. The soil models and parameters were fitted by comparing the calculation results with the measured data. The used measured data are; water pressure development underneath the embankment, settlement of the embankment and horizontal soil deformation at two locations. The Soft Soil Creep model gave the best calculation results in comparison with the measured data. The used parameters in the Soft Soil Creep model were further investigated in the soil test module in PLAXIS. This module has been used to simulate real triaxial test data. The calculated displacement of the piles in PLAXIS and the measured displacements were compared to each other and showed good comparison at one location. Two different displacement patterns were recognized both in the PLAXIS calculation and the measured data. In the period close to pile installation when consolidation is the dominant process the maximum deflection of the pile occurs in the peat layer. In later stadia maximum deflection occurs at the top of the pile.

K. Siderius Prof.ir. A.F. van Tol (TU Delft), ing H.J. Everts (TU Delft), Dr.ir. K.J. Bakker (TU Delft), Ir. J.F. Joosse (BT Geoconsult BV), Ir. F.J.M. (Hoefsloot Fugro GeoServices B.V.)

For further information please contact the section Geo-Engineering, 015-2781880 Email: [email protected]

53 | Master’s Theses October 2011

54 | Master’s Theses October 2011

5. Civil Engineering theses

Watermanagement

5

Watermanagement

Land classification based on hydrological landscape units

Introduction: There are always conflicting priorities between lumped conceptual and physically based distributed rainfall/ runoff models. Lumped conceptual models are too simplistic to show the real processes in a catchment although they may fit the hydrograph (runoff) well enough; on the other hand physically based models are too data intensive and they suffer from equifinality, i.e. multiple different parameter sets which lead to the same result. The objective of this study was to break the catchment into hydrologically meaningful units, such as wetland, hillslope and plateau, which exhibit distinct rainfall/runoff behavior. The study area was the 82 km 2 Wark catchment, one of the tributaries of Alzette River in the Grand Duchy of Luxembourg. The idea was to design a lumped conceptual model for each hydrological unit based on expert knowledge within a flexible modeling framework.

Land classification models: In this study three landscape classification models were developed using probability analysis. The classification is based on a newly developed topographical index, the Height Above Nearest Drainage (HAND). Three different classification models were designed using HAND, distance to nearest drainage and slope. The models were calibrated based on visually observed data and evaluated based on an objective function which was developed to evaluate the performance of the model considering each landscape separately. The sensitivity of the classification models were evaluated regarding the number of observed points, the resolution of the digital evaluation model (DEM) and effective smoothing windows which were applied to remove the noise from DEM. The predictive power of the model was evaluated by a split sample test where the model was calibrated for one part of the catchment and tested for another part.

linked to the hydraulic head, can be obtained. For the Wark catchment the model performance was very similar for DEM resolutions of up to 20 meters but it deteriorated for lower DEM resolutions. In other words, for the Wark catchment a DEM with resolution of 20 meters or higher can represent the hydrological units fairly good. The best effective smoothing window size was found to be 120m, while the sensitivity of the best model, which uses HAND and slope, regarding the sample size of calibration points showed that 7 points per km 2 are necessary for adequate modeling. The predictive power of the model was evaluated calibrating for one part of the catchment and testing the model for the rest, e.g. North and South. The result showed that the model performance is good when the model is calibrated for areas with pronounced profile however during validation the model performance is relatively week. When the model is calibrated on areas with subdued profile the calibrated performance is slightly worse however the performance of the model in the test area is more consistent.

Conclusion: HAND is a more powerful indicator for landscape classification than the frequently used elevation above sea level. HAND gives more information regarding the structure of the catchment because it is normalized with local hydrological feature (river) and it reflects the interaction of hydrology and topography.

Recommendation: This study shows a catchment can be classified into different hydrological units with help of HAND. The next step is to investigate the performance and efficiency of these models using measured field data such as soil moisture.

Results: The result showed that the model using HAND and slope performs better than the model using distance and slope. It showed that by extracting HAND from relatively uninformative elevation above sea level a far more informative and hydrological meaningful metric, directly

Student: Thesis Committee:

S. Gharari Prof.dr.ir. H. H. G. Savenije (TU Delft), Prof.dr. S. Uhlenbrook (UNESCO-IHE), Dr. M. Hrachowitz (TU Delft), Dr. F. Fenicia (Gabriel Lippmann Research Center)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

56 | Master’s Theses October 2011

5

Watermanagement

Urban surface water quality enhancement. A case study on a floating helophyte filter

Ongoing urbanisation and the subsequent extensive use of the urban water system can lead to degradation of its surface water quality. In the Netherlands, urban water bodies often suffer from the manifestations of eutrophication due to (historically) high nutrient loadings. This research focused on the enhancement of surface water quality of semi-confined urban water bodies with a case study on a floating treatment system. Urban water bodies often function as amenities of the urban area. Their ornamental and ecological value depends on the state of their aquatic ecosystem. Excessive nutrient loading, leading to the collapse of the system’s biodiversity, turns a water body into a turbid state without submerged macrophytes. Restoration of the clear water state through reduction of nutrient loadings alone is hindered by hysteresis caused by the ecosystem relations and could be supplemented with an approach focused on increasing the system’s nutrient carrying capacity or an internal approach directly targeting the manifestations of eutrophication. The Bright Water Company floating helophyte filter actively drains a filter bed with bog plants growing in it. The influent of this biofilter is provided by free inflow of surrounding surface water. Its water treatment ability depends predominantly on filtration and adsorption by specific nutrient absorbents. Additionally, its inner reservoir could serve as a habitat for small aquatic organisms.

Student: Thesis Committee:

Insights on the functioning and applicability of the biofilter were gained through in situ measurements. Two biofilter were applied in the Floresvijver in Groningen and measurements were conducted on influent, effluent and surface water. Visual observations and laboratory analyses of the water samples showed effective filtration and daphnia flourishing in the inner reservoir of the biofilter. Accumulation of the residual solids as a sludge layer on top of the filter bed and formation of biogas inside the filter material proved to reduce the hydraulic capacity significantly. Nutrient removal efficiency could not be determined with the monthly measurements of the water board but for optimal functioning of the phosphorous absorbent the current filter bed design should be adjusted while effluent samples indicated leaching of absorbent components. Application of optimal functioning biofilters can contribute to the enhancement of urban surface water quality by increasing the nutrient carrying capacity of a water body. Especially in urban areas with various diffusive nutrient sources and physical constrains limiting other measures, the application of this biofilter can be efficient. Additionally, the biofilter functions as a habitat for zooplankton which are an important ecosystem element for the prevention of algae blooms. Furthermore, the effluent of the biofilter can provide a local increase in transparency and improve conditions for macrophyte development.

M.R. van Dieren Prof.dr.ir. N.C. van de Giesen (TU Delft); dr.ir. F.H.M. van de Ven (TU Delft); Drs. B. van der Wal (TU Delft); Dr.ir. J.A.E. ten Veldhuis (TU Delft); M. Siers (Bright Water Company)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

57 | Master’s Theses October 2011

5

Watermanagement

Unembanked Areas – A risk assessment approach

Areas outside the primary flood defenses, here called unembanked

A multi-layer safety approach assumes three layers in flood

areas have a special status in the Dutch water safety policy.

control:

Whereas, primary flood defenses have to fulfill to legal standards

1.) Prevention: characterized by structural measures which

and a functional manager is appointed for construction,

influence the boundary conditions of the project area. Surface

maintenance and management. For unembanked areas this

level heightening and the construction of an embankment are

situation is different; some provinces have water safety policy

discussed

and according to the national water plan residents and users

2.) Spatial planning, characterized by structural measures which

are responsible for taking consequence reducing measures of

influence the exposure and vulnerability. Wet proofing, dry

floods. For the development of new areas decisions have to be made about the desired level of safety and how this is achieved.

proofing and an elevated configuration are discussed. 3.) Disaster control, characterized by non-structural measures

This leads to the issue of optimal adaptation strategies. What

which influence the exposure and vulnerability. Organizational

is the best level of safety so that unnecessary high risk levels

aspects and financial compensation are discussed.

and overinvestment in safety related infrastructure can be circumvented? This study presents a framework for municipalities

It was founded that the urban dwelling density of a project area

and property developers how to deal with flood risk in

determines the profitability between individual consequence

unembanked areas.

reducing measures (layer 2 of the MLS approach) and collective

952 developments are planned in unembanked areas of which 183

probability reducing measures (layer 1). The profitability of

comprise urban dwelling projects. This thesis especially focuses on

collective measures grow linear and transcend individual measures

these urban dwelling projects where flood events can be regarded

at 24 dwellings/ha. An elevated configuration is preferred

as a local, regional and direct tangible risk. The following research

above wet and dry proofing. Considering the construction of an

question is answered:

embankment it was founded that the profitability grows according to a power function and transcends surface level heightening at

How can we deal with the uncertainties of flood risk in investment

35 ha. All proposed urban dwelling plans in unembanked areas

decisions in the development of unembanked areas?

are analyzed on these criteria and it was founded that for 23%

1. What is the current policy of building in unembanked areas and

of the plans individual measures are preferred above collective

what are the responsibilities of the government? 2. Which strategies can be formulated to create the desired level of safety and how should they be compared? 3. How can a multi-layer safety approach contribute to the safety 4. How do area specific characteristics influence the cost 5. How to deal with the residual risk?

the province has no flood probability standards and therefore consequence reducing measures have a good chance. The other 38% of the plans are located in provinces with flood profitability standards and the profitability of extra consequence reducing

of the project area? effectiveness of the measure?

measures. 62% of these plans are located in areas where

measures is dependent on this standard. For the remaining 77% of the areas a probability reducing approach is preferred; of which for 6% the construction of an embankment is preferred and for the other a surface level heightening strategy is preferred. All criteria of insurability (grouped in actuarial, market-determined and societal) are analyzed for a flood damage insurance for unembanked areas. Due to the physical aspects and policy of unembanked areas the formulated criteria of insurability score better for unembanked areas. The actual realization will depend on the market determined criteria. This approach has been tested for a redevelopment project in Rotterdam, Heijplaat, where it was founded that surface level heightening is the only profitable measure.

Student: M. Wolthuis Thesis Committee: Prof.dr.ir. N.C. van de Giesen (TU Delft), Dr.ir. O.A.C. Hoes (TU Delft), Prof.dr. S. Schaap (TU Delft); Ir. S. de Boer, (DHV) For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

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Watermanagement

Performance assessment of tree-based model predictive control

More is demanded from water systems every day. Man induced changes, like increasing population density and increasing land value on one hand and climate change in the form of longer dry spells and more extreme precipitation events on the other hand are the main sources. The operation of the structures in these systems plays a critical role in successfully dealing with these challenges. To get the most out of the current system and its structures, operation by humans alone is not enough, they need to be aided by computers. A promising technique is Model Predictive Control (MPC). A control algorithm that uses a model of the system and forecasts of the future disturbances to determine the control actions for the structures, whilst adhering to the constraints of the system. Forecasts are uncertain and are therefore provided in the form of ensemble forecasts that consist of multiple scenarios. MPC uses only one scenario and is thus vulnerable to these uncertainties. Tree-based Model Predictive Control (TBMPC) considers the complete ensemble to determine control actions. TBMPC has, however, only been tested in theory. Only open loop simulations have been carried out, no continuous closed loop simulations have been done. TBMPC uses the complete ensemble, but to save calculation time reduces it to a tree-shaped representative ensemble with fewer nodes. This means aggregating nodes and scenarios on various points in the ensemble. There are multiple rules that determine which nodes and scenarios are aggregated, however, their optimal setting is not known. Also if TBMPC has more added benefit over MPC on certain system configurations (e.g. configurations with higher discharge or storage capacity) is not known either.

nodes and scenarios to aggregate yields better results. The threshold value is also important as it determines whether or not two scenarios are close enough to each other to be aggregated. The optimal value is 100% of the maximum pump capacity. The scenario reduction algorithm (i.e. the algorithm that creates the tree from the original ensemble) has two parts. First it reduces the number of scenarios in the ensemble to a predefined number and secondly it creates a tree out of the reduced ensemble. The simulations show that using more than eight to 10 scenarios does not yield any better performance, but only increases calculation time. To determine if TBMPC is more beneficial on certain system configurations 81 configurations are examined. For all configurations TBMPC shows a considerable added benefit over MPC, however, there are different reasons for different configurations. For configurations with a high storage and pump capacity the increased performance can be attributed to a more stable water level and a slight improvement in the deviation from set point. For configurations with a low storage and pump capacity the added benefit of TBMPC is seen in a better peak event anticipation. Overall significant improvements to TBMPC have been realized. It is shown that TBMPC not only works in theory, but provides benefits over MPC in practice for a multitude of configurations as well. TBMPC can now be tuned to the water system configuration it is used on and it can be set to reduce calculation time as much as possible without decreasing the performance.

A model is developed to simulate the performance of MPC and TBMPC. It can deal with different precipitation series, forecasts, system configurations and control algorithm parameters. All simulations have a duration of one year and a one hour time step. The rules that determine which nodes and scenarios are aggregated are investigated first. Transforming the inflow forecast scenarios to cumulative inflow scenarios before determining which

Student: Thesis Committee:

P.M. Stive Prof.dr.ir. N.C. van de Giesen (TU Delft), Ir. L. Raso (TU Delft), Dr. R.R. Negenborn, (TU Delft), Dr. D. Schwanenberg, (Deltares)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

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Watermanagement

Rainfall fed inundation in greenhouse dominated polders; Research of water system assessments

Since the end of the last century, polders in the Netherlands have suffered from inundation due to heavy rainfall. Inundation occurrences in 1998 have led to large economic losses, especially in polders with a fast rainfall runoff process due to the high percentage of land occupied by greenhouses. This thesis focuses on water system assessments, conducted in greenhouse dominated polders. The water system assessment is divided in a technical analysis (using a hydrodynamic model) and an analysis on the cooperation between the different parties involved in water management. The inundation of 1998 had a large impact in the area managed by the water board of Delfland. As a reaction to the inundation, policies were created containing storage capacity standards for the open water of polders. Based on these standards the project ABCDelfland (Afvoer- en Bergings Capaciteit Delfland, in English: Drainage and Storage Capacity Delfland) was started, in which water systems of main canals and polders were assessed. The polder assessment was aimed at reviewing if the new standards were met. In the assessment the water board focused on the water system under its own control. The focus of that study was not on how to solve the inundation problem, but on how the open water system could comply with the standards. The solutions which were identified to make the water system meet the standards were financially not feasible. It was found that a better representation of the water system was needed to develop new solutions. Cooperation between the parties involved in water management would be needed to make this happen. This study was conducted to improve the assessment methods of rainfall fed inundation in greenhouse dominated polders. It uses the Oranjepolder (located in the management area of the water board of Delfland) as a case study, since inundation has occurred several times in this polder and is well documented and parties are engaged in finding new innovative solutions for the problem. In this assessment a form of participatory modeling was applied. Input for a new hydrodynamic model was given by all parties involved in the management of water in the Oranjepolder. The water board of Delfland is responsible

Student: Thesis Committee:

for the management of the open water, the sewer systems are managed by the municipality of Westland and horticulturists influence the runoff to open water by the storage of water in basins. By sharing information and experiences during workshops, this research has been made possible. Through the cooperation of these parties, the important elements of the water system and the key to future solutions are identified. A hydrodynamic model of the Oranjepolder with a high level of detail is achieved. All important hydrologic processes are included. The hydrology of greenhouses is included on an individual level, resulting in a runoff to open water which represents the actual situation. Secondly, the channel flow model contains all channels and water structures located in the polder. This makes it possible to review inundation at every channel. Thirdly, the sewer system of the village Maasdijk is included in the model. Water flowing out of manholes and the interaction between the sewer and open water system are made visible. Finally, the aspect of overland flow is included. By taking all these hydrologic processes into account, predictions with a high level of precision can be made. The high level of detail and the high precision of the model lead to better insight in the factors that influence inundation. Testing the model with real rainfall data resulted in the identification of multiple inundation locations, which were also reported in reality. Due to this high predictive value it was possible to devise precise measures to prevent future inundation. These measures are not confined to the open water system but also concern the sewer system and the hydrology of greenhouses. It is expected that the total cost and amount of land needed, will be substantially lower than in previous assessments and that all stakeholders will support the implementation of measures.

B.C. Albers Prof.dr.ir. N.C. Van de Giesen (TU Delft), Dr.ir. P.E.R.M. Van Leeuwen (TU Delft), Dr.ir. J.A.E. ten Veldhuis (TU Delft), Drs.ir. S. Jouwersma (Hoogheemraadschap van Delfland), Ir. J.G. Leskens (Nelen & Schuurmans)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

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Watermanagement

Prediction of temperature distribution in a Drinking Water Network Introduction

According to the Dutch Drinking Water Directive the temperature of drinking water should remain below 25°C at the customers’ taps to prevent microorganisms proliferating in the distribution mains and to ensure a supply of water that is qualitatively and aesthetically stable. However, the water temperature in a distribution network is difficult to control as it depends on multiple factors including: climatic conditions, surface conditions, soil characteristics and drinking water discharges.

Problem definition Recent studies demonstrate that the rising global mean temperatures as projected by the International Panel on Climate Change are likely to be manifested in an increase of the temperature of the surface water systems and of the soil. Therefore, it is likely that also the temperature of drinking water will increase and drinking water supply companies may find themselves in a situation of temperatures approaching legally imposed standards.

Research The principal goal of this research was to explore how network hydraulic influences the temperature of the drinking water. The secondary aim was to establish linkages between climate conditions, network characteristics and the drinking water temperature. To achieve these goals, we have used a model instrument consisting of two heat transfer models representing weather and soil conditions, and two network models calculating hydraulics and water quality. In order to validate the models’ an experiment was organised. An experiment was conducted to observe the soil at the three different depths below the surface simultaneously with the drinking water temperature. The observation unit was repeated at four different locations in a network, that featured different surface covers and pipe characteristics.

Student: Thesis Committee:

Results The evaluation of a capability of a combined weather and soil-diffusion models to estimate pipe wall temperatures has led to inaccurate results; however the models we have used carried useful information for network calculations. Secondly, numerical network simulations at the heat wave conditions, indicate significance of the residence time and gradient between the soil and drinking water temperatures. However results from this case study demonstrated that the gradient between the soil, pipe wall and the drinking water temperatures was small. It was difficult to determine a clear influence of the hydraulic on the diurnal cycle of the drinking watersoil temperature exchange.

Conclusions and recommendations This study proved an applicability of the model instrument to predict a temperature of the drinking water. However, heat transfer modelling approach requires additional improvements towards models’ accuracy, and an account of precipitation and soil moisture. The reliability of the methodology used in this thesis, should be verified for summer conditions when the air, net global radiation and soil temperature exhibit stronger diurnal fluctuations.

L. Magda Prof.dr.ir. N.C. van de Giesen (TU Delft), Prof.dr.ir. L.C. Rietveld (TU Delft), Ir. M.M. Rutten (TU Delft), Dr. M. Dignum (TU Delft), Ir. S. Viester (TU Delft)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

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Watermanagement

A new suit for the IJsselmeer Possibilities for facing the future needs of the lake by means of an optimized dynamic target water level Introduction and problem definition The IJsselmeer is located in the center of the Netherlands. For its relevance for the Dutch economy and society, it is often addressed as the Wet Hearth of the country. When looking into the future, the IJsselmeer is under climate threats. Wetter winters will bring more water into the system, in combination with sea level rise, and lower gravity discharge to the Waddenzee. This will generate safety issues. On the other hand summers will be drier, putting the satisfaction of water demand in danger.

Research approach and research question The goal of the research is to define for the IJsselmeer a dynamic target water level which is variable through the whole year by means of an optimization approach. The optimization uses a single objective function considering dikes safety and water demand. Such approach has been chosen because follows a different path than the ones mainly used so far to tackle the issue. When management measures alone are not enough to define a climate-proof IJsselmeer, extra measures are taken into consideration: a pumping station at the Afsluitdijk and early storage in March. The main research question asks for an evaluation of the optimization methodology used to define efficient alternatives for the IJsselmeer. The sub-question requires the assessment of the flexibility of the IJsselmeer towards a climate-proof system, and the definition of extra measures, when needed.

Methodology The definition of the optimum measures is achieved in several steps. Firstly the objective of the problem owner is defined. The Dienst IJsselmeergebied is the only problem owner. Its interests are safety and water demand satisfaction. Then indicators are derived from the objectives, and merged into the objective function. Classes of measures are selected, and a model of the system designed for their evaluation. Finally the optimization problems are defined in order to design the optimum alternatives.

Student: Thesis Committee:

Results A different planning of the target water level alone is not able to satisfy the needs of safety and water demand on the long term. As it is now, the IJsselmeer is flexible on the short term, but not enough to accommodate the impacts of longer horizons: extra measures are needed in order to define a climate proof system in 2050 and 2100. Pumping station at the Afsluitijk is an effective measure to guarantee safety for all the scenarios. Early storage in March is effective in the medium horizon (2050) but need high target water levels along the summer for the long term (2100). This might generate safety issues. Even if applied on a simplified case, the use of an optimization methodology manages to define a realistic picture of the flexibility of the IJsselmeer, and retrieves efficient options for possible future strategies. For this reasons, the present research can be considered a successful implementation of an optimization approach for the Ijsselmeer.

Conclusions and recommendations For the short term it is recommended to use the flexibility of the system, implementing the changes in summer target water levels which would allow deeper satisfaction of water demand. For the medium/long term, options for early storage need to be investigated together with the summer target water levels needed. This would probably require reinforcement of the dikes. Options for safety can be then defined for the new reinforced system, considering combinations of pumping station and raise of the dikes. A more extensive and detailed optimization tool should be realized for the IJsselmeer, and applied for the definition of the measures above. In particular it is recommended to use a multi-objective analysis and include costs in the definition of the indicators.

J. Talsma Prof.dr.ir. N. de Giesen (TU Delft), Dr.ir. P.J. van Overloop (TU Delft), Ir. R. Slomp (TU Delft), Dr.ir. J. Timmermans (TU Delft), Ing. A.G.M. de Vrieze (TU Delft)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

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Watermanagement

A fresh-keeper for Noard Burgum

Introduction

Conclusions

The drinking water company Vitens extracts groundwater for its drinking water production from the area of Noard Burgum, a village in the north west of the province of Fryslân. In particular, two well fields have been used, the well field Storm and the well field of Ritskebos. The total production of both well fields was 25 Mm 3/y in 1978. These large extractions increased the attraction of distant salt. To limit this process, the extraction was gradually reduced from 1978 and even lead to closure of the well field Storm in 1993, now referred to as the Old Well Field. In 2010 the total extraction is 7.5 Mm3/y, using only the Ritskebos well field. To meet the future demand and at the same time to assure that the distributed water still meets the 150 mg/L drinking water standard for salinity, Vitens installed a test pilot of the fresh-keeper at the Old Well Field. The fresh-keeper is a groundwater well with an additional well screen near the bottom of the aquifer. The two screens separate fresh and brackish water extractions. Brackish water that is extracted near the bottom of the aquifer is filtered by reverse osmosis, producing a volume of desalinated water. This is mixed with the extracted fresh water and used for drinking water production. In the rest of the flux salt is concentrated and injected below a clay layer, called the Clay of Tegelen, in a deeper aquifer with a similar concentration. In this way, drinking water production can continue in a brackish environment. Until now, the freshkeeper concept has only been tested in small scale pilots.

Objective and method

It was shown previously that the fresh-keeper concept works in practice. In the fresh-keeper pilot both wells extract the same volume. The objective of a brackish water well is, however, to extract just enough water to keep the upper well fresh. The current study shows that the amount of extracted brackish water may be reduced in Noard Burgum, thanks to the sharp interface between fresh and brackish water. Even to the extent, that reverse osmosis is no longer needed. The advantage of untreated water is that it is not regarded a waste product when injected. If a fresh-keeper well field was installed, it would initially extract brackish water coming from all directions, but after about a decade ever more fresh-water is being extracted from the south-west. Over time, some of the initially brackish screens will therefore even become completely fresh. This should be accounted for in a well field design, by creating the possibility to reduce the brackish water extraction in the south west direction only. It is concluded that the fresh-keeper method is effective and could be implemented in Noard Burgum without the need for reverse osmosis. Model predictions of lateral salination have been made till 2050, and show no further increase of salt as a result of the additional extraction in Noard Burgum of 3.5 Mm3/y, which includes the brackish water extraction. Its effect on future salination through the leak was, however, not quantified, because more information is needed about the salt distribution below the Clay of Tegelen.

The objective of this study is to determine the feasibility of the fresh-keeper concept for producing 3.0 Mm 3/y of drinking water at the Old Well Field in Noard Burgum. To evaluate the feasibility of the fresh-keeper in the area, a geohydrological flow and transport model was used. This model was calibrated with and compared to measured data and input from previous salinization studies at this site.

Student: Thesis Committee:

M.J.H. van der Valk Prof.dr.ir. T.N. Olsthoorn (TU Delft); Ir. A.T. Oosterhof (Vitens), Drs. F.J.C. Smits, (Waternet), Dr.ir. M. Bakker (TU Delft), Prof.dr. J. Bruining (TU Delft)

For further information please contact the section Water Management, +31 (0)15 278 1646 Email: [email protected]

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5. Civil Engineering theses

Transport & Planning

5

Transport & Planning

The use of probe data from consumer GPS navigation devices for the analysis of controlled intersections

Probe data from consumer GPS navigation devices provides a network-wide and cost-efficient data source for measuring vehicle movements. The measurement of traffic volume, route choice and delay on intersections is needed for efficient intersection control. Data collection from road-side sensors can provide this information but is expensive and requires high maintenance expenditures. Probe vehicle data provides an interesting alternative although experimental studies have been confined to small datasets. This study presents the results of intersection performance measurement using a large probe dataset from consumer GPS navigation devices.

Student: Thesis Committee:

The study shows that probe data from consumer GPS navigation devices provides a suitable data source for the determination of route choice and delay at two test case intersections if a sufficient sample size is available. Route choice is measured with an average error of 1.35% to 3.76%. This new data source is beneficial for a quick assessment of the delay and route choice at intersections, including intersections without fixed detectors or where data from stationary detectors is not easily accessible.

A.M. Meijer Prof.dr.ir. B. van Arem (TU Delft), Prof.dr.ir. B. De Schutter (TU Delft), Dr.ir. A.M. Salomons (TU Delft), Ir. P.B.L. Wiggenraad (TU Delft), Drs.ing. P. Krootjes (TomTom International B.V.), N. Cohn MSc. (TomTom International B.V.)

For further information please contact the section Transport & Planning, 015 2789341 Email: [email protected]

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Transport & Planning

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6. Last year’s Theses

6

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

Hydraulic Engineering The cause of coastal erosion on a nourished beach in Kololi, The Gambia Student: E. Bijl

Double curved precast load bearing concrete elements Student: B. Janssen

Influence of the armour layer and core permeability on the wave run-up Student: P.J.M. van Broekhoven

The effect of steel plate girders with a high slenderness upon the fire resistance Student: R. Wiersum

Feasibility study on the use of a floating breakwater to protect a new artificial beach in Balchik, Bulgaria Student: R. Drieman

Parkeerkelder met een pneumatisch caisson Student: S.P. Rodrigues Monteiro

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) Modelling the equalizing process of rockfill dumps with a plough Student: W. Kranendonk

Structural Engineering 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 CO2-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

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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

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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

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

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

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

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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

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Last year’s Theses

Master’s Theses October 2010

Civil Engineering theses Structural Engineering Structural Failure in the Netherlands Student: W.F. Boot Special Nodes in Ultra High Performance Concrete Student: Hasan Han Corrosion of steel reinforcement in 12 years old concrete: Inspection, evaluation and electrochemical repair of corrosion Student: J. Pacheco Farias Design of walls with linear elastic finite element methods Student: M. Romans V-shaped pylon concept Student: J. van Weerdenburg The feasibility of full 3D modeling of concrete viaducts Student:N.W. Kostense

Design tool for determining the sustainability of structural designs Student: F.T. Tool Crack formation in structural slabs on underwater concrete Student: W.H. van der Woerdt

Hydraulic Engineering “Layout design for greenfield port Filyos” Student: L.B. Donders Undesired reshaping of exposed core material Student: P.H.M. Mulders Experimental research on spatial distribution of overtopping Student: A. Lioutas Sharp bend flow Student: A. van Sabben Analysis of the Carbon Footprint of coastal protection systems Student: A.L. Labrujere

Autogenous and drying shrinkage Student: Jan van Capellen Phenomenological modeling of ice induced vibrations of flexible offshore structures Student: H. Hendrikse The effect of the introduction of the eurocode on the safety level of excisting platebridges Student: Frank Schotman

An analysis of vessel behaviour based on AIS data Student: Thijs de Boer Tidal influence on sediment transport and bed level in the river Merwede Student: A.L. de Jongste (MSc Hydraulic Engineering) Aeolian transport on beach based on field measurement on the Dutch coast Student: Marion Coquet (Coastal engineering)

Building Engineering Damage investigations in concrete buildings Student: Carolina Miró-Downey Sustainable Facade for the Energy museum Student: S. Esmailzadeh Structural feasibility study and design of a portable stadium Student: A.H. den Hollander “Parametric Collaboration Tool” from architectural input to engineering output Student: Oswald Verbergt

“The influence of core permeability on armour layer stability” Student: H.D. Jumelet Behaviour of segment joints in immersed tunnels under seismic loading Student: Ruben van Oorsouw Numerical modeling of sediment transport over hydraulic structures Student: Vincent Vuik Cross-shore morphological response on Chaland Headland due to Hurricanes Gustav and Ike

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Student: S.N. Kuiper Cobble Sea Defence: Hydraulic Interface Stability of Sand underlying a Single Filter Layer Student: Arthur Zoon Model a dynamic equilibrium of yearly averaged salinity in the Pontchartrain Basin Student: S. van den Heuvel Failure of rubble mound breakwater’s armor layer Student: unknown Behaviour of nourishments in quasi 3-dimensional graded sediment models Student: unknown Pilot Sand Groynes Delfland Coast Student: unknown Dong Lam Cement Factory Student: W.A. (Wouter) Broersen Probablistisch diepteontwerp voor binnengebied haven Rotterdam Student: Y. Abdelouarit New Profile for the Amsterdam-Rhinecanal Student: L. Lievense Master plan Porto Romano Bay, Albania Student: M.K. Kersten

Geo-Engineering Bentonite cavities in diaphragm walls Student: A.J. Lubach The adaptation of the method URUP for the Netherlands Student: A.J. Beijer Process and stability of slow moving landslides Student: Eva Johanna Sloof Modelling horizontal soil deformations Student: C.W.J. te Boekhorst

Transport & Planning Dynamic Speed Limits: Extension and Application Student: Ilse Schelling

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Last year’s Theses

Master’s Theses July 2010

Civil Engineering theses Structural Engineering Simulation of steel-concrete bond-slip with sequentially linear analysis using interface elements Student: S.W.H. Ensink (Environmental) costs in the Dutch civil concrete industry Student: M.R. de Moel Sequentially Linear Analysis of Shear Critical Reinforced Concrete Beams Student: A.T. Slobbe Third tier on the Amsterdam ArenA Student: J.F.Y. Smeets Proposal New City Bridge, Nijmegen Student: S. Weusthof

Controlling extreme waterlevels on Lake IJssel Student: Rindert de Jong The evolution of sandbars along the Colorado River downstream of the Glen Canyon Dam Student: L. Kemp Rüttel-Injectiepalen: Ontwerp, proef, monitoring en modellering Student: I. van Kempen Wave impact on grass covered outer slopes Student: B.C. Mous Experimental research on the effects of a surface screen on a mobile bed Student: Siem Troost Hydrodynamic pressures on large lock structures Student: M. Versluis Salt based dam design in a hyper saline environment Student: Carina Wierda

Building Engineering Seismic Risk Mitigation in Greece Student: Dimitris Detsis

Ontwerp voor de toekomstige Merwedekering Student: T. Wijdenes

Reinforcing glass with glass: Application of transparent reinforcement in structural glass beams Student: C.C.K. Leung Usage of lifts for the evacuation of high-rise projects Student: R.H.J. Noordermeer “The differences in risks between EPIC and Traditional projects” Student: O. Rienks Structural design of ‘The Wave’ Student: S.A. Sligman

Hydraulic & Geo-Engineering Boussinesq-type wave modelling in port applications Student: Joas Boeyinga Morphodynamic modelling of the Galgeplaat Student: I.L.L. Das Master plan coastal haven, “Nikas”, Kuwait Student: J.C.S. Geerlings

Watermanagement The potency of applied control theory on the river Linge Student: J.W. Bronkhorst A fast method to assess biological stability during drinking water distribution Student: T.J. van Delft Performance comparison of LP vs. MP mercury vapour lamps Student: Josanne Derks Calibrating a Hydrological Model on Vegetation Data: Application on Drylands Student: Ing. J.A. Flapper Herstellen van de wincapaciteit van de Amsterdamse Waterleiding Duinen Student: M.M.Houdé The influence of hydraulics and spatial differences on the daily practice within an irrigation system A case study in Arequipa, Perú Student: E.E. Koopman

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Prediction of temperature distribution in a Drinking Water Network Student: L. Magda Nood op de Boezem Student: J.W. Nelissen Staying ahead of the flood; The influence of higher resolution flood simulation models on the accuracy and visualisation of information. Student: O.K. Pleumeekers

Transport & Planning Reconnecting Rotterdam Port Student: Aart de Koning Development of an assessment framework to weigh conventional and unconventional interchange designs based upon literature research and micro-simulation Student: Arjan van der Palen Coordinated signal control for urban networks by using MFD Student: Maarten Strating Microscopic interaction behavior between individual pedestrians Student: Dirk Versluis Accident modelling of road intersections in The Hague Student: P.H. Voorburg Sustainable mobility at urban development Student: Yvonne van Zon

Theses Offshore Engineering The design of an offshore floating lifting vessel specialized in installing wind turbines Student: Yannick Van Hoof Selection of limiting Sea States for Offshore Wind Turbine Installation Student: Jaap Pieters Air-gap assessment during severe weather conditions Student: Bart Slingerland

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Research Groups and professors within the faculty

Research groups and professors within the faculty of Civil Engineering and Geosciences

Specialisation

Name

Construction Mechanics Research Group Construction mechanics Dynamics Numerical mechanics

Prof. J.G. Rots Prof. A.C.W.M. Vrouwenvelder Prof. L.J. Sluys

Design and Construction

Telephone 015-27. . . . .

83799 84782 82728

Materials Science and Sustainable Construction Research Group Acting chairman Prof. K. van Breugel

84954

Road and Rail Engineering Research Group Road Engineering Rail Engineering

84812 84812

Prof. A.A.A. Molenaar Prof. A.A.A. Molenaar

Building and Civil Engineering Structures Research Group Concrete structures Prof. J.C. Walraven Concrete modelling & materials Prof. Ir. A.Q.C. van der Horst Timber structures Prof.dr.ir. J.W. van de Kuilen Steel structures Prof. F.S.K. Bijlaard Utility buildings Prof. J.N.J.A. Vamberský

85452 87014 82322 84581 85488

Product Design Research Group Methodical Design

Hydraulic Engineering Fluid Mechanics Research Group Fluid Mechanics Environmental hydro informatics Sediment Dynamics Physical Oceanography

Prof.dr.ir. G.S. Stelling Prof.dr.ir. W.S.J. Uijttewaal Prof. Dr. Ir. J.C. Winterwerp Prof. Dr. J.D. Pietrzak

85426 81371 84582 89455

Hydraulic and Offshore Engineering Research Group Probabilistic design and Hydraulic Structures Coastal Engineering Ports and Inland Waterways Environmental River & Estuaria Engineering

Prof. Prof. Prof. Prof.

85278 84285 85075 81541

J.K. Vrijling M.J.F. Stive Ir. T.Vellinga H.J. de Vriend

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Last year’s Theses

Specialisation

Name

Sanitary Engineering Research Group Sewerage Waste Water treatment Drinking Water

Prof. F.H.L.R. Clemens Prof.dr.ir. J.B. van Lier Prof. J.C. van Dijk

83347

Prof. H.H.G. Savenije Prof. N.C. van de Giesen Prof. Th. N. Olsthoorn

81433 87180 87346

Prof. Bastiaanssen Prof. W. van Vierssen

87346

Water Management

Water Resources Research Group Hydrology Water Resources Geohydrology Water Resources Management and Earth Observations Science System Assessement

Telephone 015-27. . . . .

81615 85227

Transport & Planning Traffic Modeling Traffic Safety Transport and Traffic Networks Traffic and Transport Management Traffic and Transport Facilities Infrastructure Planning Traffic Flow Theory and Simulation

Prof. Dr. Ir. B. Van Arem Prof. Ir. F.C.M. Wegman Dr. R.A. Zuidwijk

86342

Prof. I.A. Hansen Prof. F.M. Sanders Prof. S.P. Hoogendoorn

85279 81780 85475

Prof. S.B. Kroonenberg Prof. S.M. Luthi

86025 86019

Petroleum Engineering Research Group Oil- and Gas production Engineering Reservoir Technology Reservoir Engineering

Prof. P.K. Currie Prof. W.R. Rossen Prof. C.P.J.W. van Kruijsdijk

86033 86038

Applied Geophysics and Petrophysics Geophysical Imaging Methods Technical Geophysics

Prof. W.A. Mulder Prof. C.P.A. Wapenaar

83666 82848

Geo Engineering Research Group Groundwater mechanics Foundation Engineering Underground Space Construction Geo environmental engineering

Prof. Prof. Prof. Prof.

85423 85478 82844 86032

83346

Applied Earth Sciences Applied Geology Research Group General Geology Production Geology Resource Engineering Research Group

F.B.J. Barends A.F. van Tol J.W. Bosch J. Bruining

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