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Introduction Flooding is a natural phenomenon, but human activity has significantly altered the natural drainage processes thereby occasionally causing greater flood risk. Urban flooding has become more frequent due to a number of factors including climate change, urban growth and an increase in paved surfaces. Pluvial flooding results from heavy rainfall when water that does not infiltrate into the ground ponds in hollows or flows over the ground. In flood damage estimation, the concept of damage curves or damage functions is applied. Such functions give the building damage due to inundation. Most damage assessment models have in common that the direct monetary damage is obtained from the type of the element at risk and the inundation depth. Problem definition Flood damage assessment models do not focus solely on pluvial flood damage estimation. In addition, the existing flood damage models and developed depth-damage curves have not been tested for application of pluvial flood events. Research This study is carried out with the main objective to test the flood damage assessment model HOWAD-PREVENT in a case study in Rotterdam and to evaluate the uncertainty and sensitivity of this model. The model applicability and sensitivity was tested by running the model with two building type files together with three water level files.

Introduction Flood risks can be reduced by either reducing the probability or the consequences of a flooding. These consequences can be quantified with flood damage models. Such models determine flood damage based on the water depth and the land use. This thesis will investigate the need to also use the flood duration as input parameter. Problem definition Besides the water depth, also other factors determine the resulting flood damages. These factors are often not taken into account in flood damage models. One of these influences is the flood duration. The longer a flooding lasts, the larger the material damage, and especially damage due to interruption will be. Flood duration causes interruptions and extra material damages. Taking into account flood duration can, therefore, theoretically make flood damage models more accurate. Flood duration predictions are, however, at the moment rarely done. This thesis aims to get both a qualitative and quantitative understanding of flood duration and the importance of flood duration for damage assessments. Research This thesis aims to explore the possibilities of assessing flood duration for flood risk management. This is approached by the following steps. 1. Development of a better understanding of flood duration. By looking at different areas and flood threats, a flood type categorization was developed and durations were estimated for each flood type 2. Exploration of the influence of flood duration on damage. A modeling method to roughly estimate the duration-dependent damage was developed. The framework of this method may also be useful for future duration dependent flood damage models. 3. Two case studies were carried out to study flood duration and its influence on damage in more detail: First the Betuwe and Tieler & Culemburgerwaard area was studied and secondly the area threatened by a breach at the Parksluizen in Rotterdam was focused on. Different scenarios were used with varying breach locations, measures and use of outlet and drainage structures. Results 1. The most important factors which determine the flood duration are duration necessary to repair the breaches, the possibilities for drainage by gravity, the elevation and elevation variation in the area and the magnitude of the flood event. Flooding durations in the Netherlands vary between hours and about one year. 2. Adding flood duration as input to flood damage models adds a little extra accuracy. This is limited because flood duration is correlated with the water depth. With the current flood damage accuracy, incorporating flood duration is only useful for specific cost benefit analysis related to measures that aim to change the flood duration. Conclusions and recommendations Flood duration can be significant for large floods in low and endyked areas. In these cases flood duration can also have a significant impact on the damage. However, a complex economic model is necessary to quantify this. Therefore, flood duration can only reach its full value as an input, in combination with better economic modeling.

Fort Bay harbour is a small harbour, located at the South of the island of Saba. This island is part of the Netherlands Antilles and it is situated in the Caribbean Sea where hurricanes may occur several times a year. Since its construction in 1972, Fort Bay harbour has experienced several hurricanes. Unfortunately some of these hurricanes were responsible for damage to the harbour structures (mostly to the breakwaters). The damages caused by the most recent hurricane Lenny are still present. To improve this situation, local authorities of Saba have commissioned CEC (subsidiary company of Witteveen+ Bos) to produce a plan focused on a full restoration of the original harbour facilities in combination with an economically feasible protection against hurricane conditions. A basic element in this restoration plan is to identify what has caused the apparent damage to the Fort Bay harbour structures. The first part of the present study is meant to contribute to such an identification. From an overview of the history of Fort Bay harbour, an inventory is made of possible reasons why the harbour structures have not been able to withstand the conditions they have been exposed to. This analysis has a qualitative character. One of the items that have come forward in this analysis is a worsening of atmospheric and hydraulic conditions in the area around Saba. Looking at the damage caused by hurricanes that have occurred in the past few decades, there is a possibility that such adverse conditions show an increase in both frequency and intensity. Verification of this potential increase is the subject of the second (and also the last) part of the present study.

The aim of this thesis is to apply a reparation method, developed by the Pontificia Universidad Católica del Perú, on an adobe structure damaged by earthquake loading. This loading is applied with a shaking table test. Using these tests an ATENA- GiD model is made which is able to simulate the behavior of adobe houses under earthquake loading. A shaking table test is done to damage an adobe structure, after reparation, the structure is tested again and the test data of the original and repaired building is compared. The ATENA-GiD model is compared with the first shaking table test. The adobe model is made similar to earlier tests performed at the PUCP. The masonry is made with adobe blocks and mortar. The model is dried for 28 days and then subjected to an earthquake loading derived from the May, 1970 earthquake recorded in Lima. The tests consisted of 2 phases, the first phase with a maximum displacement of 30 mm and the second phase with a maximum displacement of 60 mm. Due to this loading, cracks became visible in the structure. These cracks are visible after a second phase, with a maximum displacement of 60 mm. To repair these cracks they are opened and cleaned with a drill and a hammer and pin. After opening, the cracks are repaired using two different methods, the “manual method” and the “silicone method”. The “manual method” consists of manually filling the cracks with the reparation mortar. The “silicone method” is a method where cracks are first covered with silicon and after hardening of the silicon, the reparation mortar is injected in the cracks. After 28 days drying, the structure is tested again with the same signal. Cracks are already visible in the first phase. In the second phase the structure partially collapsed. This is underlined by the data from the two tests. The natural frequency of the walls decreases during the first test. This implies that there is damage in the walls. After repair, the natural frequency goes up, but never reaches the original value. This implies the presence of non-visual damage. In the second test the roof detaches from the walls in an early stage of the test, this due to the non-visible damage that is not repaired and have weakened the structure. The detachment of the roof results in an structure with less stability and strength. Dynamic tests are expensive and time consuming, therefore It is important to find out what finite element software (FEM) can contribute to the research in adobe buildings in earthquake areas. In the recent past, FEM software was used on a very basic scale at the PUCP. With this thesis it is intended to explore the possibilities of using FEM software in the research of adobe buildings. This to further improve the research possibilities on adobe structures with respect to earthquake loading. The model for this thesis is made in ATENA-GiD. Due to the recent development of the scripts for this program, this study is one of the first trails for the program. Because of this, several bugs were detected. During the course of this thesis improvements have been made to the program due to close contact with the developers and the author. In spite of these improvements, the bugs in the program made it only possible to make a very basic model. This model has a coarse mesh and the material is modeled on a macro scale which means that the blocks, mortar and block-mortar interface are smeared out in the continuum. After repair the structure does not have the same behavior as the original test. Due to non visible damage that is not repaired, the structure loses strength and stability after the first test. Besides this, the repaired part is not as strong as the original masonry. Cracks between the longitudinal and transversal wall are very dangerous. The whole construction looses its stability and strength when these cracks are visible. ATENA-GiD can simulate the behavior in the elastic phase. The inelastic phase does not have similar results as with the PUCP tests. Improvements are made to ATENA-GiD throughout the course of this thesis. Due to lack of these improvements this model has a very coarse mesh, which was needed to reduce calculation time. Several updates in the program can now improve calculation time and therefore more time consuming models can be made, which will calculate the inelastic behavior better.

This study comprises the design of the reconstruction of the main breakwater of the Tripoli Harbour in Libya. Tripoli harbour is one of the oldest harbours of North Africa situated on the Southern coast of Mediterranean Sea. The harbour as it existed in 1972 was built at the beginning of this century and was protected by two main breakwaters. The original construction of these main breakwaters dates back to the Spaniards. The main breakwater on the North, known as the Spanish Mole, extended some 1900 m East North-East. A special feature of the harbour was the existence of a line of reefs north of the main breakwater about 100 m on the sea side, working as natural protection from wave attack. In the sixties, the increasing oil-based economic resources of Libya necessitated an expansion of the port facilities. Sir Bruce White, Wolfe Barry & Partners submitted a design of the breakwater locating the new breakwater some 100 m seaward from the Spanish Mole. The main breakwater was designed to be constructed in two stages; stage 1B, 2190 m long with a backfill (built 1972-1976, see Figure 2) and stage 2A, 2520 m long without any backfill (built 1974-1980). Significant wave heights of 4 and 4.5 m were adopted for the design of stages 1B and 2A respectively which were based on certain wave data available up to 1971 and 1975. Already during construction it became evident that the breakwater would not fulfil its design criteria. Two major storms in 1981 with a significant wave height of 9.2 m destroyed large parts of the breakwater. In deep-water sections (over 7m deep) almost all wave walls were broken and a large part of the 19-ton tetrapods damaged in the actual situation (see Figure 4). The direct hinterland of the breakwater is left at the mercy of overtopping water and spray. The two main roads on the landfill were completely eroded by overtopping and venting water.Netherlands Engineering Consultants (NEDECO) made a complete redesign of the breakwater in 1982 after the breakwater failure (see Figure 3).Meanwhile, during the last 16 years, extreme storms have further deteriorated the breakwater. Frequent nuisance of overtopping water and spray is no exception.The Harbour Authorities have asked for a complete evaluation and modification of the 1982 NEDECO design, because some criteria and boundary conditions have been changed significantly. In this study the new redesign criteria have been determined and based on these criteria a proposal for reconstruction has been worked out. The complete study of the Tripoli Breakwater reconstruction has been divided into four parts. These are: 1. Preliminary Investigations and Data Collection 2. Update Environmental Conditions 3. Preliminary Design 4. Optimization of the Reconstruction Design The approach used in the different sections is further described below and presented in a diagram.

Drainage- and storm runoff water is partly guided into the Right Main Canal of the Lam Pao irrigation project (Northeast Thailand). Measures are required to limit the chances on cross drainage flood damage. In the first reaches of the RMC (KM 0+000 - KM 37+130) there are 6 gated drainage outlet structures, but only one (at KM 4+893) is operational. It is found that an extra diversion discharge capacity of 13 cms is required. Therefore it is recommended to equip 3 of the existing drainage outlets (at KM 12+530, KM 17+140 and KM 20+440) with automatic Begemann gates. Outlet 5 (at KM 23+100) is close to a check structure and can simply be upgraded again with manually operated gates. It can be used in case supplementary spillway capacity is required. This study presents the hydraulic and structural design of the gates and substructure. It is found that relatively small gates can profitably be applied. Therefore the structures are each provided with 3 gates, each having a width of 1.00m. Sill elevation is 0.50m below full supply level.

Indirect Heat Induced Attachment and Detachment (HIAD) is a promising concept for gripping delicate tissues in ophthalmic surgery. However, the optimal settings of attaching to and detaching from delicate tissues are unknown. This study presents the effects of the instrument heating properties and initial contact force on the adhesion force, detachment success and thermal damage. An instrument prototype was developed to test attachment and detachment for different combinations of generated heat (3.5-20.0mJ) and pulse length (0.25-2.50ms). Thermal tissue damage was estimated with electro-thermal FEM simulations and histological analysis. The adhesion force depended strongly on the amount of generated heat and contact force. Pulse length played a minor role. Detachment success was determined by the maximum instrument temperature. Thermal tissue damage was strongly related to the amount of generated heat, the effect of pulse length was marginal. In RPE-choroid graft analysis, the RPE cells were not affected by heat. HIAD proved sensitive to heating characteristics and tissue properties. Nevertheless, this principle creates potential to build better performing tissue manipulators.

Bij de aanleg van de Noord/Zuid lijn in Amsterdam moet in de binnenstad een deel van het tracé worden gerealiseerd met behulp van de tunnelboormethode. Gezien de grondverplaatsingen en grondontspanning veroorzaakt door volumeverlies in en consolidatie van de grond tijdens het tunnelboorproces, worden problemen verwacht met betrekking tot (ongelijkmatige) zettingen van bebouwing. Gezien het feit dat paalfunderingen in Amsterdam veelvuldig langs het tracé wordt aangetroffen, moeten mitigerende maatregelen erop gericht zijn het draagvermogen van deze paalfundering te beschermen. Na het geven van algemene informatie betreffende het project Noord/Zuidlijn, de bodemgesteldheid in Amsterdam en enige aspecten van het boren van tunnels zowel in het algemeen als in Amsterdam, wordt een overzicht gegeven van de mogelijke mitigerende maatregelen. Hierbij wordt onderscheid gemaakt tussen: - het geheel of gedeeltelijk ondervangen van bestaande bebouwing, hetzij onder die bebouwing, hetzij via een constructie die gedeeltelijk daarnaast is gelegen; - grondverbetering via: * het kunstmatig bevriezen van de grond, als tijdelijke versteviging; * het injecteren (van chemicaliën) in de grond, als permanente versteviging; * het verdichten van grond (op paalpuntniveau), ter verhoging van de draagkracht; - het aanbrengen van een schermconstructle (dam-, combi-, diep, grout-wand). Bovendien wordt het gebruik van hoogwaardige monitoring system en beschouwd, die in combinatie met de bovenstaande methoden een op de omstandigheden toegesneden oplossing voor de zettingen kunnen vormen. De mitigerende maatregelen zijn zoveel mogelijk uiteengezet aan de hand van onder andere de volgende aspecten: doel, toepasbaarheid, eigenschappen van de toegepaste materialen, uitvoering, kosten, effectiviteit, voor- en nadelen en toepasbaarheid bij boortunnels. Aan de hand van de uiteenzetting van cases worden de praktische mogelijkheden van de verschillende methoden bekeken. De cases leveren vaak ook interessante combinaties van methoden op. Na het geven van het overzicht van mitigerende maatregelen is getracht te bepalen welke maatregelen voor universele toepassing geschikt zijn,waarbij al snel blijkt dat geschiktheid in hoge mate afhankelijk is van de situatie waarin de maatregel moet worden toegepast.

With an increasing population in the Netherlands, people started to live relatively close to the primary road network. This led to major noise hindrance issues. As a solution it was decided to apply porous asphalt surfaces on the primary road network. These types of surface layers have a relatively open structure compared to traditionally applied dense asphalt mixtures. Application of porous surfaces brings along their first major advantage: noise reduction. A second major advantage of porous asphalt layers is an increased safety during rainfall. Due to its open structure water is stored and moved horizontally within the layer which reduces splash and spray effects and thus increases the visibility of drivers during rainfall. On the other hand the major disadvantage of porous asphalt layers is durability. The decisive factor for the relative short lifetime of porous asphalt is the loss of aggregates from the surface, also known as ravelling. This type of distress leads to a rough surface and decreases the material’s noise reduction potential. Further on the loosened particles cause damage to cars. In the winter ravelling develops at a much higher speed. This results in totally damaged sections as was noticed during the winter of 2009/2010 in the Netherlands. In this research a recently developed Lifetime Optimization Tool for porous asphalt was used to find out why different sections of the primary road network showed this type of excessive damage. Therefore LOT required information about the load, geometry and the response of these failed porous asphalt sections. In this research eight different sections were studied. The required input for LOT was determined directly from these eight sections. The results showed that in the winter the main cause for this increase in damage is caused by the reduced relaxation potential of the mortar of the mixture. Further on the calculated performance of the eight different sections was compared with the observed performance during the winter of 2009/2010 and it was shown that they were in good agreement with each other. From this it was concluded that the Lifetime Optimization Tool is capable of explaining winter damage of porous asphalt concrete

One of the shortcomings of nonlocal damage models with a constant length scale parameter is the wrong prediction of damage initiation and propagation in correspondence of a strongly inhomogeneous strain field. This unphysical behavior can be corrected by considering an evolving length scale which is made a function of the stress state. Giry, Dufour and Mazars (2011) have recently proposed an approach, based on an integral nonlocal damage model, which solves the problem of incorrect initiation and propagation of damage as discussed by Simone et al. (2004). In this contribution, a similar approach is presented in a differential damage model, the gradient-enhanced damage model. The underlying idea, which is used to modify the governing equations, is explained. A new formulation of the finite element equations is derived, with attention to C0-continuity requirements. Representative examples will illustrate the performance of the proposed approach. Shortcomings of the model are pointed out and graphically explained using slight variations of the before-mentioned examples.

The research stage of this project is about the development of a toolkit for damage-assessment, to be used by leading people in smaller restoration-projects that lack the skills and knowledge to give proper leadership in the whole process. The subject in this case is salt-related damage in brick-masonry. In the design stage, a future use is sought for an historic 1900 fishery-warehouse in Vlaardingen. The aim is to make a flexible re-design while protecting historical values of the building and it's environment.

Gasses and fluids are transported via an extensive infrastructure of steel pipelines. In the design of pipeline systems the use of elbows (pipe bends) is important because their flexibility makes them able to sustain significant deformations. These bends can be subjected to permanent deformations due to various load combinations which can lead to progressive material damage. There are three stages commonly observed in ductile damage: void nucleation, growth and coalescence. When subjected to varying bending loads low cycle fatigue damage may occur. Within this research project Finite Element Analysis is used to simulate the response of pipeline bends. Two element types are implemented to model a pipe bend, the classical shell element and an efficient tube element (pipe elbow element), respectively. To predict the structural response when subjected to monotonic loading a damage model is implemented for both elements. When subjected to cyclic loading three phases can be identified. During the first few cycles the permanent deformation increases rapidly. After some cycles, the rate of permanent deformation stabilizes until the point of response degradation. In order to capture this response a new material model, based upon the afore mentioned model, is proposed. Experiments have indicated that this model is well suited to determine the point of material failure.

Recent tunnelling projects have received a great amount of media attention due to settlement induced damage. Due to the simplified approach of existing risk assessment methods, a new assessment system is in development, which can account for three-dimensional structural aspects of buildings. The aim of this study is to investigate the influence of the position and geometry of masonry buildings on the development of damage, while undergoing tunnelling induced settlements. In line with previous research, three-dimensional finite element analyses are used as a tool to perform a parametric study. A parametric study consists of an evaluation of the parameters position, aspect-ratio, grouping and orientation. The position parameter is divided into three characteristics: the sagging zone, a combined settlement profile and the hogging zone. The aspect-ratio parameter is also divided into three characteristics: shallow buildings, square buildings and deep buildings. The grouping effect parameter also distinguishes three characteristics: small and large isolated buildings and grouped buildings. The orientation parameter includes seven different increasing angles of the building main axis with respect to the tunnelling axis. The maximum measured crack width in the buildings gives input for a classification of damage, according the system of Burland et al. (1977). An average trend in the damage classification indicates the sensitivity to tunnelling induced settlements of the parameters. Both during and after tunnelling, a position of the building in the combined settlement profile appears to be the most sensitive to differential settlements. Buildings far away from the tunnelling axis generally obtain no more than slight damage. Structures with a low aspect-ratio seem on average to obtain equal amounts of damage as buildings with an aspect-ratio of 1. Structures with a higher aspect-ratio are less affected, both during and after tunnelling. Grouping of the buildings seems to be an influential parameter. Small isolated buildings obtain far less damage than large or grouped buildings. In relation to the numerical analyses, the empirical Limiting Tensile Strain Method (LTSM) seems to overestimate the damage for an isolated small building, but underestimate the damage in large or grouped buildings. For buildings in the sagging zone, a building with a low orientation angle is the least sensitive to differential settlement, while the maximum measured crack width increases by increasing the angle. The difference in maximum crack width can grow to a factor 3. A building in the combined settlement profile or in the hogging zone displays opposite behaviour. Cases with low orientation angles are the most susceptible to damage, while increasing the angle to 90 degrees lowers the maximum measured crack width. The difference in results can grow up to a factor 2.

Breakwaters are used for reducing wave height in harbours or divert sediment. One of the types of breakwaters is the rubble mound breakwater. These structures are constructed with smaller quarry rock as core and larger quarry rock as outer layer. For economical reasons, the design allows some damage to the armour layer. The amount of damage is objectively and quantitative determined by damage parameters. There are several different damage parameters which describe all different unique characteristics of the erosion hole. For a straight slope with a constant cross section, extensive research is executed for reliable design values of some of these parameters. For a 3D geometry such as a roundhead such design values are not formulated. This thesis is about roundhead model tests, executed at Deltares research institute. Four tests with increasing wave height are executed to eight identical roundheads. The roundheads weren’t repaired in between test so progressive damage occurred. The damage was analysed with the use of digital stereo photography (DSP), this high-resolution measurement technique creates a computer model of the physical model with a resolution of one mm. By subtracting the computer models of before and after a test, the erosion and deposition is accurately represented. The damage level is quantitatively determined by comparing different damage parameters. The compared parameters consider all different aspects of the erosion, the number of displaced stones (damage percentage Nd), the number of displaced stones per stone width (Nod), eroded area (van der Meer damage parameter S), nominal erosion length (L) & the nominal erosion depth (E). Before the results are being analysed, the data gathered from the DSP must be processed to smooth the individual stones but keep the erosion profile intact. The optimal smoothing process is based on a convolution or moving average principle. The size of the optimal smooth factor is two times the median nominal stone size (Dn50). The results show three erosion holes at the roundhead, the first erosion hole between 0~10° from the incident wave direction, the second between 60~70° from the incident wave direction and the third between 105~115° from the incident wave direction. The most damage was observed at the first and third erosion hole. The damage in the third erosion hole was slightly higher and more variable between the eight realizations compared with the first erosion hole. By comparing the different damage parameters it appears that only the erosion depth E, is representing the realizations correctly; the highest values in the third erosion hole with the largest deviation. Therefore design values of this damage parameter are proposed for roundheads with a slope of 1:2 and an armour layer thickness of two times Dn50. Initial damage: E = 0.2 ~ 0.3 Intermediate damage: E = 0.5 ~ 0.6 Failure: E = 1.0 ~ 1.1 Collapse: E = 1.5 ~ 1.6 To come to a generic damage parameter further research is necessary to validate the proposed design values for roundheads with different configurations, such as different slopes and different radius.

Decline in injectivity due to suspended solids in injected water is a wide spread phenomenon in water injection projects. Reliable prediction of injectivity through experiments and modeling is very essential under such circumstances. A model for predicting the injectivity during internal filtration taking into account particle dispersion, retention kinetics, nonlinear filtration, permeability reduction and viscosity functions was proposed. Subsequently, the analytical model for external filtration was coupled with the numerical model for internal filtration using the concept of transition time to predict the overall decline in injectivity. Core flood experiments using hematite suspensions for various particle concentrations (1-5 ppm) were conducted in Bentheim sandstone cores to quantify the injectivity. Simultaneously, X-ray CT scanning was performed under dynamic conditions to obtain deposition profiles along the core at different times. From microscopic analyses and visual observations, it was found that surface deposition in the porous medium and face plugging at the inlet of the core were responsible for decline in injectivity. A good agreement was obtained between the modeled and experimental results showing the validity of the retention function. Further, the effect of various parameters (particle concentration, number of grids etc.) on injectivity was investigated. Finally, the results from the study help the operators in planning and design of water management strategy for improved oil recovery projects.