Quay walls are an essential part of port infrastructure, providing diverse functionalities for the quay owner and users. In order to guarantee the structural safety of existing quay walls, owners might want to maintain their quay walls or decide to reassess their safety.

For various reasons, quay wall owners want to lower maintenance costs and postpone investments on their quay walls. Current methods for the reassessment of quay walls are partly depending on stochastic variables, which might lead to a rejection of the quay wall, while it is still safe to use them. Therefore, this research aims to develop an assessment method for existing quay walls based on observations of their real behaviour. This leads to the following research question:

How can existing quay walls in seaports be assessed using real-time data of their deformation behaviour?

In order to answer this question, a method was developed in this research for the assessment of quay walls based on their real behaviour. This method consists of 6 steps: .
1. The first step is the preparation of the data. All data is resampled to hourly values, in order to create a dataset with equal timestamps;
2. In the second step, Bayesian regression is used to create a prediction model of single measurement points on the quay wall;
3. The third step is to prepare the prediction models of the measurement points for the assessments;
4. The fourth step is the short term assessment of the quay wall. Real-time monitoring data is compared to the prediction model to assess if the quay wall shows safe deformation behaviour;
5. The fifth step is the assessment of the difference of the prediction models made for different measurement points on a single quay wall;
6. The sixth step is the assessment of the remaining capacity and the remaining lifetime of a quay wall.

To showcase the method and to verify and validate various aspects of the method, an example case was used. This case consists of four adjacent quay wall sections, that have been rejected by means of load/resistance based calculations. The developed assessment method was used to reassess these quay walls.

The results of this research show that the elastic behaviour of a quay wall is mainly influenced by the air and water temperature, the water level in the port, the groundwater level and direct loading. A prediction model created with Bayesian regression based on these causes was able to predict the quay wall behaviour accurate enough to use it for the assessments of the last three steps of the assessment method.

The application of the assessment method to the quay walls of the example case show that three of the four quay wall sections have enough resistance. One quay wall section shows questionable behaviour, which can be related to an early failure during the construction works.

The differences between the models of the different measurement points on the quay walls of the example case are all explainable by their location on the quay wall and the history of the quay wall. The most important explainer for the difference of the models of the different measurement points was the quay wall section on which the measurement points were located.

During the monitoring project, reinforcing measures were taken to try to reduce the ongoing quay wall deformation. The results of this research show that the measures were successful for most quay wall sections. Only at the section that was already showing questionable behaviour the situation worsened after the application of the reinforcing measures.

The conclusion of this research is that the six-step method explained above can be used to assess the deformation of a quay wall. Recommendations for future research are the broader application of the assessment method, the application of the assessment method with other monitoring techniques and the disentangling of the linear plastic trend in its deterministic causes. ... Read more

This report addresses the design of a quay wall on a steel slag subsoil. The reason for this study is the realisation of a wind turbine assembly port. Worldwide hydraulic structures are seldom made in these artificial soils. This steel slag material present in the project area complicates the construction of a quay. Is it possible to install foundation piles in this material? What environmental aspects need to be taken into consideration? Which quay wall type is most suitable for realising the port area?
The study starts by explaining the motivation behind the quay wall structure on this unconventional soil. The main reason for the need for wind assembly ports is to increase the wind turbine installation and maintenance capacity. The problem analysis explores the challenges associated with the steel slag materials, this leads to the problem statement and design objective. The problem can be summarised as follows: Despite the large experience in port developments and quay wall constructions, the ability to efficiently design a quay wall on a varying soil system like steel slag, is still considered complex. This leads to the goal of this thesis, which is to create a conceptual design of a quay wall on a steel slag subsoil at the location.
The design analysis aims to find the most efficient quay wall design, which is possible to construct and even take advantage of the presence of steel slag material to increase structural performance and stability. In the thesis approach, the steps taken to achieve the goals of the study are shown. The report proceeds with the development of a method in which the different characteristics of the steel slag material are examined.
The steel slag materials have some positive and negative effects compared to regular soils. The relatively high friction angle and high density can benefit the structure when applied at the right location.
One of the issues with using steel slag is the risk of environmental implications. When steel slags come in contact with air and water, heavy metals can leak out of the slag causing damage to the ecosystems and humans. The design solution aims to mitigate the environmental risks without exponentially increasing the costs.
A system analysis follows including an area, stakeholder and function analysis. This helped to illustrate the broader environment and requirements for the quay wall construction. The basis of design section outlines the starting points and boundary conditions whereafter the programme of requirements and evaluation criteria are defined. The report includes a functional and structural design.
After analysing potential alternatives for constructing a quay wall, the cofferdam variant was the most promising given the required bearing capacity, height and subsoil. The cofferdam design consists of two combi walls connected with tie rods at two levels. For stability, a grout anchor is connected to the backside of the combi wall. A low permeable environment was created because a clay layer is present between the two walls. The cofferdam dimensions were chosen so that most of the steel slag material would be enclosed between the combined walls. The residual volume of steel slag material is used as a fill material for the piles.
In the structural design, a detailed construction sequence and the design model were provided.
A PLAXIS 2D model based on Finite Element Method (FEM), was made for two cross-sections of the quay wall. Based on the outcome, the elements of the quay wall were verified and optimised. The installation method of the combi wall has a large impact on the cost. Results were analysed and risk-mitigation measures have been advised to provide a controlled construction. Various checks on stability, strength, stiffness and deformation were conducted to ensure this design meets the technical standards.
The validation of the design was then performed to check whether the design objective was adequately formulated and correctly translated into the requirements. As the client was Port of Amsterdam, the design was validated in correspondence with this company.
The report concludes with a discussion of design considerations and the implications of the design choices. Finally, the conclusions and recommendations section summarises the key outcomes of this report.
Based on the outcome of this report, it can be concluded that the construction of a safe and stable quay wall is possible with the right construction measures. It was recommended that further analysis of the environmental impact of the re-usage of steel slag material be conducted.

For further research, it was recommended to perform detailed calculations on the connection between the elements. In addition, a hydrological test could be performed to understand the flows of the rain and groundwater in this design. For the execution of the structure, it was recommended to perform an additional pile driving test with the driving shoes to prevent failure. The test results will show it this setup is suitable for the realisation of the quay wall. Additionally, it can provide extra certainty on the construction time, cost and knowledge. ... Read more

The aim of this research is to investigate which design method results in the best approximation of the deformations of a quay wall consisting of an anchored combined wall with relieving platform, looking at the elastoplastic method and the finite element method. The elastoplastic method is performed with the program D-Sheet Piling and the program Plaxis is used as a finite element method. Measurements on a quay wall in Eemshaven Groningen are used to analyze which design method results in the best approximation of the real deformation.

The D-Sheet model, after some adaptations in the calibration, gives a relative good approximation of the deformations, except for the deformations at the top. This deviation can be up to 113%.The calculation with Plaxis results in a better approximation of the deformation with a deviation from the measurement of only several mm. Comparing the results of both methods shows a large difference in top deformation. Two possible explanations for this large difference are investigated. The first explanation is that the modelling limitations of D-Sheet lead to different results. A simplified Plaxis model simulating these limitations results in a top displacement of 17 mm. Secondly, the difference in the input of the soil stiffness between both models is investigated by linking both stiffness parameters E and kh to each other using the relation of Ménard. A D-Sheet model with adjusted values for kh results in only a small change in the top deformation. The remaining differences in results are attributed to the difference in calculation method.

Several variations are performed in a sensitivity analysis to investigate to which extent different input parameters would have led to different results. This includes variations in phasing, modelling of the bearing piles, soil model, surcharge load, sea water level and soil parameters.
... Read more

The city of Amsterdam contains about 1600 bridges and 600 kilometres of quay walls. Of these walls, about 200 kilometres are of masonry walls placed on a timber floor and founded on timber piles. These quay walls are sometimes over 100 years old. Due to the increasing loads in the past century and the degrading of material properties in the masonry wall and timber elements, the quay walls are in bad shape. When designing a quay wall, a cross-sectional analysis is used to calculate the desired dimensions to withstand the loads. When this calculation is performed on a quay wall over a 100 years old, containing a failing pile foundation, the quay wall should fail. However, many of the quay walls under the condition of a partly failing foundation, are deforming, but still standing. During recent years, at 16 locations in Amsterdam, the risk of collapse appeared imminent, and emergency structures are put into place. Possible practical measures are removing trees on the quay walls, traffic limitations in the city centre and placing temporary struts and sheet piles to provide stability. Since the scale of the problem in Amsterdam is large, the time to renovate all the quay walls is lengthy. Therefore, there is a need for knowledge on the state of quay walls at the end of their life phase when partly failing. Different failure mechanisms occur, and various measures are developed to control those and provide (temporary) stability. This research answers the question: How can 2D analyses of quay walls, in multiple directions, under the condition of a partly failing foundation, provide insight into the hidden structural capacity within the masonry work? The study focuses on the severeness and scale of the foundation defects in the quay wall's cross-sectional and longitudinal direction. For the longitudinal models, the effects of the masonry material qualities are studied by using different material properties. Also examined is the effect of the failing foundation pile's post-peak behaviour, modelled as brittle and checked for plastic behaviour. Finally, the relevancy of the timber floor is studied for a stiff continuous floor and most notable, the full removal of the floor. To study this, two 2D regular plane stress, nonlinear elastic, finite element models are created in Diana FEA. The foundation piles are modelled as nonlinear elastic springs via a force-displacement diagram. The foundation piles' defects are modelled by assuming a smaller pile diameter, resulting in a weaker force-displacement diagram and larger displacements in the quay wall system. The foundation defects can be scaled over a small or big area by adapting multiple foundation piles over the length of the quay wall. The masonry's behaviour is researched by using a macro material model using smeared material properties for the brick and mortar, resulting in a continuous material. The material model used is the Total Strain Rotating Crack Model, which can be used in a 3D analysis of the quay wall system in future research. Finally, the interface between the timber floor and masonry is modelled using a coulomb friction interface criterion. This simulates the effects of the mortar layer connecting the timber floor and masonry work in a quay wall. The results conclude that analysing a foundation defect in the cross-sectional direction of the quay wall results in instability of the wall without further horizontal and vertical constraints to keep the quay wall in place. Modelling the pile foundation defects using a reduced pile diameter and consequently, a decreased force-displacement diagram as spring input provides the model with temporary stability. Ultimately, the cross-sectional analyses contribute little knowledge on residual strength and hidden structural capacity. Separately, the longitudinal model implements a vertical constraint in the masonry by using the bending capacities of the material. The results present an expected correlation between the scale of the foundation defects and the vertical displacements. Similar to the cross-sectional analyses, the reduced pile capacity of the foundation piles provides the model residual strength compared to the situation where the total failure of a timber pile is used. The timber foundation pile's failure mechanism needs to be researched in-depth since the results present a notable difference for crack patterns and force-displacement curvatures when modelled brittle or plastically. For brittle failure, a horizontal crack forms at the tip of the central, vertical crack, due to the abrupt enlargement in vertical displacement of the quay wall. The functionality of the timber floor in the longitudinal analyses presents itself when the crack patterns are analysed. The presence of the timber floor results in multiple smaller cracks instead of a single large crack when foundation defects of the quay wall system are analysed without a timber floor. It can be concluded that the masonry quality, most notably the tensile strength, affect the results significantly in terms of maximum values in the force-displacement diagrams and crack development. The material properties are based on Groningen masonry experiments, and it is recommended to perform experiments to the masonry quality of Amsterdam quay walls. Finally, the observed displacements related to the intervention points of the municipality conclude that foundation defects result in cracks for displacements below the marking points of 20 and 25 millimetres. For weaker masonry, the quay wall fails before the indication values. It is recommended to perform more measurements to the quay walls in Amsterdam and study the reliability of the intervention points. ... Read more

It is no secret that (asset)managers are currently dealing with a difficult task to maintain and improve the quality of their assets. The main reason for this urgency is the change of use and the end of lifespan of these assets. This is especially the case regarding the inner-city quay walls. These quay walls are usually owned and managed by local governments. The city of Amsterdam in particular has a tough task ahead of them. Approximately 200 km of quay wall need to be maintained or renewed of which the technical state is unknown. A vast majority of these inner-city quay walls are retaining walls on wooden piles. The absence of this information makes it extremely difficult for the asset owner, to determine the current technical state of their quay walls. The combination of limited information and time have shown in practice that quay walls can fail at any moment. To prevent this from happening a variety of intervention measures can be deployed to ‘extend’ the lifespan of the quay walls (short-term). Thereafter a systematic approach can be applied to rebuild or renovate these quay walls (long-term). However, the implementation of intervention measures is an overall complex task due to the densely built area and the stakeholders with divergent interests. This study provides an objective conceptual decision-making model to determine which intervention method is best suited for a particular location while considering the impact on the city, stakeholders and organizations. The research revealed six important topics which need to be incorporated in to the decision- making model. The topics were determined based on literature review, a case study and interviews. These six topics are: the critical cases (1), failure mechanisms (2), intervention measures (3), characteristics of the physical surrounding and the intervention measures (4), decision- making criteria (5) and lastly mitigation measures (6). Additionally, three decision-making moments are identified. ... Read more

Structures have to meet a particular level of safety. Therefore, in the European design codes (Eurocodes), three reliability classes (RC) are introduced based on the potential consequence of failure of the structure. For each of the RC a maximum allowable probability of failure is introduced, corresponding to a reliability index. In recent research by Roubos et al. (2018), it is suggested that the marginal costs of safety investments for quay walls is quite low. Therefore, it is questionable whether the current reliability classes and the corresponding set of partial factors, as defined in the Eurocodes and CUR 211, are functional for quay walls. This gave rise to the present study. This thesis investigates the relationship between the construction costs and the reliability index for two quay walls located in the Port of Rotterdam; 1) a double anchored combi-wall and 2) a combi-wall with a relieving platform.
In this study, more insight is acquired into the relationship between the construction costs and the reliability index of quay walls. Firstly, the two quay walls are designed semi-probabilistic in RC1, RC2 and RC3, using D-Sheet Piling for the double anchored combi-wall and using Plaxis 2D for the combi-wall with a relieving platform. Thereafter, the construction costs of these designs are calculated and compared. Besides that, the influence of the partial safety factors, which are defined in the Eurocodes and distinguish the reliability classes, on the construction costs is quantified. The same was done for the influence of three of the critical failure mechanisms; ‘passive resistance inadequate’, ‘sheet pile profile fails’ and ‘tension member anchorage fails’. For these failure mechanisms the reliability indices are estimated using the reliability analyses module of D-Sheet Piling, which is based on a probabilistic level II analysis, the First Order Reliability Method (FORM).
It appeared that the marginal costs of safety investments for both quay walls is relatively low, even significantly lower than suggested by Roubos et al. (2018). It followed that the differentiation in construction costs between the reliability classes is considerably less than the differentiation in construction costs between quay walls in practice. Therefore, it seems that the current reliability classes and the corresponding set of partial safety factors, as defined in the Eurocodes and CUR 211, are non-functional for quay walls. Besides that, it can be concluded that when designing a quay wall, the determination of the angle of internal friction of the soil strongly influences the construction costs, followed by the surface- and crane loads. The influence of the cohesion of the soil and the bollard load on the construction costs is very small. Furthermore, the influence of the failure mechanisms ‘passive resistance inadequate’ and ‘tension member anchorage fails’ on the construction costs of the double anchored combi-wall is relatively low. Therefore, it is suggested that the reliability index of the quay wall can be increased in a economically attractive manner by increasing the length of the tubular piles of the combi-wall or the steel sectional area of the anchor rod. Due to these influences, it can be economically beneficial to increase the target reliability index of the failure mechanism ‘passive resistance inadequate’ and decrease the target reliability index of ‘sheet pile profile fails’. ... Read more

The largest part of the European ports are engaged into addressing proactively environmental and societal issues in order to achieve an always more sustainable development. However, there are several sources that indicate that gaps and barriers exist which impede the sustainable development of many Mediterranean ports. In order to deal with the problems that are identified in ports and specifically in container terminals, which are closely related to their sustainable performance, a framework is developed. The creation of the Port Sustainability Assessment Framework (PSAF) allows the comparison of the current state of terminals with the desired state based on specific sustainability themes and consequently, evaluates their performance. Port sustainability is also approached by means of stakeholders' views and insights, throughout a questionnaire. The application of the framework in the case studies of Piraeus and Livorno, two container terminals of different sizes and challenges but both located in the Mediterranean area, proves that the concept of sustainability in the two container terminal case studies has not yet been embedded in the planning and operational phase as their sustainable performance is low. Another aspect that this master thesis addresses is the need to extend the Port of the Future Serious Game (PoFSG) in order to include in a realistic way port-city future developments and their potential impacts on the environment and the society, as well as to facilitate stakeholder engagement. Based on the results of the sustainability assessment, several weaknesses of the PoFSG are identified and tools are developed which can be useful for extending the PoFSG. The focus is mostly drawn upon two specific aspects: the scoring system of the measures' performance on “People, Planet and Profit” and the inclusion of relevant sustainability measures. Additionally, more general recommendations are made for the other aspects of the PoFSG. ... Read more

The initial masterplan of New Priok Development in Indonesia was developed in 2012 and is being updated to cater to new throughput demands. The masterplan of Phase I will be done as planned in which CT 1 was already operated since 2016 and CT 2 and CT 3 are in the final phase of land reclamation. In the new masterplan (2017), Phase II of the development will start in 2030 – onwards, depending on future conditions. However, whether the development of Phase II (continuation of Phase I) will be needed is still a question for the Port Authority. Hence, this study is about creating robust terminal masterplan of Phase II (2030 – onwards) which will remain functional under future uncertainties. The methodology/framework being discussed is Adaptive Port Planning (APP) which is considering flexibility design of port masterplan. Flexibility is very relevant for projects with high investment and surrounded by future uncertainties. In this study, considering the long-term project characteristics, the framework of Adaptive Port Planning (APP) Scenario-Based planning is developed. As a definition, the scenario-based approach helps to open up the perspective of the future condition of the port as a horizon of possibility and it gives chance to anticipate the vulnerabilities. Developing the scenarios are based on defined critical uncertainties using a 2x2 matrix approach. The economy (related to cargo performance) and environment are defined to be the axes of the matrix. The outcome is four plausible scenarios: Green Growth, Business As Usual, Moderate Expansion, and No Expansion. The next steps are examining these scenarios through some analysis to look at the characteristics and the promising industries in each scenario. In order to get the terminal needs in each scenario, traffic analysis in Port of Tanjung Priok is required; identifying the key influential cargos and commodities. There will also be a projection of containers based on defined scenarios. Producing the robust masterplan will lead us to a monitoring system and contingency planning for some highly relevant signposts. These signposts are the relevant future uncertainties which are not covered yet in the defined alternative layouts. Each of the signposts has to be analysed to prepare the contingency plans, mostly for IPC and some others for related stakeholders. In conclusion, this study proposes the adaptive framework of planning the terminal design for Phase II of New Priok, namely Adaptive Port Planning (APP) Scenario-Based Planning. It gives sequential work flow on designing future masterplan of the port, especially for the case of Phase II of New Priok. The alternative layouts and adaptive actions for IPC are some important outcomes of the framework. The port has to realize that uncertainties persevere and are very likely to influence the decision making for future layouts. Instead of ignoring uncertainties, the port needs to make contingency planning to deal with them. Hopefully, this study has benefits to make a robust terminal masterplan for Phase II of New Priok Development. ... Read more

Fiber-reinforcedplastic (FRP) is an upcoming material in the construction industry due tocharacteristic material properties such as its high resistance to corrosion andhigh strength to density ratio. Also, it is often claimed that structures fromFRP have lower life-cycle costs and eco burden compared to constructions madefrom steel, concrete, or wood; this can be attributed to the low amount ofrequired maintenance and longer life span of FRP. Therefore, FRP seems a verysuitable material in the harsh environments where hydraulic structures residecompared to conventional materials.

No actual commercial jetties, besidessmall pedestrian jetties, are yet constructed from FRP: knowledge regarding thepotential financial savings or the environmental impact of such jetties are notwell known. Also, specific consequences of constructing a jetty from FRP areunknown, as well the ability of FRP jetties to maintain their structuralcapabilities over their entire life-time. Therefore, this thesis investigatesthe feasibility of FRP jetties and judges whether FRP jetties are betteralternatives than jetties constructed fromtraditional materials. In the scope of this thesis, the research is narrowed down to comparing FRP withreinforce concrete (RC).

The main design challenge of FRP incivil engineering related structures is coping with the relatively lowstiffness of FRP, as this presumably determines the dimensions of thestructural elements and restrictions of the structure as a whole. Governingstructural safety criteria in steel and concrete are more often strengthrelated. The research rests on a case study of an RC jetty, which provides boundaryconditions and a program of requirements. An FRP jetty is designed whichcomplies with the structural criteria. These criteria were both extracted fromthe case study and provided by the CUR96, a Dutch design guideline for FRP incivil engineering practice. Most structural elements are designed from scratch:laminates are designed for the flanges and webs in a composite calculator namedeLamX2. The finite element method (FEM) software program SCIA Engineer is usedfor the structural analysis. One dimensional structural elements were firstvalidated before utilizing them in the FEM model. The pile properties anddimensions are based on contemporary literature and commercially availableproducts. The driveability of the FRP piles is researched by means of Wave EquationAnalysis of Piles (WEAP), for which the program AllwavePDP is utilized.Furthermore, sustainability aspects of both jetties are researched by means ofa Life Cycle Assessment (LCA). The LCA determines how much equivalentgreenhouse gases are expelled over the life-time of the jetties for a set ofimpact categories. These results are normalized by calculating the respectiveshadow costs for each impact category; this makes the total environmentalimpact of the structures comparable. The financial feasibility is the lastinvestigated topic; under various scenarios, life-cycle costs of both jettiesare investigated. The scenarios contained different variables such as estimatesof FRP raw material costs or assumed share of maintenance costs; end-of-lifecosts were not included in the analysis.

The structural analysis of the FRPjetty indicated that both Serviceability Limit State (SLS) criteria and UltimateLimit State criteria (ULS) determine the dimensions of the structural elementsand the jetty design in general. The most crucial parts are partially embeddedFRP piles, which are prone to buckling. Initially, the FRP piles in thedetailed design were to be installed to a depth of 13 meter below ground level,but the results from the WEAP indicated that the piles refused duringinstallation before reaching this level. An analysis indicated that drivingshorter piles to a depth of 8 meter is possible: at this depth, the piles donot refuse and have accumulated sufficient bearing capacity by shaft frictionto support the superstructure. The eco burden of the FRP jetty was foundsignificantly higher compared to the RC jetty: in the base case LCA, therelative difference is 365 percent higher for the FRP variant. After asensitivity analysis, the relative difference is still 59 percent higher when comparingthe best-case scenario of the FRP jetty with the worst-case scenario of the RCjetty. The RC jetty also performed better than the FRP jetty regardinglife-cycle costs in various considered scenarios. The relative difference inlife-cycle costs for the most favorable scenario of the FRP jetty is still 28 %higher compared to the life-cycle costs of the RC jetty.

Due to the poorer performance of theFRP jetty regarding the life-cycle costs and environmental burden, it isconcluded that FRP jetties, for the time being, are not better alternativesthan RC jetties. Regarding the type of jetty, the conclusion can begeneralized. The jetty is designed for the turnover of liquid bulk; imposed loadsare generally lower than loads on Ro-Ro, solid bulk, or container transfer jetties.It therefore seems unlikely that FRP does seem to be a better alternative forthose cases. Regarding the material choice, the conclusion cannot begeneralized. The FRP jetty was compared to an RC jetty. Jetties made from steelor wood are likely more vulnerable to degradation in harsh conditions. Thedurability properties of FRP might be more beneficial to the assessment of FRP jettiesin these cases. Certain future developments might affect the conclusion.Innovation in manufacturing techniques and an increase of market demand for FRPcould lower the price. Besides, biodegradable FRP materials are being developedwhich potentially may reduce the environmental burden of FRP.

 Keywords: FRP, composite design,hydraulic structures, jetty, pile driving, LCA, life-cycle costs ... Read more

Over the past years Fibre Reinforced Polymers, or FRP, have started making more of an appearance in civil engineering structures. They have the advantages that they are light-weight, do not corrode and theoretically require little maintenance during their lifespan. Originally they were used to construct reinforcement, cables and small bridges but more and more they are finding uses for larger scale structures. One of these newer applications is in lock gates.

Locks are structures which are responsible for enabling water based transport while also retaining high water where necessary and are critical links in the water defence system of a region. Their gates also have a relatively large risk of collision due to the amount of moving vessels passing through them. In order to safely construct these lock gates from FRP laminates it is important that their response to such collision loads is well understood. This is the focus of this study with the aim to construct a model to help better understand the collision scenario.

To make the theory concrete a case study is done on the lock gates of Sluis III which is situated in the Wilhelminakanaal in Tilburg. These gates are, at the time of writing, the largest FRP lock gates in the world. With the down stream gates being 13.9 by 6.3 meters. The event in which a Class III vessel collides with these gates will be examined in detail.

The collision is schematised as a one dimensional collision using a series of springs and dampers to obtain understanding of the general collision behaviour. From this model it is concluded that the application of a load from the ship’s engine or taking elastic deformations of the ships bow into account has negligible influence of the results (in the order of 2%), simplifying the calculations considerably. This simple model is later advanced in three ways: Two numerical finite element models are used to determine the structural response of the gate elements on a global and local scale and a more advanced analytical model is made to account for non-elastic deformation in the ship’s bow. The gate’s structure consists of multiple overlapping laminates which together form the skins of the gate. The numerical model is set up in two ways, one of which is used to determine the overall response of the gate element and the other to focus on the interlaminar resin layer in the skins. The results show that it is of importance to apply the load in a realistic manner as the results may vary widely depending on bow shape and point of impact. The approximation suggested in the Dutch codes in which the load is applied as a distributed load of a 0.5m2 areas proved to be inaccurate. For this reason a dynamic LS-Dyna calculation is run using a rigid model of the ships bow to apply the load. The outcome of this analysis shows minor damage to the gate over a large area around to point of impact, but the stresses remain under the failure limit of the laminates except for the internal flanges directly under the impact. These flanges will fail, but this will not threaten the water retention of the gate. The stresses in the resin layer also remain under their critical limit. It can be concluded that the gate satisfies the requirements but significant repairs will be necessary to restore it to a fully operational state.

The expanded analytical model is based on the fact that the force between the bow and the gate is larger than the failure load of the bow itself. The failure which will then take place will dissipate large portions of energy (in the order of 50%) making the current approach, in which this does not take place, highly conservative. The model suggested here is a segmented failure model in which parts of the ship bow fail completely once their failure load in reached. The results of this model are dependent on a series of inputs based on the ships structure and the damping during collision, but for all input values within their expected regions it shows a significant reduction in the amount of the energy that must be retained by the gate as well as a decreased sensitivity to the, hard to predict, damping factor. This model shows potential to reduce material usage for lock gates in which collision
are considered governing. With further refinement this model could be used during the design of future lock gates to come to a cheaper design. Experimental data would serve an important purpose during this refinement. ... Read more

The construction method of an overturning caisson is reconsidered. This particular self-floating caisson was applied for several caisson quay wall projects over a century ago. After the year 1914, the design was abandoned. After this time, rectangular caissons became more economical due to higher qualities, simplified formwork and easier transport. However, the caisson geometry allows efficient material use and a relatively low draught during transport. When the concept is considered for current quay wall projects, these benefits are still present. However, the magnitude of these benefits reduced significantly. When other aspects, such as construction technologies are included, the remaining economic benefits are estimated to become negligible. The economic feasibility of an overturning caisson could therefore not be demonstrated.

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When a quay wall does not meet the safety requirements it has to be replaced by a new quay wall. During the entire replacement project many stakeholders are affected. This can lead to resistance against the project. Resistance can be expected when the interests of the stakeholders are not (sufficiently) integrated in the design or construction method of the replacing quay wall. The high density of stakeholders in urban areas increases the probability that stakeholders will resist against the project. In Amsterdam the lead time for replacing a quay wall is up to five years this lead time accounts for the time from the decision to replace the quay wall until the realization of the new quay wall. One of the reasons for the long duration of the replacement projects is the time invested in dealing with the resistance of stakeholders. While the construction method of the new quay wall has influence on the reaction of the stakeholders, the reactions of the stakeholders on the other hand may influence the construction method. Therefore, in order to reduce the lead time for replacing a quay wall, an optimum between the construction method and the reaction of stakeholders is expedient. In order to minimize the resistance of the stakeholders it is advisable to take the interests of the stakeholders into account. The objective of the present research has been to develop a method to determine the construction method that will most be in accordance with the interests of the stakeholders, in order to possibly minimize the resistance produced by the stakeholders. C&S-matrix In this research, a method called “construction stakeholder matrix” (C&S-matrix) was constructed. This matrix connects the stakeholders and the construction method directly, by comparing the extent to which different construction methods are in accordance with the stakes of the stakeholders. Thereby, the matrix takes into account the influence of different stakeholders on the outcome of the project. The outcome of the matrix is a numerical value: the lower the number, the more resistance can be expected. The C&S-matrix is applied on a case of the Prisengracht in Amsterdam, four types of urban quay walls were selected. The outcome of the matrix is that the combined wall with inclined piles will result in the least amount of resistance produced by stakeholders. The C&S-matrix is a useful method to determine which construction method produces the least resistance. Since the output is numerical value it enables that the construction methods and the expected resistance can be compared, which makes this method unique. The effectiveness of the C&S-matrix mainly depends on the stakeholder analysis, it requires that all the stakeholders with their interest are identified and that the power-vs-interest grid resembles the actual power and interest of the stakeholders. This method predicts which stakeholders will most likely resist, this gives information for other measures to reduce this resistance for example compensation. ... Read more