This report includes all the research conducted during the last phase of the Master of Science Building Engineering within the faculty of Civil Engineering. The main aim is to form a strategy for designing demountable unitized curtain walls; one that could actually be used in practice by future engineers and architects. This is why this graduation project includes an application on 4 chosen adaptive concepts. Having already been applied in a comparison study of these quite complicated and costly designs, this framework can provide one extra consideration that will be critical in the near future at the very early stages of designing a building: the Design for Disassembly.

Human-induced rhythmic loading is an increasingly critical aspect in the design process of civil engineering structures such as sports stadiums and floors accommodating gym and aerobic classes. There are two main reasons for this trend. First, structures are becoming more slender with improvements in materials and construction techniques and modern trends in architectural designs. And second, crowds are getting livelier than previously was the case, their activities can become better synchronized due to the presence of various auditory and visual stimuli at above mentioned events. In recent years there is also a growing discussion on the strength and stability of event structures. A very common type of structure is an event deck structure. Visitors gather on top of these decks during festivals and in some cases festival organizers place bars underneath them to efficiently use the structure. Personnel working in these bars experience the movement of the structure due to a dancing crowd and tend to feel uncomfortable. Engineers at Tentech are aware of this phenomenon through contacts with clients. Nowadays, in the Netherlands, event deck structures are designed to withstand a vertical static load of 5 $kN/m^2$, prescribed by Dutch design codes. The amplitude of this static load is based on a dense static crowd. But according to existing literature, a synchronically jumping crowd can cause a vertical load which far exceeds the design load prescribed by design codes. This provides a reason to further investigate the extreme load case of a synchronically jumping crowd on an event deck structure. A missing element in the standard design of structures subjected to a synchronically jumping crowd is the consideration of dynamic interaction between human and structure. In this research the focus is on how human-structure interaction (HSI) can influence the human-induced loading and the internal stresses caused by that loading in the structure. This is done by building a 3D finite element model in Abaqus. A 3D finite element model is used to easily vary in the position of a jumper on the structure. Modelling group effects such as the coordination factor is also easier when using a 3D model. And in the case of an event deck structure a 3D model will result in more detailed results compared to 2D models because mechanical properties of an event deck can vary over the third dimension. A mass-spring system is suggested to represent a jumping person. To simulate a synchronically jumping crowd, multiple mass-spring systems are used. By assigning an initial velocity to the mass in the mass-spring system, it is possible to simulate a similar mechanism as a jumping person colliding with a structure. By analysing the force in the spring over time it is possible to draw conclusions on the influence of human-structure interaction on the impact peak force. And by comparing the impact forces with the reaction forces which are measured at the base of the structure, the effects of structural vibrations on the internal stresses are determined. It is found that taking HSI into account does influence the impact peak force and the internal stresses of the structure. But for an event deck structure with a natural frequency of 20 Hz or higher, this only accounts for an individually jumping person. It is found that the more people jump on a structure, the less significant the effect of HSI will be, even when a crowd tries to jump synchronically. This is caused by the natural time lag between each jumping person.

Additive manufacturing and 3D printing are rapidly developing digital fabrication techniques. After the first steps in printing of metals and plastics have been made, research from various groups around the world is now also focusing on printing in concrete and moving to larger scales. Using this technique it will be possible to create customised concrete designs in one go at low costs and high construction speeds. Additionally, this new technology will provide opportunities to create more efficient structures. Structures can already be optimised in the early stages of the design for weight and structural performance, but the resulting optimised structures are often difficult to manufacture due to their shape. Additive manufacturing can be the key to make this possible without high costs for moulds and labour. This thesis will present a novel methodology to include material and manufacturing constraints of 3D printed concrete in the optimisation process. The study examines the possibility to optimise concrete structures in the design phase. In order to save material and thus create more sustainable and more cost efficient structures, a topology optimisation tool has been created specifically for 3D printed concrete. Traditional topology optimisation methods consider isotropic and linear elastic material and will not necessarily produce realisable and reliable optimised structures. In the algorithm presented constraints of the printing process and material properties from physical testing of this layered material are both considered in the optimisation. By adopting this methodology more realistic and feasible optimal concrete structures can be designed.

An exploration into the stability of 3D printed thin-walled concrete elements during manufacturing is presented. The failure mechanisms, material parameters and analysis methods are presented. Self-buckling is the dominant failure mechanism, where the Young's modulus plays an important role. Material experiments to assess the Young's modulus are performed and presented. Predictive analysis methods to evaluate the printability of objects are discussed, where finite element modelling and the mechanistic model of Suiker are compared.

This master's graduation project researches the potential of upcycling waste glass into glass-ceramic components through casting techniques and thermal treatments. To explore its potential and possibilities, the process of crystallization, the material glass-ceramic and influencing parameters are studied at first. A glass-ceramic is a glassy yet crystalline material consisting of inorganic and non-metallic compounds. A glass-ceramic can be produced through different controlled crystallization methods, whereas in this research heat treatment of casted components is applied. Upon heat treatment, crystallization occurs when the right temperatures are applied for the two-steps in crystallization; nucleation and crystal growth. Crystallization may occur spontaneously or along preferential sites, whereas this research makes use of the latter. Many parameters affect the crystallization process, whereas this research only focusses on glass composition, temperature and dwell time. The parameters are set through literature study and trial and error of melting experiments. This research focusses on the crystallization of soda-lime-silica bottle glass, the results of each melting experiment show the effect of the parameters. Each glass from another manufacturing has another glass composition. The amounts of glass formers, modifiers and fluxes are various, resulting in diverse temperature curves and thus diverse melting temperatures and crystallization temperatures. Through the melting experiments are noticeable that the applied melting temperature were of bigger influence than the crystallization temperature. A melting temperature too low resulted in an undesired fused sample, while a too high melting temperature resulted in no or little preferential sites for crystallization to occur. Through the results of the splitting experiment the mechanical characteristics could be observed, which are fracture toughness and fracture behaviour in this research. The fracture toughness seems better of samples with a higher quality crystal polymorph or with a higher amount of crystallinity or high amounts of glassy phases, whereby the material acts as one material upon loading rather than as a composite. While for samples with little and unconnected crystallization it does not seem to benefit its fracture toughness. The fracture propagation through glassy and crystalline phases is very different. A fracture propagation through a glassy phase is conchoidal, while the fracture propagation in the crystalline phase follows the crystalline structure, reaching its extremities or can be conchoidal, depending on the crystal polymorph. Observable from the fracture propagation from glassy to crystalline and from crystalline back to glassy is the discontinuity. The crystal or crystalline surface acts like an obstacle once the failure propagation reaches from the glassy phase. The failure does propagate but once it continues over to the glassy phase again, a change in energy and direction is noticeable. All by all, there do is potential in upcycling waste glass into structural cast glass-ceramic components. Crystallization does influence the fracture toughness and fracture behaviour in a cast glass-ceramic component, but the effect is highly dependent on the amount and distribution of glassy and crystalline phases.

Over the last years the critical state of existing quay wall structures have gained a lot of concern. With the focus on urban quay walls in Amsterdam, a lot of aspects could play a role which limit the possibilities for both the design and the construction. The focus in this research is placed at the structural efficiency of the design for renovation projects. By using a parametric approach (with Grasshopper/Rhino) in the preliminary design phase, a design solution with the lowest use of material can be found. From the total of embankment within the management of the municipality, a scope has been defined focusing on the most critical quays with respect to the limited design space and high expected loads. Within the assumptions made, the developed parametric tool can be used to indicate an efficient design solution for which the positioning of the piles, the diameter of the piles and the thickness of the floor follow from the location-dependent input. The indication of the effect of geometrical properties with respect to the defined objective (minimizing the material use) could help in the consideration of the design requirements. Apart from indicating the savings that can be made on the material use by improving the structural efficiency of urban quay wall design, this research also contributes to proof of the power to be found in a parametric approach. The repetitive character in especially large-scale assignments as the renovation of Amsterdam's quay walls makes it a highly appropriate method.

The buildings construction industry is demanded to reduce its ecological footprint to mitigate its contribution to climate change. In this context, a novel sustainable design strategy for the reuse of timber was developed in this Master thesis. The design strategy focuses on the utilization of the material “reclaimed timber” (RT) in the structural system “reciprocal frame” (RF). RT is timber which is harvested from the load bearing structure of dismantled buildings. Large quantities of RT are currently fixed in the building stock. RFs are a family of structures that boast with a rich variety of forms and diverse functions. The utilization of RT in RFs is favorable because RT items which are relatively short can span distances longer than their length when combined with RFs. To inform the development of the design strategy a literature review on both RT and RFs was conducted. These theoretical studies were supplemented with more practical methods of investigation: RT was inspected first-hand during a visit of a salvage yard that stores RT. Throughout the project physical modeling was used as tool to explore and illustrate the characteristics of RFs. Moreover, during a three-day workshop in which a RF canopy structure from RT was built, important design aspects of RFs were investigated. This first part of the research concluded with describing the state-of-the art of the structural utilization of RT and providing a comprehensive overview of the structural design with RFs. Key findings of the theoretical and practical studies on both RT and RFs were that the limited stock of available RT items and the geometric complexity of RFs are the two major problems when designing a RF with RT. To solve the two problems a novel RT database configuration that archives the properties of specific RT items was developed. This RT database was applied in conjunction with a novel bottom-up geometry generation model for Rainbow RFs. The Rainbow RF was identified as advantageous for the combination with RT. It can be used to generate expressive spatial assemblies with a relatively low geometric complexity and a high degree of regularity. From a structural perspective the Rainbow RF has the benefit of efficiently transferring axial forces, which reduces the bending action that is typical for RF. Moreover, it achieves flexural rigidity without using expensive moment resistant joints. The key findings were integrated to form a preliminary design strategy. In a case study the preliminary strategy was used to design a RT RF for a railway station canopy that spans an area of 14.0 m x 27.0 m. The RT stock of the case study was defined by a database that is comprised of 30 stacks of RT items. Based on the material stock 118 geometric design proposals were generated using the bottom-up model. Three of the proposals were developed into safe structural designs. The three safe structural designs demonstrate that the RT items compensate their low strength grade with their relatively large cross-sections. Based on a discussion of the case study’s design process, a complete design strategy for the structural utilization of RT in RF structures is derived. In the first design phase the shape of the building and the flow of forces through the structure are established. The material stock is defined using the novel RT database configuration. For each RT stack multiple geometric design proposals are developed with the bottom-up model in design phase 3. The bottom-up model is set up in “Grasshopper 3D” and “Python”. For the fourth phase, a versatile algorithm is programmed that automates the structural design to a large degree. This enables to assess many geometric design proposals with considerable accuracy in a short time. The Structural Design concludes with a complete design of the RF structure. The structural design algorithm is also programmed in Grasshopper 3D and Python, the plug-in “Karamba3D” is used for finite-element analyses. The Detail Design rounds the design strategy off by detailing the structure’s joints.

Steel trusses are the preferred structures when large distances are required to span due to its lightweight, the reduced deflection and its load bearing capacity. Although nowadays with the help of computational tools more efficient designs can be achieved, the geometrical shape of trusses has barely changed. This is mainly due to the ease of the required structural calculations and due to the available standard manufacturing and assembly procedures. Although a standard shape could be seen as an advantage, studies suggest that the relationship between the efficient use of material and design rationalization is not balanced, leading to design-overcapacity of the structure. The use of optimization procedures provides new opportunities to engineers. New design solutions and near-optimal structures can be achieved when implementing optimization processes. Optimization processes could generate economical alternatives in terms of weight reduction. Despite optimization techniques are becoming increasingly available, optimized structures are not commonly used in real practice due to the complex configuration an optimized structure might have, especially when using layout optimization. Due to the non-conventional node-members configuration, realizing these optimized trusses in real practice with conventional joining mechanisms, such as bolted and welded connections, will probably lead to complex designs and higher costs. Therefore, innovative joining technologies are required to be implemented. Snap-fit connections are widely used connecting mechanism for joining plastic components. Due to its simplicity and efficiency while connecting two or more elements together are suitable for different applications. Despite it is not commonly used in the building industry and it is frequently used on small scale applications, the principle based on snap-fit connections could be used to connect the structural members of optimized trusses. First, a literature study provides a clear understanding of truss structures, focusing mainly on the importance of their joints. Structural optimization is also discussed, paying special attention on a new layout-optimization approach, which is based on two steps: first, the less-weight possible layout is obtained (the benchmark) without taking into account any buildable considerations. The second step consists on rationalizing the benchmark contemplating practical and buildable restrictions. Finally, a representative case-study steel truss is presented. The second part of this research explores the structural design and the optimization procedure applied on the case-study truss. Here the layout optimization approach is applied using Peregrine (plugin for Grasshopper). After an optimized layout is generated, it is design structurally using Karamba3D. Finally, the case-study truss and the optimized truss are compared. To explore the opportunity of implementing optimized trusses in practice, the conceptual design of an innovative joint based on snap-fit connections is developed. A representative internal node from the optimized truss is chosen and based on a general concept, three design concepts are created. Extensive Finite Element (FE) analyses are carried out to study the structural behavior of the innovative joint during three main phases. All FE analysis were performed using the FE software Abaqus. To conclude, this research project is an exploratory feasibility study of the use of steel snap-fit joints as internal nodes for optimized steel trusses.

The construction sector contributes to a significant portion of global energy consumption, CO2 emissions and the use of material resources. As climate change escalates with rapidly increasing temperatures, more extreme weather patterns and rising sea levels, an urge to reduce the environmental impact is evident. A discrepancy is visible between early structural design and the required information for performing an environmental assessment. The first phase of design is an excellent time to steer the design to be more sustainable. However, today's procedures, involving LCA, only provides feedback at a later phase. This is due to the required highly detailed information for performing this complex and time consuming assessment. An assessment tool that supports the conceptual design would help to reduce the environmental impact. The research project aims to show the feasibility of sustainability feedback using analytical methods on stored building data in early design. It provides LCA feedback in the conceptual design phase. A proof-of-concept is developed on industrial warehouses showcasing the functionality of the framework. Lacking the required building data and LCA scoring, a fully automated script is created with the parametric plugin Grasshopper, to generate the warehouse data. Due to time constrains and performance limitations, the scope was limited to the structural system of beams, columns, purlins and braces. The script randomly iterates over its parameter domain, automatically changing the geometry, performing a structural optimisation and calculating the LCA. This assessment is limited to a cradle-to-gate system boundary. Data is automatically written to a web-hosted database on the Packhunt.io platform of White Lioness technologies. The feedback is based on retrieving data from the database, applying a performance based algorithm, and finding the parameter that decreases the LCA score the most. Results are visualised to the user. The result is the Interactive Design Assist (IDA) prototype that suggests parameters to the engineer in reducing the LCA score. This information provides guidance in the conceptual design phase on structural design of industrial warehouses. It demonstrates the large potential of reusing 'knowledge' inside the design process to improve building designs.

This research investigates if confining rubble stone masonry by timber bands and columns increases resistance against earthquake loads, by performing a number of numerical analyses in the finite element software program Diana. In order to establish a reliable model, the input parameters are investigated by means of a literature study and sensitivity study. Additionally, the numerical model is validated by comparing the results to an analytical study. From the analytical study it is determined that the failure mechanisms are correctly estimated by the numerical analysis. However, differences between the values of ultimate strength and ductility were observed. The effect of the confinement is investigated by a pushover analysis on a shear wall with two different masonry tensile strengths: ft = 0.01 N/mm2 and ft = 0.03 N/mm2. These values are selected to show how such a small difference in tensile strength results in a different failure mechanism of the wall, and therefore results in a vastly different displacement capacity and ultimate strength. Additionally, a shear wall with and without a window opening is studied. If the building is constructed with extremely low-strength masonry (ft = 0.01 N/mm2), the timber frame confinement will increase the resistance of the wall (with or without window opening) against the pushover load. If the building is constructed with masonry having a tensile strength of 0.03 N/mm2 or higher, the confinement has a negative impact on the ductility of the closed wall. For the wall with window opening the confinement triples its ultimate strength. Weather a strong or a ductile structure is more desirable, depends on the demand with respect to the seismic spectrum. If the ground motion demands a strong structure, it is advised to confine the masonry with a timber frame consisting of four timber bands, and columns at each wall junction. The design of the timber frame as recommended by the Nepali building codes is determined to not be sufficient and must be altered in order to provide this positive impact on the structure’s resistance. Firstly, the columns must be placed at both sides of the band, instead of on the inner side only, to avoid eccentric loads on the bands. Secondly, the cross-sectional dimensions of the bands and columns must be increased avoid failure of the connections and splitting of the timber. Taking these aspects into account, a new design for the confinement method is presented in this study. The limitations of the conclusions of this research follow from the investigation of a single, in-plane wall only. One of the goals of the use of bands is to improve the box behaviour, for which the out-of-plane performance must be investigated. Moreover, an analysis on a three-dimensional structure is needed to fully answer the research question. In a three-dimensional study, the closed walls and walls with opening give a combined response to the load, therefore, the advantages and disadvantages of the confinement are combined as well.

The construction, operation and maintenance of buildings consume more than 40% of primary energy in most countries. Out of this 40%, a large portion is related to the operational phase involving heat losses through a buildings envelope. To reduce this loss, several materials have been developed to reduce the thermal transmittance through a façade, even though they carry a heavy environmental burden. Furthermore, the unregulated and rapid expansion of urban environments led to a considerable amount of problems. Among them, the urban heat island effect demands special attention as it has been responsible for an increase of the energy consumption to higher mortality rates. In part, the use of materials with high thermal admittance is responsible for these effects. Vertical green systems have shown to be a potential solution to improve, among others, the thermal demands of buildings and to mitigate the urban heat island effect. However, due to the uncertainty associated with their design process and operation, the implementation of vegetation as a construction material in an urban setting is often overlooked. Therefore, an in-depth study of their performance under different configurations and climate conditions is needed. The optimization study was based on the parametrization of a green façade and a living wall system which aimed to identify their response under variable initial conditions. A analysis of the essential parameters in the vegetation model was performed. Consequently, the leaf area index showed the highest effect, followed by the substrate thickness, leaf angle distribution, leaf surface albedo and finally by the moisture content of the substrate layer. Furthermore, a state-of-the-art computational work flow was developed through the integration of ENVI_met, Rhino/Grasshopper and modeFRONTIER, in combination with Python 3 scripting, to evaluate the performance of vertical greenery systems. The evaluation focused on the heat transmission through the façade of a single building, in comparison to a reference model. The work flow allowed the study of the impact of each parameter in the behavior of the system and led to the development of several design guidelines. The optimized result was tested in an urban setting to evaluate its potential as a mitigation strategy for the urban heat island effect. The largest reduction in thermal transmission took place in equatorial, fully humid climate due to the low vapor pressure deficit; while the lowest in a temperate climate during winter conditions, suggesting the lower efficiency of the systems under cold weather. Furthermore, living wall systems have a significantly higher performance in comparison to green façades. On the other hand, the latent heat release associated with the evapotranspiration process has a strong correlation with the leaf area index, given the simultaneous action of the aerodynamic and bulk surface resistance. The optimized configuration of the vegetation was then derived based partly on this correlation. Moreover, the leaf angle distribution displayed a high correlation with the solar zenith angle and the leaf surface albedo with the intensity of the solar radiation and the ambient temperature. Additionally, among the substrate properties, the substrate thickness indicated a large potential in reducing heat transmission. The effects of vertical green systems in an urban setting suggested an improvement of the environmental conditions. While the leaf area index is directly related to the decrease of wind speed and evaporative cooling, the leaf surface albedo influenced the amount of reflected shortwave radiation in a façade. Furthermore, the highest cooling potential was observed in desert climates as a result of the high vapor pressure deficit with temperature drops of up to 0.25 C. The outcome of this research indicates that an optimized vertical greenery system is a suitable replacement for artificial insulating materials as a passive alternative to reduce energy demands in buildings. Indicating a decrease in heat transmission from 8% to 50% of the original heat flux. Furthermore, the findings of the urban study suggests that a decrease in the ambient temperature and an overall reduction of the negative impacts related to the urban heat island effect is possible.

The objective of this research is to design and evaluate a new type of rolling gate for the Western lock (Westsluis) in Terneuzen, for which all sensitive and heavily loaded mechanical parts are both easily accessible and located above water. Having all mechanical parts above water not only makes them easier to inspect and maintain, but it also makes them less prone to fouling or obstruction by debris. In this way, the risk of premature gate failure due to failure of wheels/rails is expected to be lower, increasing the overall availability during the lifetime of the lock. Six variants are designed and evaluated using a qualitative Multi Criteria Analysis (MCA) and the Cantilever rolling gate is evaluated most feasible. The Cantilever rolling gate concept is a system in which all the rolling supports are located on an extension to the side of the gate. The gate is balanced by a counterweight and in a way 'hangs' in the gate chamber. The carriages are connected to the gate by hinges, which ensure the perpendicular horizontal movement of the gate in closed position to seal the lock against rubber profiles on the sill, gate chamber and recess. Subsequently the Cantilever rolling gate is further elaborated at the case study location by means of structural calculations. The focus of the design calculations is on the load balance of the gate and supports in the longitudinal direction. To minimise the required extension of the gate chamber, the added cantilever length is kept as short as possible. To find the most optimal cantilever length, limits are defined regarding the minimum required force acting downwards on the carriages to maintain equilibrium and the maximum design capacities of the wheels and rails with respect to strength and fatigue. Based on the performed calculations, the most optimal Cantilever rolling gate design for the Western lock in Terneuzen has the following properties; an added cantilever part with a length of 16.6 meters; a cantilever truss structure constructed of Circular Hollow Sections (69 t); a counterweight directly below the back carriage (1083 t); an 8-wheel front carriage and a 4-wheel back carriage. The added cantilever structure of 16.6 m extends the gate part of 44.6 m by 37%. The designed cantilever rolling gate fits at the location of the case study, but the lock chamber and rails should be lengthened by 16.6 m to fit the extended gate. Based on this research it is expected that the concept of a Cantilever rolling gate is technically possible. However, it is not yet certain whether the Cantilever rolling gate will also be feasible in practice. Some additional development is still required before the design can be considered fully technically feasible. For example, it is important that the horizontal force transmission and guidance is further evaluated. It is also recommended to calculate the actual availability and determine whether the difference in availability between the Cantilever rolling gate and the conventional rolling gate outweighs the cost.

In the future most of us will be living in cities and due to climate change global average temperatures are expected to rise. As a result of the urban heat island effect, the temperature in cities can be up to 7 C higher than in the surrounding rural area. Higher air temperatures are not only uncomfortable, but also unhealthy especially for vulnerable groups such as elderly people. So there lies a challenge in making our cities adapted to climate change. One of the strategies of climate adaptation is the implementation of greenery. However, due to space constraints it is not always possible to plan urban parks. A relatively new trend is the integration of greenery into buildings. A significant amount of research has already been done on green roofs and green facades, but there is not a lot of knowledge available on green balconies. Vertical forests - buildings with full-sized trees on the balconies - can improve the local microclimate in the city by solar shading, evapotranspiration and wind flow change. By modelling the heat and moisture transfer of trees on balconies within the urban context, this research aims to evaluate the cooling benefits of green balconies on the local microclimate.

The increased loading and decreasing strength of historical quay walls calls for remedyand has drawn the attention of many Dutch municipalities, Rotterdam being oneof those. In order to set up proper assessment methods that result in an economicaland ecological policy for renovation or replacement of these structures the Port of Rotterdamhas asked Delft University of Technology to assist them. This thesis focusses onthe elements perhaps most prone to decay and hardest to inspect: the timber foundationsimplemented in quay walls with relieving platforms from the late 19th and early20th century. The main research question of this thesis is What is the (remaining) capacityof the timber foundation of a quay wall with relieving platform? and focusses onthe Maaskade case. The aim is the provision of a structural analysis and appointmentof weakspots on a representative quay section build-up using measured material characteristics.This quay has partially collapsed and has been replaced as of May 2020. 45Timber piles from the site have been investigated in the Rotterdam harbour to derivedensity and (dynamic) Young’s modulus measured by a Timber Grader MTG. A selectionof these piles was then further tested in pieces (21) at the TU Delft structural laboratory(Stevin II) to derive the Young’s modulus and compressive strength. Using the correlationfound between the compressive strength parallel to the fibre ( fc,0) and the dynamicYoung’s modulus parallel to the fibre (E0) the compressive strength values of the entire45 pile group have been derived. This results in fc,0,k = 12.64 MPa and E0,mean = 11.3GPa under 50% moisture content, the saturated state the wood is expected to be in inthe quay. The resulting design strength fc,0,d = 10.7MPa is very much in line with the advisedstrength of 10.8 MPa in NEN 8707 . Missing characteristics necessary for structuralassessment are used from bending class C22 (sawn timber) from EN 338 . A FEMmodel of section 4-1 of theMaaskade under different historical build ups has been set upin Plaxis 2D, and an Ultimate Limit State computation has been carried out on the finalbuild-up before replacement under four load cases. The found normative location thatcan be seen as the weakspot is the joint between the raking pile and the adjacent cappingbeam. A structural assessment based on sectional forces results in a negative outcome ofthe structure even on the self weight governed loadcase as unity checks > 3 are given for thecapping beam. These results do have the shortcomings due to simplifications from 3D to2D and a modelling with linear elements with no volume in the model and no allowancefor further load distribution beyond elasticity. A definite answer on the capacity in termsof additional external loads cannot be given and the need for a model that incorporatesthe exact lay out and positioning of the loads is stressed. Further recommendations forpractice are to find out if the capping beam- pile connections are expected to be able totake tension and to name their state after an inspection.

Glass is a commonly used material for façades and roofs. Recently even structural glass elements have been developed and the application of glass in structural elements is becoming more common. The ongoing development of new glass types and different production and processing methods resulted in the manufacturing of thin chemically strengthened aluminosilicate glass by AGC. Thin glass is mainly applied in the electronics industry, but the increased strength, optical properties, toughness, bending resistance and weather resistance make it a promising material for application in buildings. The Netherlands is the globe’s number two food exporter and more than half of the nation’s land area is used for agriculture and horticulture. Research on the optimisation of greenhouse designs is a hot topic in the Netherlands to maintain this leading position. The greenhouse industry provides an appropriate application for flat thin glass panels, because of the possibility to increase both light transmittance and structural performance. The goal of the research presented in this report is to determine the feasibility of the application of thin chemically strengthened aluminosilicate glass in greenhouse coverings. The research was divided into four topics that are relevant for greenhouse designs: building physics, structural properties, structural behaviour and economics. The building physics research was conducted in collaboration with the Greenhouse Technology team of the Wageningen University & Research. The light transmittance results showed an increased hemispherical light transmittance for thin glass when compared to regular float glass. The investigation of the structural properties of thin chemically strengthened aluminosilicate glass was based on available literature and the material properties provided by the producer. For this research a characteristic bending tensile strength of 260 MPa has been assumed. However, further research is recommended for the determination of the accurate bending tensile strength and design impact strength of thin glass. The structural behaviour of a thin glass panel in a greenhouse covering was investigated by executing both numerical and experimental analyses. The numerical analysis of the reference system showed that it is necessary to stiffen the thin glass panel for flat application in a Venlo greenhouse system. Multiple variants were designed and studied by numerical and experimental analyses. The IGU panel turned out to be the most promising variant for future application of thin chemically strengthened aluminosilicate glass in greenhouse coverings. As a main outcome it was concluded that thin chemically strengthened aluminosilicate glass has a better light transmittance, higher bending strength and increased impact strength than regular float glass. This leads to a higher crop yield and lower costs for transportation, construction, maintenance and insurance which makes thin glass an attractive alternative. At this moment, however, the material costs are very high and the decreased thickness and increased flexibility resulted in a lower stiffness. It is therefore not likely that a single layer of uncoated thin chemically strengthened aluminosilicate glass will result in a feasible greenhouse covering design. Nevertheless, the use of thin chemically strengthened aluminosilicate glass can result in an optimised greenhouse covering design when applied as an insulating (IGU) panel.

Amsterdam city is currently facing problems of old quay walls and bridges renovation, followed by insufficient greening in the city. This study aims to propose a method to increase Amsterdam's greenery that will add social and environmental value through the renovation work of quay walls. The main objective is investigating how the quay walls can be redesigned to gain improved moss colonization as the primary greening method. The research question is: “How can quay wall elements be designed with improved bio receptivity to stimulate high moss growth coverage that will add social and environmental values to Amsterdam citizens’ wellbeing?”. It is further divided into six sub-questions to gain knowledge of bio receptive definitions and concepts first, followed by the study of bio receptive construction materials properties in the second part. The third part aims to gain fundamental moss knowledge. Afterward, a moss field survey is conducted on construction materials in The Netherlands as the fourth part. The fifth part consists of the moss cultivation technique and experiment to gain more practical knowledge of the construction materials. Finally, with the acquired results, a bio receptive quay wall design with other practical considerations is proposed in the last part. Initiated with fundamental literature research on existing bio colonization works, followed by more specific building materials properties and moss knowledge studies on the first three parts. Afterward, a simple field survey on twelve sites has been conducted to determine moss growth conditions on building materials related to quay walls. Later on, an indoor moss cultivation method through the use of terrarium has been done to gain insights into material properties, ideal growing condition for mosses and moss cultivation technique. Based on the acquired knowledge, a simple quay walls element is redesigned to promote moss growth, keeping the site orientation in mind and moss cultivation practicalities. The first three parts' results will not be described since these are basic definitions and knowledge needed for the following three parts. During the field survey, the importance of moisture for moss growth on building materials is crucial. Therefore, not one specific material property value margin is needed, but a set of material properties and environmental conditions should be satisfied to gain successful moss growth. The duration of direct sunlight exposure will influence the site's moisture condition, which will further affect moss growth. Only twelve moss species were found and identified that are able to grow on construction materials, which is used for the moss cultivation method on the construction materials during the experiments. The use of a terrarium to test moss growth on construction materials followed by a moss cultivation idea gained interesting moss growth results. It turns out that the mosses' growing temperature should be below 25 degrees Celsius at all times, especially during the germination phase, followed by a humidity level above 80 percent. For this reason, significant moss growth results on the terrarium test samples are only gained during the end of the fall season and the winter season when the temperature is below 25 degrees Celsius. Sadly, this method is still uncommon, therefore, not fully understood and controllable; improvement on the temperature and lighting control of the terrarium test method is needed to further develop the terrarium test method into a moss receptivity testing method. Finally, the redesign of the quay wall element focus is to increase moisture gain through capillary action on the masonry finish of the quay walls. This can be achieved by using bricks with an Initial rate of absorption value above 3.0 kg/m2*minute and pointing made of either trass lime or lime 4 | P a g e mortar to promote capillary absorption of the masonry finish. Site consideration regarding quay wall orientation should be taken into account since this will influence the moisture condition and the moss cultivation technique time of application during winter and protection against external factor that prevents moss germination. It is concluded that moss growth on quay walls can be stimulated by particularly improving the moisture condition on the quay walls exterior finish, as moisture was found to be the key parameter that determines the presence or absence of mosses on concrete structures such as quay walls. Resulting in an increase in greenery in Amsterdam city, which can be further translated into social and environmental values such as better air quality by filtering airborne dust, stimulating the ecosystem by producing food for the primary consumer and followed by an increase in the benefits of access to nature to human health. How citizens will perceive the green moss quay walls is unknown, especially since the moss growth comes with other organisms' growth and is not evergreen throughout the whole year and how will the moss growth influence the durability of the material over a long period. Therefore, more studies and experiments regarding moss greening should be conducted to understand this greening method better.

Conventional construction techniques are unsustainable and expensive due to longer construction time, labour-intensive work, and the use of formwork. 3D concrete printing is seen as a potential substitute to overcome these issues. However, extrusion-based 3D printed structures exhibit a weak interlayer bond, and researchers have tried to address this problem through techniques such as using cement mortar layers or vertical steel reinforcement between the layers. This study aims to address the problem of the weak interlayer bond by implementing the phenomenon of 'topological interlocking' to increase the mechanical interlocking between the layers. The study performed scale model printing in the form of mould-casting and caulk-gun extrusion to produce specimens to analyze the effect of grooving on interlayer bond strength. The results were counterintuitive to the previously observed research, and the study recommends avoiding issues that may interfere in further similar studies.

The concept of sustainability takes into account a problem of urbanisation which causes a phenomenon of urban sprawl. In order to fight it, the strategy of urban densification is introduced and building upward extensions is one of the methods. However, investigating the feasibility of placing an extension on top requires a significant amount of time and effort from structural engineers. Therefore, this research aims to explore computational tools that would simplify the initial exploration process and make the option of extension more appealing. Theoretical background part of the thesis analyses conditions and limitations for building reuse, upward extension and use of timber. The main impediments that could prevent realisation of such project are found. The practical part of the research aims to explore parametric modelling and machine learning (ML) in order to produce a proof of concept ML tool which predicts how much an existing building can be extended based on its parameters. In order to have a sufficient amount of data, parametric modelling is used. For the first step, information is collected about seven realised upward extension projects in the Netherlands. This data defines the object for the parametric model which is built using Rhino plug-in Grasshopper. One part of the model analyses the existing structures with the goal to establish structural reserve while another part examines extensions. Six parameters defining existing buildings are chosen for iteration, by changing these parameters, a database of 8 652 fictional projects is generated. For the ML, the data is analysed and used for supervised learning where regression task is performed. Multiple linear regression (MLR) and nonlinear regression (NLR) algorithms are applied to make predictions which are validated using 5-fold cross validation (CV) and evaluated by calculating errors. Finally, the research presents a possibility and an example of using ML for extension exploration. The use of ML model during the initial stage of upward extension projects seems very appealing due to the quick feedback with limited information provided. A useful database of realised projects with a selection of structural parameters together with the incorporation of non-structural ones and a customised ML model should provide accurate predictions. However, the current problem of lack of data about realised extension projects needs to be solved.

Nowadays glass is more commonly applied as structural element, either as a replacement for, or in collaboration with conventional building materials such as steel, aluminium, timber and concrete. Key arguments to opt for glass in structural design are sustainability, aesthetics and transparency. As for all structural elements, glass elements are required to be structurally safe, even in extreme conditions such as during a fire. Building regulations demand a structural element to be able to withstand a fire for at least 30 minutes. There is however a lack of experimental results on the material properties and performance of structural glass elements at elevated temperatures. One of the key material properties that determines the performance of glass at elevated temperatures is its stiffness (Young’s modulus). In this research the Young’s modulus of both Sola Lime Silica (SLS) and Borosilicate (BS) glass is experimentally determined for temperatures up to 700°C. The transmittance time of high-frequency sound waves (ultrasound) is measured for both BS as SLS glass rods during heating in a tube furnace. From this data the Young’s modulus has been derived mathematically. Additionally, the effect of a low-E coating and an intumescent coating on the performance of laminated glass panels is experimentally determined and assessed. During heating of only one side of the laminated glass panels, the time until the interlayer starts to form gas bubbles is recorded, whereas the temperature of the glass has been measured on both sides of the glass panels. From the experiments it is observed that glass performs well up to temperatures of 500 °C, provided there are no distributed thermal stresses present in the glass. Given this condition, the remaining stiffness at a temperature of 500 °C is 90% for SLS glass and 102% for BS glass. As for structural steel this is only 60%, it is concluded that both SLS and BS glass outperform steel in terms of relative stiffness at elevated temperatures. Between 500 and 600 °C a sudden deformation is observed. Therefore the structural safety of a glass element cannot be guaranteed for temperatures beyond 500 °C. The heating of a glass element can be delayed by the application of an intumescent coating. For low-E coating, an improvement in fire resistance is however not proven in this research. Instead, a negative effect has been observed and therefore the application of low-E coating is not recommended. It was shown that the PVB interlayer is the weakest point of the glass element. At temperatures of 200 °C the PVB interlayer is already completely molten, while at 500 °C the glass is still intact. The fire resistance can be improved by applying glass without an interlayer.

To meet the climate goals set by the government, the building sector needs to reduce its contribution to the environmental burden on society. However, the current situation in the Netherlands presents a major challenge to build more to reduce the housing shortage, while at the same time reducing its environmental footprint. Therefore, alternative solutions to the status quo should be considered, which can reduce the environmental impact of buildings. The goal of this thesis is to determine the environmental impact of multi-storey timber residential buildings and to make a comparison with a concrete building. Furthermore, the effect of cascading strategies on the environmental impact is analysed and the carbon sequestration potential by timber residential buildings estimated. Firstly, reference projects are studied to determine the trends in the timber construction sector. Based on these results, the main timber typologies and available design choices are mapped as well as the available (engineered) timber products available on the market. Secondly, the sustainability of timber structures is assessed by performing a literature study on three different scales: the macro-, meso- and micro-scale. The macro-scale represents the global forestry level in which the carbon cycle, carbon sequestration (i.e. capture and storage) and forest certification are discussed; the meso-scale represents the building level in which the durability and cascading strategies (i.e. strategies to elongate the lifespan) are discussed; the micro-scale represent the environmental impact of the material itself. Thirdly, the environmental impact is quantified using the fast-track life cycle assessment methodology. Two data sources are evaluated by performing a data analysis. The first being the ‘Nationale Milieu Database’ which is prescribed by the Dutch ‘Milieuprestatie Gebouw’, the second being Environmental Product Declarations according to the European EN15804 standard. For the two main timber typologies (mass timber and post&beam) a variant study is set-up using a parametric environment. The variant study analyses the environmental impact of main load bearing structures, the relative contribution of structural components and the effect of cascading strategies. The research is concluded by a case study in which the environmental impact of a timber alternative is compared with an equivalent concrete benchmark. Based on these results the global warming reduction potential of timber residential buildings is determined. From this research, it was shown that the environmental impact of timber buildings is lower than a concrete equivalent. However, it was found that the production capacity of engineered timber proved to be currently insufficient to reach the market potential, resulting in upscaling challenges for the engineered timber manufacturers when the demand will increase. From the data analysis, it was found that the selection of timber environmental data sources is highly sensitive. Furthermore, it was found that the choice for structural typology does not lead to significant differences for a default design lifespan. Though, the choice for a certain floor system does result in large differences. Overall, it can be concluded that a difference can be made to the environmental impact of the built environment by cascading scenarios, regardless of the choice of construction material. In case of timber structures, additional benefits occur due to the lower relative environmental impact and carbon sequestration.