Given the importance of modularity in structural design, understanding the performance of modular shell structures is essential for improving both circularity and construction efficiency in spatial structures. To enhance sustainability and aesthetics, timber gridshells can be used to integrate sustainable building materials with complex pattern topologies. Modularity not only contributes to circularity of building materials, but also eases assembly, reducing both cost and construction time. By investigating different segmentation strategies, their impact on structural behaviour and buildability can be identified. This knowledge supports the optimisation of modular gridshells, leading to more efficient construction solutions.

This research aims to explore optimal segmentation strategies for timber gridshells, considering structural behaviour, element reusability and the efficiency of production, assembly and transport. A timber geodesic gridshell dome serves as a case study, but the findings contribute to modularity of gridshells in general. The main research question is: How can the modular segmentation of timber gridshells be designed to optimise their structural and construction efficiency?

For this research a method is developed to generate modular gridshells and optimise their design by evaluating both structural performance and construction efficiency. The modular designs consist of pinned splice joints that longitudinally connect two beams of different modules. Various modular designs are created by defining the location of these intermodular joints, thereby determining the overall modular geometry in the structure. A structural analysis gives understanding of the structural behaviour and the required material use. A construction analysis provides insight into reusability and efficiency of production, assembly and transport. A multi-objective comparative analysis is conducted to identify the most favourable designs based on project goals and stakeholder preferences.

Findings show that this modular approach improves assembly efficiency and the reusability of elements. It is particularly advantageous to choose a modular gridshell over a classic one when the primary design objective is reusability. However, the modular segmentation method negatively affects structural performance and increases material usage, primarily due to the use of pinned splice joints, which reduce overall stability. Additionally, applying modularity results in lower production and transport efficiency.

The results further indicate that larger modules improve structural stability and reduce the required material, due to fewer splice joints. Larger modules also result in higher assembly efficiency and reusability. However, increasing module sizes may exceed maximum transport size limits. It could also lead to a higher number of module types, reducing production and assembly efficiency. Furthermore, the module shape significantly influences the number of splice joints, underlining the importance of careful geometric consideration to minimise joint quantity. Additionally, increasing the rotational stiffness of splice joints could improve the structural performance.

In conclusion, it is crucial to consider project objectives and stakeholder interests in the structural design of a gridshell. Moreover, this research concludes that modular gridshell designs perform best when:
• Module sizes are maximised within transport constraints;
• Module shapes are designed to minimise the number of splice joints;
• An increase in module size comes with a minimisation of number of module types.

The construction industry faces an urgent need to reduce its environmental footprint, in which the adoption of bio-based materials is a valuable step. However, the use of such materials in façades remains limited. This thesis, conducted within the MSc Civil Engineering (Building Engineering track) program at Delft University of Technology, in collaboration with ABT Consulting Engineers, uncovers the experienced challenges and addresses them by developing an information product for start-ups aspiring to bring bio-based non-structural closed façade products to market.
The research focuses on the knowledge and performance aspects necessary for start-ups lacking access to expert consultancy. Through a combination of literature research and interviews with start-ups and industry stakeholders, the study identifies key barriers: difficulties in product testing, difficulties navigating certification and regulatory frameworks, lack of standards tailored to bio-based materials, unfamiliarity with the use of bio-based materials, and difficulty with guarantees on supply, quality and production. Literature was reviewed on bio-based materials (e.g., flax, hemp, straw, cork, mycelium), façade design principles, façade performance (structural, fire, water, air, thermal, moisture, and acoustic), testing methods, and the legislative framework surrounding building products in the Netherlands.
The research methodology involved three phases: (1) expert dialogues to capture industry insights, (2) product development, using the state-of-the-art and results from the expert dialogues, and (3) validation through a feedback questionnaire with the target audience. The expert dialogues, taking place with start-ups, bio-based experts, and building (physics) experts, revealed advice from experience: certification should not be the main focus, but a means to help sell products, and adopt a go-to-market strategy that starts in an accessible market. The experts also gave insight in the useful knowledge from the state of the art, such as information on design tools such as UBAKUS or simple Excel models, testing methods such as compressive and flexural strength, bonding, UV, freeze, and fire resistance checks, how to comply with relevant standards by testing, and sustainability measurement tools such as LCA, MPG, BCI.
The final product is an interactive information guide designed specifically for start-ups. It navigates users through early-stage product development phases, including material selection, performance requirements, indicative testing strategies, and certification (including CE marking). The guide's format follows practices for user engagement: visual, intuitive navigation, and different layers of depth.
In conclusion, the thesis successfully creates a practical, targeted resource that empowers bio-based product start-ups to bridge critical knowledge gaps, increase their market readiness, and contribute to the sustainable transition of the built environment. The findings stress the importance of flexible certification frameworks, simplified early-stage testing, and stakeholder involvement to enable broader acceptance of bio-based innovations in construction.

The issue of climate change has become highly important over the last decades. All sectors need to find solutions in order to reduce the carbon footprint and the built environment sector is definitely not an exception to this. One of the solutions is to use more biobased materials, such as timber. The use in timber is not only limited to low-rise buildings, more mid- and high-rise buildings are being built as well. The number of buildings including timber with at least six stories was increased from 32 in 2015 to 115 in 2023.

Even though the number of timber buildings is increasing, the actual environmental impact is largely unknown. This is because there is no commonly-used method to calculate the carbon footprint of a building which is complete and correct. Currently, the MPG (MilieuPrestatie Gebouwen) and the method described in the Paris Proof Agreement are mainly used in the Netherlands. The MPG uses the Environmental Product Declarations (EPDs) from the database from the NMD viewer, but this viewer does not provide the essential information for the user to choose the proper EPD. The Paris Proof Agreement disregards the end-of-life phases, which leads to incomplete results. Therefore, another method was developed to calculate the carbon footprint and to determine the difference in carbon footprint between a concrete and/or steel structure with a timber-hybrid structure. This method uses two sets of phases: phases A-C and phases A1-A5. The former uses all relevant LCA phases and will provide the most accurate results, while the latter can be used to compare the results to the Paris Proof Agreement limits. Phases A4 and C2 (transport to and from the building site) and modified to fit the current projects.

Two case studies were used for this research. The first case study is KasseNova aan de Vaart, a seven-story residential building made of concrete. The carbon footprint is calculated for this concrete design, as well as three design variants including CLT floors, CLT walls and a combination of the two. The second case study is Apollolaan 171, a six-storey office building made of steel and concrete. The design variants include glulam columns, CLT floors and beams and a combination. For all variants, design calculations of the timber elements were performed. For CLT elements, two end-of-life scenarios were considered: 100% recycling and 100% incineration. The current design of KasseNova aan de Vaart has a carbon footprint of 3,145 ton CO2-eq. when phases A-C are considered. In the scenario that the floors and walls are replaced by CLT, the carbon footprint is decreased by 63.1% when the CLT is recycled, while this is decrease is 12.7% when the CLT is incinerated. When phases A1-A5 are considered, the current design has a carbon footprint of 222.46 kg CO2-eq./m² (above the 2021 Paris Proof limit of 220 kg/m2) and the CLT floor and wall design variant has a carbon footprint of 35.12 kg CO2-eq./m² (below the 2050 limit of 50 kg/m2), including biogenic carbon uptake. The current design of Apollolaan 171 has a carbon footprint of 1,671 ton CO2-eq. (phases A-C). For the scenario in which the floors, beams and columns are replaced by CLT and glulam, the carbon footprint is reduced by 89.2% (CLT recycled) and 49.8% (CLT incinerated). Considering phases A1-A5, the carbon footprint of the current structure is 255.17 kg CO2-eq./m2 (above the 2021 limit of 250 kg/m²), while the carbon footprint of the structure including CLT and glulam elements is -44.93 kg CO2-eq./m² (below the 2050 of 50 kg/m²).

These results show that an increase in timber in the structure leads to a reduction in carbon footprint. This is because timber takes up carbon in the product stage. However, the amount of reduction depends on several factors. If the CLT is recycled at the end of its lifetime, the reduction will be more significant than if the CLT is incinerated. When the structure includes concrete, the carbon footprint depends on the type of cement being used in the concrete. CEM I will lead to a higher carbon footprint than CEM III. For structures including steel, a higher percentage of recycled steel leads to a lower carbon footprint. Also, in general, the country of production influences the carbon footprint. If a country has a high percentage of coal in its energy mix, the carbon footprint will be higher.

The built environment faces the challenge of meeting the sustainable development goals of the Paris Agreement with regards to building emissions. One aspect of this challenge is the energy transition from fossil to more sustainable sources. A possible solution lies in the field of solar energy technology which, over the last decades, has become the main sustainable energy source globally. Various types of solar cells exist today, from large-scale solar parks to small strips of flexible organic photovoltaics, or OPV. In parallel, the field of tensile architecture provides answers to the materiality challenge of the same sustainable development goals. Tensile architecture is lightweight by nature, which reduces the material use. This reduction in turn limits the embodied carbon of the material.

The current body of knowledge regarding textile engineering shows a wide variety of different types of textiles in architecture. In parallel, the knowledge around the bending of semi-rigid elements such as the OPV strips supports their use in curved geometries. However, gaps remain relating to the use of uncoated textiles in tensile structures, as well as the non-adhesive integration of semi-rigid elements such as OPV strips.

Given the context, the main research question of this thesis was:
To what extent can an uncoated woven hybrid textile, using non-adhesively integrated solar cells, be applied in doubly curved tensile structures?

SUNTEX, a newly developed hybrid textile consisting of rPET yarns and slender OPV strips, defined the scope of this research. A number of design parameters was established to determine the largest possible surface area, or maximum coverage, of OPV strips on a hyperbolic parabola and a saddle surface between arches, or barrel vault. To this end, a two-step computational analysis, using the Easy and Rhino Grasshopper software packages was performed. The analysis tool was designed to be compatible with current, conventional design workflows.

Results from the research showed an OPV strip coverage on the hyperbolic parabola of 23%. This best case scenario was produced on a shape which was divided into 5 cutting pattern segments. The barrel vault supported a maximum of 30% of the total surface area. This coverage was achieved on a shape which was divided into 5 cutting pattern segments. These results are global optima, as either increasing or decreasing the numerical design parameters results in a reduction of coverage on both shapes.

The conclusion of this thesis is that SUNTEX can be applied on doubly curved surfaces with a coverage up to 30%, depending on the type of shape that is used in the design, as well as the right combination of design parameters. Within a design sequence, the iterative analysis method that was researched in this thesis should therefore be applied twice. Once at the early design stages, and once at the detailed design stage.
It is recommended that the design parameters are further explored to better understand their influence on the coverage on various shapes. Apart from that, the analysis method itself should be evaluated to reduce the run time, and improve of the accuracy of the results.

Foundations of buildings ensure the safety and serviceability are upheld. A common type of
foundations used in the Netherlands is pile foundations which are typically founded on a thick sand layer in the subsurface. These pile foundations are the focus of this thesis and more specifically the methods used to design such foundations. This thesis aims to give a better understanding of the resistance of closed-ended piles in a layered soil by comparing existing pile design methods to the measured forces from the Drukpaal jacking machine. Drukpaal jacks precast concrete piles into the soil and the records collected give a valuable insight in the pile resistance in various locations and soil profiles with layered soil in the Netherlands.

The design of a pile foundations consists of the combination of two different types of methods. One will predict the base capacity of the pile foundations and the other will predict the shaft capacity. These two capacities together give the predicted bearing capacity of the pile. However, multiple base capacity and shaft capacity methods exist with varying influence zones and with that varying degrees of accuracy. In this thesis the different base and shaft capacity methods used are all based on the tip resistance as measured by a CPT. The following base capacity methods are included: Koppejan, LCPC, Filter method and the Filter method as adapted by Munta de Boorder (in this thesis referred to as the Munta de Boorder method). And for shaft capacity the NEN method and the ISO method are used.

This thesis aims to answer the following research question: What combination of capacity prediction methods for shaft and tip resistance works best to estimate the total force over depth as measured by Drukpaal?.
This question will be answered by a series of simulations of different projects completed by Drukpaal, which is a company which jacks piles into the ground and records the required force over depth.

The measurements and simulations for the various sites were compared both visually and
statistically. The Filter method with ISO gives the best visual fit.
For the statistical analysis the coefficient of variance (COV) is taken as well as the root mean squared error (RMSE) of the ratio line of the simulation (simulation divided by the measurement). Here the COV will account for the shape and the RMSE will account for the overall error. The sum of these two values is used to determine the best fit, since both of these values should be as small as possible. From this analysis it is found that Filter method in combination with ISO is overall the best combination, followed by Munta de Boorder with ISO and Filter method together with NEN.

The last aspect to be looked at is the location dependency of the combination of methods. From this it was found that the base capacity methods in combination with NEN vary a lot over the measured locations and these combinations are thus location dependent. For the base capacity, the LCPC method was also found to be location dependent in combination with ISO. So even though this combination worked really well for one of the projects (Gorinchem) it is not dependable to use because of the varying degrees of accuracy. The other three combinations; Koppejan, Filter method and Munta de Boorder together with ISO, were all found to be location independent. However, Koppejan with ISO garnered quite high values for RMSE and COV, meaning that this combination is not very accurate.

Overall, Filter method with ISO was found to give the best fit which was location independent. Munta de Boorder with ISO followed and Koppejan with ISO was found third best fit. The other combinations were found to be location dependent and thus are, based on the work in this thesis, less suitable for application in The Netherlands.

The main focus of this thesis is on a thin glass sandwich panel combined with a three-dimensional printed core pattern. The core pattern provides stiffness to the panel, but it also influences the daylight transmission. The goal of this research is to design a façade system which can dynamically improve the daylight performance, effectively control the illuminance inside the building together with preventing disturbing glare.

The research first evaluates the theory behind thin glass, the structural sandwich structure and how the design of a façade panel correlates with its visual comfort. The properties of existing dynamic systems are evaluated, together with exploring other possible dynamic systems that can be integrated in the panel.

The resulting system, a hexagonal core pattern with integrated inflatables, is evaluated on its structural performance and daylight performance using analyses executed in the grasshopper model. This is further expanded by studying the structural performance of more complex core geometry using Diana Finite Element analyses. From the results of these evaluations, a design strategy is created which is able to find the optimal properties of the inflatable façade system.

This design strategy is then applied to a case study, to show both the design of a single façade panel, as well as the full façade system of the whole building. The final result is the design strategy for the dynamic inflatable façade system.

The presented research aims to design and optimize a timber observation tower, with a primary focus being the influence of topological and curvature parameters on its stability and lateral stiffness in resistance to non-uniform wind load profiles.

Having recognised the environmental benefits and urgency to find other alternatives, there's a clear necessity to incorporate wood as the main construction material into the infrastructure projects, like observational towers. By conducting a study on hyperboloid towers implemented in the last 100 years, this project questions the necessity of in plane stiff platforms, flexurally stiff rings and continuous vertical members as being pivotal to the stability and lateral stiffness of the global structure when subjected to non-uniform wind loads. In addition, the study intends to investigate how the narrowness of the hyperboloid might affect the lateral stiffness of the structure. Thus, by utilizing parametric tools (Grasshopper, Karamba3D and Beaver plug-in), the study aims to design a timber tower structure comprised of fully segmented members as well as incorporation of circular (flexurally stiff) rings, aiming to address the questions raised. In terms of structural member arrangement, the study will investigate two topologies: one featuring a diagrid pattern that emulates a geometrical shape of an antiprism, and a custom pattern inspired by the post and beam approach, which resembles a regular prism shape. The study emphasizes the tower's multi-functionality and adaptability throughout its lifespan. Tower's main structural framework is a pivotal element in providing required stiffness and strength by excluding the need for in-plane reinforcement provided by arbitrarily placed platforms.

The key realisation of this research was the kinematic behaviour exhibited by the segmented, triangular tower, adversely impacting its stability characteristics. The study used a combination of analytical and graphic kinematics techniques, along with a physical mock-up model, to confirm the kinematic behavior of the tower given that even sided polygons for rings are incorporated. This revelation would have an impact on how a structure like that would perform as well the way it would be built. Further research unveils the strong influence of ring type on structural stiffness showing that segmented rings render tower structures less stiff than ones employing curved ring members, regardless of the pattern. In terms of the direct comparison between tower patterns, custom one demonstrated a more consistent and stable performance in general, particularly achieving higher stiffness levels when employing segmented rings. As regards the triangular pattern, the stiffest response against wind loads has been exhibited through the use of curved rings. In addition, the study validates that adopting a hyperboloid shape along with smaller shape factors for the global tower geometry yields more favorable lateral stiffness characteristics. Finally, the study navigates through the exploration of the most optimal connection design, illustrating how considerations related to detailing have necessitated a re-evaluation of the most optimal tower configuration, which initially was chosen to be a triangular one equipped with curved rings. A qualitative assessment of a potential joint within this specific tower variant has confirmed that designing such a connection is significantly more complex. This is due to the necessity of ensuring the continuous flow of the curved ring, emergence of a kink within the insertion of the plate and how that is needed to be addressed.

Alternatively, these considerations have motivated the design process to converge into a new hybrid design, integrating segmented rings with a curved top ring defined by the custom pattern. This choice has been made by conducting a separate parametric study of the new tower design and ensuring that the new connection design fulfills elastic slipping modulus and ultimate strength requirements. The final topology that showed higher stiffness metrics was the custom one. It's also highlighted that maintaining the top of the tower constrained leads to favorable effects on stability and stiffness, irrespective of the chosen topology. The resulting structure is optimized for mass by strategically reducing member cross-sections in accordance with connection scheming while adhering to both SLS and ULS criteria.

The urban heat island effect is a well-known and pressing problem in cities today related to urbanisation. It is the phenomenon of an increased ambient air temperature in cities compared to the surrounding rural areas. The use of nature-based solutions has been proposed as a way to help solve this problem. These interventions use nature and biodiversity to improve urban sustainability. By replacing materials that accumulate a lot of heat, the urban heat island effect is tackled. One way of doing this is by making use of so-called bioreceptive concrete on our facades, which allows for the biological growth of mosses to take place on the concrete substrate itself, without requiring any additional systems or maintenance.
This master thesis aimed to quantify the evaporative cooling effect of these moss-covered concrete facades on the urban environment. The research objective was to measure and model the amount of cooling resulting from the evapotranspiration of moss, by analysing water uptake and release, as well as the temperature decrease of a façade surface as a result of evaporation.
Laboratory experiments were conducted to examine the evaporation rates of various moss species under controlled ambient conditions. Bryum capillare displayed the highest water uptake, water retention, and drying time, with the ability to take up 32.4 g of water per 83 x 83 mm surface area. This is equivalent to 4703 g of water per square meter or 470 kg/m3 volumetric weight. Pleurocarpous mosses showed a range of 27 to 27.4 g of water uptake, corresponding to 3919 to 3977 g of water per square meter or 392 to 398 kg/m3. The concrete itself absorbed 21.1 g of water, which is equal to 3063 g of water per square meter or 204 kg/m3 for the 15 mm thick sample that was tested.
Evaporation rates were found to be higher immediately after a watering event, with variability observed between different moss species. Highest variability was 5.56 g/h for Eurhynchium striatum versus 1.86 g/h for Syntrichia ruralis. However, after a certain time, most mosses exhibited similar evaporation rates. The exception was Bryum capillare, which consistently maintained a higher evaporation rate. This moss, growing in cushion form, demonstrated enhanced drought avoidance due to a reduced surface-to-volume ratio and additional capillary spaces for water retention. The highest levels of evaporation were observed in all moss species under conditions of high temperature (25°C) and low relative humidity (50% RH).
Field testing involved monitoring the temperature of two bioreceptive concrete façade panels, one covered in moss and the other left bare. On sunny days, when panel temperatures exceeded 15 to 20 °C, and the panels were dry, the moss panel temperature was 0 to 5 °C lower compared to the bare concrete panel. This temperature difference was attributed to the lower albedo of the moss (0.07 – 0.11) compared to the concrete (0.10 – 0.40). The moss absorbs more solar radiation and prevents it from reaching the surface beneath it. Infrared camera measurements confirmed that the dry moss surface temperature was about 2 to 3 °C warmer than the concrete panel surface due to lower albedo of the moss. On rainy or cloudy days minimal temperature differences were observed between the panels. Additionally, the moss acts as an insulation layer, trapping the air between its leaves, keeping the material behind it cooler. The potential implications of this additional insulation layer on top of the facade remain to be investigated. Based on its specific heat capacity and heat conductivity, it could help with heat gain in winter and cooling gain in summer. It is hypothesised that moss has a lower thermal mass than concrete, potentially facilitating quicker heat dissipation at night and contributing to reduced building surface temperatures.
Watering the panels significantly reduced surface temperatures, with the moss panel being 2 to 5 °C cooler than the concrete panel when wet. The moss exhibited higher water absorption and longer water retention compared to the porous concrete, enabling more evaporation resulting in lower façade temperatures. This cooling effect persisted for approximately two and a half hours after a 40 ml watering event, equivalent to a 1 mm rain event at low wind speeds. These findings indicate that applying moss on a concrete facade cools the surface temperature of a façade compared to a bare concrete façade.
A non-stationary model based on the energy balance of the facade system was calibrated using field testing data. This model provides accurate temperature profiles under different weather conditions. Evaporation modelling was calibrated using water events but could be improved by implementing a water balance. By computing the irrigation, precipitation, evaporation, throughflow and runoff in a dynamic balance, the evaporation and temperature profiles would become more accurate.
The model is used to simulate a heat wave and the thermal behaviour of the façade after rain events with different intensities. A 1 mm rain event decreases the surface temperature of the façade with a few degrees but the effect does not last for a very long time. A 10 mm rain event decreases concrete surface temperature up to 10 °C initially, and the effect lasts for a few hours. The length and intensity of cooling can be extended through the application of moss on a façade. Then, for a 10 mm rain event, the initial temperature reduction is equal to 15 °C. To increase this effect, the pore volume of the concrete could be increased. Also, a moss species should be cultivated on the concrete which grows in cushion form, is desiccation tolerant, and has natural protection against UV light.
The thesis concludes that applying bioreceptive concrete on facades has the potential to mitigate the urban heat island effect by maintaining cooler temperatures for an extended time following rain events depending on their severity. This approach replaces materials that accumulate and radiate excessive heat. To quantify the effect of bioreceptive concrete as a mitigation strategy more accurately, a computational fluid dynamics (CFD) model could be made to predict the ambient temperature decrease of the air in front of a bioreceptive facade.
By investigating and quantifying the evaporative cooling effect of moss-covered concrete facades, this thesis contributes to the understanding of nature-based solutions. The findings highlight the potential benefits of incorporating bioreceptive concrete in building facades to mitigate the urban heat island effect and improve thermal comfort in urban areas.

The present Master thesis explores the implementation of a glare-based control strategy for Venetian blinds in buildings with totally transparent facades. The case study concerns the Co-Creation Center, a building that hosts three different types of events: presentations, meetings and workshops. The diverse occupancy patterns, coupled with the four fully glazed facades, make the effective blinds control a challenging task to achieve using a traditional rule-based approach. Therefore, in this project, an optimized control system is proposed, aiming at the minimization of visual discomfort due to glare, as well as the minimization of energy demands for electric lighting by increasing daylight entry. The control strategy is developed within Grasshopper, a promising tool for parametric and optimization problems. Grasshopper allows for the creation of a parametric model that can be adjusted to other similar buildings with fully glazed facades by modifying the input parameters. Radial Basis Function Optimization (RBFOpt), a model-based optimization method performed by Grasshopper’s component Opossum, is utilized for the computation of the optimal blinds’ states. within the developed control strategy, Ecyl is used as a glare index, giving the opportunity to evaluate its performance. Results show that the developed algorithm can improve the existing visual conditions in the Co-Creation Center by an average of 80% for all activity types, although it led to an average increase of 7% in the time steps where electric lighting is needed, in comparison to the current control. Nevertheless, the time-consuming ray-tracing process performed by Grasshopper for each time step and the non-automated use of the RBFOpt component Opossum, slowed down the optimizations and made their use rather unsuitable for real-life implementation of the control strategy. Despite the impractical use of Opossum, RBFOpt was proved a promising optimization method. Finally, Ecyl displayed an overall agreement of 92.5% with DGP, proving that in spaces with multiple windows and uncertain occupants’ view direction, a view-independent index can predict glare risks adequately well, after being carefully correlated with another reliable view-dependent metric.

This research aimed to design a modern-day quay wall that can host ecologically valuable species by using pervious concrete, which offers a suitable growing layer for plants due to its high interconnected porosity. The study investigated which vascular plant species are dependent on quay wall ecosystems in the Netherlands and determined the ecological requirements that contribute to their growth. The experimental research optimized the water retention of pervious concrete by using two types of coarse aggregates and different water-to-cement ratios. The results showed that pervious concrete can be optimized by adjusting the aggregate type for a water-to-cement ratio between 0.4 and 0.6, and that the use of pumice stone enhanced the water absorption of pervious concrete by a factor of approximately 2.5. Additional testing is needed to determine if a mix design with pumice stone aggregate can fulfil the technical requirements. An inflow-outflow model is utilized to predict if the current design variant, consisting of substrate layer made of pervious concrete and soil in combination with a reservoir in the capping stone, can provide sufficient moisture to the vegetation. The findings indicate that the proposed quay wall can host ecologically valued species to a certain extent, but optimizing the design by investigating the potential of pumice stone as coarse aggregate is recommended. Furthermore, the capillary effect in the substrate layer should be investigated as sufficient rise is needed to prevent the need for a minimum form of maintenance.

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.

This thesis project proposes the introduction of bio-based materials in the design of unitised curtain wall façade systems. The work investigates a circular bio-based unitised façade design to understand its feasibility regarding thermal, technical, and environmental performance. The research is divided in four phases, including the material, system design, performance, and environmental assessment level.
The material phase serves as a literature review to study the current technologies and available bioproducts in the market to make an informed selection. Once the materials are selected, the system design phase starts with an emphasis on dynamic construction and design for disassembly features.
Overall, this study aims to minimize reliance on non-renewable resources such as aluminium in façade systems. Therefore, it is important to analyse the thermal and hygrothermal behaviour of the materials to integrate design characteristics that can improve their performance while protecting their structural integrity.
After the feasibility of the design concepts gets validated, a comparative environmental assessment against standard aluminium façade systems is conducted to quantify the sustainability impact of the proposed system. Ultimately, the research project proposes a detailed exploration into the feasibility of circular, bio- based unitised façade systems. Therefore, the introduction of bio-based systems that support sustainable methodologies and practices from the material, design, and system level is demonstrated.

This thesis investigates the potential for natural ventilative cooling strategies to improve the cooling and comfort of residential midrise buildings in the Netherlands. Ventilative Cooling is “the application of the cooling capacity of the outdoor air flow by ventilation to reduce or even eliminate the cooling loads and/or the energy use by mechanical cooling in buildings, while guaranteeing a comfortable thermal environment”. The effect of Day and Night ventilation strategies on the indoor environment of two common typologies of midrise apartments seen in the Netherlands was evaluated. The project investigated window and stack ventilation using dynamic energy simulations coupled with airflow network (AFN) modelling. EnergyPlus airflow network model was used for simulations with Grasshopper and Rhino as the user interface. Honeybee and Ladybug plug-in for Grasshopper translated the model into the EnergyPlus-readable input format. Various performance indicators were used to evaluate the apartments' comfort and cooling. These included temperature limit exceedance hours, GTO hours, Cooling requirements reduction ratio, Climate Potential for Natural Ventilation (CPNV), Natural Ventilative Cooling Effectiveness (NVCE) and Climate Potential Utilization Ratio (CPUR). Ventilative cooling simulations yielded favorable results. There was a significant reduction in the peak temperatures and GTO hours within the rooms when the windows were opened, compared to when they were closed. Out of the tested two typologies of apartments, the number of hours when the temperature exceeds 28°C reduced by 50-70% when the windows were fully opened in typology 1 apartments and was reduced by 36-70% in typology 2. GTO hours reduced by 70-80% when the windows were opened for ventilative cooling in typology 1 apartments and reduced by 55-60% for typology 2 apartments in comparison to when they were closed. Apartments with the capability of cross ventilation performed better than those with only single-sided ventilation. The cooling effectiveness of the existing building designs was also evaluated. The results showed that there is room for improvement of design to utilize the site’s potential for natural ventilation. When passive stack is used along with the opening of windows in an apartment, there was a slight reduction in temperature when compared to using only open windows for the same apartment. However, the reduction was not very significant. The findings are presented in a comparative and quantitative manner, providing valuable insight into the relevant field.

Seismic events have shown the hazardous and expensive consequences resulting from seismic damage of non-structural elements. For this reason, the concern regarding the seismic performance of glazed curtain walls has acquired more relevance in the building industry; however, there is still a gap of information in the literature about this topic. To contribute with a broader panorama about the seismic performance of CW, this thesis project is focused on the seismic of the connections within a curtain wall.
This thesis intends to evaluate the performance of the connections that contribute to the seismic response of a glazed curtain wall with finite element models and experimental tests. To achieve this objective, several important points were taken into account. First, a literature study to understand what is a CW, and which are the components that may have influence in seismic design. Second, the two case-studies considered in this research are presented; in this section information about the specimens tested and types of tests performed is provided. Third, elaborate finite element models of the connections corresponding to each case study describing the criteria used. Finally, a comparison between the experimental and numerical results is elaborated to determine if the modelling approach is correct.
The experimental tests were carried out with the collaboration of Permasteelisa Group, and the numerical models were elaborated with DIANA FEA software. Five connections were analysed in this research: mullion to mullion, transom to starter sill, top aluminium bracket and hook, starter sill- bottom steel bracket, and silicone by a non-linear analysis with incremental displacements. At the end of this analysis it was observed a good agreement in the behaviour of the frame to frame connections with a minimal over estimation of the stiffness of certain frame to frame connections. Regarding the connections involving brackets, it was observed that the behaviour in the in-plane horizontal direction can be affected by the rotation of this elements because bolted connections shall be modelled as rotational springs. Finally about silicone it was observed that there exists a good match between the experimental results and the numerical models.
In conclusion, the modelling procedure was validated with experimental tests with relatively optimal results. Nonetheless, there are still limitations in the development of this topic that will be described in the recommendations but much more openness is expected in the future in terms of research on this topic.

Especially in colder climates, like The Netherlands, a large quantity of non-renewable energy is used for space heating by burning natural gas. To meet climate goals, natural gas should be replaced with renewable sources. Reducing the total energy demand for space heating and lowering the design water temperature in a heating system enable more renewable energy production alternatives for space heating. So high temperature heating (HTH) systems need to be replaced with low temperature (LTH) alternatives to get dwellings through the energy transition.

Despite the indisputable advantages of LTH, it also comes with risks. One risk is that heating elements need to become exceedingly large to ensure sufficient heating capacities. Insufficient capacities may adversely affect indoor thermal comfort. To mitigate this effect, extra measures should be taken in the façade, ground floor and roof to reduce infiltration and increase insulation. In order to introduce these measures a renovation should be carried out. This study will focus on façade renovations.

For the assessment of comfort levels when changing to LTH, this research presents a case study into a typical Dutch terraced dwelling. This case study was carried out through simulations in TRNSYS 17. This is a validated program simulating energy flows in transient systems. Although TRNSYS 17 has built-in comfort calculation options, these were not deemed sufficiently transparent in their workings for this study. Furthermore, calculations of view-factors, mean radiant temperatures (MRT) and the predicted mean vote (PMV) showed deviations from standards NEN-EN ISO 7726 and 7730. Therefore a workaround is presented which calculates comfort levels closer in line with standards.

Two façade options were investigated for 1 HTH and 3 LTH systems. The HTH model was calibrated to match measured air and surface temperatures of a test dwelling. LTH was then simulated while keeping the current radiators, which showed that diminished capacities significantly reduce comfort and façade renovations cannot realistically mitigate this. This option is not possible when changing to LTH in dwellings in general. Then a system with specialized LTH radiators was investigated, with capacities determined through ISSO 51. This still showed a high peak of discomfort at current insulation levels. Comfort levels were improved significantly after a renovation to match the new ‘Target Values’ (‘Streefwaarden’) for insulation and an ‘excellent’ qualification for infiltration reduction. Finally, underfloor heating was investigated, resulting in enhanced comfort levels both with current and updated insulations levels. In all cases, a renovation has a positive effect on comfort levels and reduces heat transfers.

This research investigates how to design a glass pedestrian bridge that is structurally optimised for multiple load scenario’s and feasible in terms of fabrication and construction. Linear glass elements such as panes have limited freedom of shape. On the other hand, cast glass can be produced into any shape possible. When glass is used in large quantities with large cross-sections, the annealing process can take a long time and require a significant amount of energy. The annealing time must be kept to a minimum to make cast glass a viable option. This is where topology optimisation can play its part. During topology optimisation, the layout of an element is optimised on the given constraints for the specified design domain. A compliance-based optimisation is found to be the most suitable objective function. The software package Ansys and various plugins for McNeel Rhinoceros/Grasshopper are compared on their topology optimisation tool. During this comparison, Ansys is found to be the most suitable software. This is mainly because of the possibility of implementing a cross-sectional constraint during the optimisation, which is needed for implementing a maximum annealing time. The most suitable production method for topology optimised cast glass elements is found to be kiln casting with a 3D printed sand mould. Glass is a brittle material with a low tensile strength compared to its compressive strength. The only type of bridge that can be made entirely in compression, without pre-tensioning, is an arch bridge. This bridge type is used for the final design. The loads considered during structural analysis are the vertical traffic load (distributed and point) and the vertical wind load. The bridge is made from borosilicate glass. This type of glass is used to reduce the effect of temperature on the cast structure of the bridge. Additionally, the supports and connections are designed so that they do not restrain deformation from temperature. Furthermore, the shape and place of the connections and supports ensure the possibility of unequal settlement without the formation of unacceptable stresses. Multiple variant studies are carried out. In the first variant study, optimisation is done on several 2D models to determine the best shape for the bridge's final design. The second variant study focuses on the 3D shape of the bridge and how the bridge is split into manageable segments. The final bridge comprises four cast outer elements, one cast keystone, and a float glass bridge deck. The bridge is simply supported on both sides of the canal. The connections and supports are based on compression and friction and use a polyurethane interlayer. The weight of the final optimised bridge is reduced from 32t to 11.2t with a maximum cross-sectional thickness of 210 mm to get an annealing time of approximately one month. Due to symmetry in the design, only one-fourth of the bridge is optimised. During the optimisation, seven different distributed load scenarios are implemented. For the point load, a region is excluded from optimisation. After optimisation, finite element analysis and manual verifications are performed.

Concrete is one of the most widely used construction materials across the world. Although, the traditional construction techniques are being improved for efficiency, cost and material optimization, there are disadvantages as well, such as the use of formwork, highly labourintensive and limited architectural freedom for design and material savings. 3D printing of concrete structures is one of the emerging technologies promising the automation in construction industry. However, 3D printed concrete structures pose higher risks of shrinkage as compared to the conventional concrete structures due to their different construction techniques and material composition. Shrinkage can raise issues such as reduction in strength of the structures, poor durability and aesthetically unpleasant structures. The research aims to study the shrinkage behaviour of the 3D printing concrete mixture in different restrained and curing conditions. Based on the experimental data, a finite element model has been developed to predict the shrinkage behaviour over time. The free shrinkage test was performed on cast samples and 3D printed samples of dimensions 160x40x40 mm3. The specimens were kept in two curing conditions: covered with plastic sheet and (2) uncovered or exposed to environment from the time of casting. The shrinkage behaviour was studied for up to 60 days at relative humidity of 65% and temperature 20°C. A higher shrinkage values as compared to normal and highperformance concrete is observed in both 3D printed and cast samples. The 3D printed samples showed a higher shrinkage of 1518% as compared to cast samples due to the 3D printing processes. Restrained ring test were performed for three curing conditions: (1) exposed to environment, (2) covered with plastic sheet and (3) sealed with waterproof tape. The sample exposed to drying cracked within 3 days followed by covered with plastic sheets in 4 days and the specimen in third condition cracked within 8 days. The experiment indicated that the autogenous shrinkage is so high in the concrete mixture to induce shrinkage cracking. A finite element model has been developed to simulate the shrinkage behaviour of the concrete mixture based on the experiment results of the free shrinkage test of cast specimens. The capillary tension approach has been used as the theoretical framework. It uses the KelvinLaplace equation to calculate the capillary stresses and the Bentz deformation model to calculate the corresponding shrinkage strain. It is applicable for ambient relative humidity of more than 40%. The required input for the model are: degree of hydration over time, elastic modulus and distribution of relative humidity over time. The degree of hydration has been calculated using HYMOSTRUC software. The experimental results of the free shrinkage test for cast samples have been simulated in ANSYS. An inverse analysis has been used to obtain the material parameters required to model the moisture diffusion process. Transient heat equation has been used to model the diffusion process. Since the concrete mixture has a low watercement ratio, the effect of autogenous shrinkage has been taken into account as well. The calibrated finite element model gave an error of 810% as compared to the experimental results. The moisture profile obtained from the model has been compared to an analytical model to validate the model. It shows good agreement, especially for upto 28 days. Finally the developed finite element model has been applied on three case studies to assess the accuracy of the model. First, the restrained ring test has been simulated to validate the model based on the prediction of the cracking time. It showed that to accurately predict the shrinkage induced stresses, the creep and the relaxation phenomenon plays a crucial role as well. Second, the model has been used to simulate the shrinkage in a 3D printed flower pot restrained at varying time. Third, a parametric study has been designed using the developed model. Overall the study concludes that the shrinkage in 3D printing concrete mixture is quite high as compared to the normal concrete even if conventionally cast. The 3D printing processes can increase the shrinkage further. The developed finite element model can be used as a tool to estimate the shrinkage strain.

This research focuses on developing architected lightweight cementitious cellular composites (LCCCs) for potential thermal insulation purposes. Specifically, Voronoi cellular structures with different randomness are adopted and used as cellular structure of the LCCCs. the mechanical properties of the developed LCCCs are investigated by experimental and numerical methods. With the help of 3D printing technique, LCCCs are prepared with two mixtures: a reference mortar, denoted as REF and mortar incorporating microencapsulated phase change materials (mPCMs), denoted as PCM14. Mechanical properties of developed structures are first investigated. The compressive behaviour of the LCCCs is investigated at the age of 28 days. In general, the LCCCs show anisotropic compressive behaviour in two loading directions: the compressive strength and stiffness of the LCCCs in the out-of-plane direction is substantially higher than that of the in-plane direction. Comparing to conventional foam concrete with the same density, the out-of-plane compressive strength of the LCCCs is higher than commonly reported cases in literature. Due to the high porosity of the cellular structures, the compressive strength of the LCCCs is significantly reduced comparing to the corresponding constituent materials, as expected. In addition, this strength reduction of the LCCCs made with PCM14 is substantially lower than the that of the REF samples. Interestingly, the relative stiffness (measured stiffness of the LCCCs normalized by their porosity) of the mPCMs incorporated LCCCs is even higher than the constituent material E-modulus. Furthermore, the critical role of air voids on the compressive behaviour of the LCCCs is identified. The thermal conductivity of the LCCCs is investigated by numerical models using commercial software Abaqus and ANSYS. It is found that the thermal conductivity of the LCCCs is comparable with the conventional foam concrete of the same density. The geometry heterogeneity of the LCCCs has a minor effect on determining the thermal conductivity of the LCCCs. Moreover, increasing porosity or reducing thermal bridge on the heat transfer direction can dramatically improve the thermal insulation performance of the LCCCs. It is found that the natural convection of the air within the cellular pores and the radiation has less notable effect on the thermal conductivity of specimen. Comparing to the REF, PCM14 has enhanced thermal insulation performance. In the end, using extrusion-based 3D concrete printing technique, the LCCCs with mPCMs has been successfully printed as an implement of manufacturing LCCCs as a construction-scale brick. In general, the developed LCCCs have high porosity gives good insulation properties as well as good compressive strength. This gives them great potential to be used as novel lightweight thermal insulation materials for construction.

The outbreak of the COVID-19 virus has increased the interest in respiratory droplet dispersion in the built environment. The dispersion of these droplets is inseparable from transmission risk. Sneezing, coughing and breathing can be modelled in many ways. In this study several models of increasing complexity are proposed and compared.
Three different models are distinguished. The first is a simple ballistic model, where the trajectories of particles of different sizes are simulated, given an initial velocity and particle diameter. This simulation gives a first insight in the movement of particles from Newton’s second law.
Model 2 works by releasing particles in a turbulent jet. Mean properties of turbulent jets have been derived from experiments and computer modelling. By means of particle tracking, the dispersion of three different sizes of particles are monitored. The turbulent behaviour of the jet is captured by applying a stochastic discontinuous random walk model (DRW) in Model 2. The smallest particles (10 μm) are airborne, while the large (100 μm) particles fall out of the turbulent jet and settle on the ground. Medium size particles (50 μm) have the widest range of dispersion. The effect of evaporation has been studied in this research as well. Both relative humidity and relative velocity (the velocity between the surrounding air and the particle) influence the evaporation speed. The medium size particles are affected the most by evaporation. Depending on the ambient conditions, the medium size particles either behave more like the large particles or as the small particles.
The third model contains the effect of an ambient crossflow, representing ventilation flows. Trajectories of bent jets have been calculated. Eulerian solutions for dilution have been found for such bent jets. No mean properties in literature have been found for bent jets and hence the Langrangian particle tracking model could not be used.
Based on the results of model 2 we conclude that ventilation flows will have a tremendous impact on the dispersion of respiratory droplets, in particular the particles with initial diameter 75 - 100 μm. These droplets become airborne and will follow the ventilation flow. In dryer air droplets evaporate faster and will become airborne more quickly.
Future research could be done to create a CFD model to generate analytical formulas for jets in ambient crossflows. More detailed room conditions like the stratification of air temperature can be taken into account.

The airborne transmission of SARS-CoV-2 in educational buildings has raised concerns during the current COVID-19 pandemic. In this study, a portable fog generator system was designed and assembled to visualise the airflow pattern of exhaled droplets in a classroom. The system consists of five components: medium, fog generator, buffer, pump, and manikin head. The medium was made of a combination of glycol and demineralised water, which produced a fog composed of droplets mimicking to some extent human breath. The fog was produced with the fog generator and passed through a pipe into the buffer for build-up. After accumulation, the fog is pumped through another pipe and is exhaled out of the mouth of the manikin. The experiments were conducted in a simulated classroom. The lights of the room were dimmed and six lasers were used to make the fog more visible. Four different ventilation regimes were examined: no ventilation, natural ventilation (open windows and door), mixing ventilation (600 m3/h), and a combination of natural + mixing ventilation. The experiments were recorded with a camera and analysed to determine the horizontal distance of the path taken by the fog and to measure the time it remained visible after exhalation from the mouth. During the experiments, it could be observed with the naked eye that the glycol droplets travel much further and linger in the air for longer than what is captured in the recordings. Furthermore, not all the droplets were visible with the camera, especially the smaller ones of a few micrometres in diameter. The recordings showed that at the natural ventilation regime the droplets travelled the furthest distance (1.8 metres). This wind coming through the door pushed the drops further into the room. The combination of natural + mixing ventilation regime had the highest indoor air velocity, causing the droplets to reach the shortest distance (0.5 metres). In conclusion, the type of ventilation, classroom layout, and exhalation location play an important role in determining the airflow pattern, as they affect how long and how far the glycol droplets travel. Applying any type of ventilation is critical in transmission control and reduces the possibility of aerosol accumulation in the classroom as smaller droplets can linger in the air for many hours until they settle on a surface.