Converged solar reflection resulting from the curved façades of mid-rise and high-rise buildings has proven to be a uniquely dangerous phenomenon, yet increasingly common. The "death ray" incident at 20 Fenchurch St (the "Walkie Talkie" Building) in London in 2013 was mirrored by a similar occurrence at the Amsterdam University Medical Center (AMC) in 2021, where parts of a car melted from the intense heat produced. This reoccurrence raises a fundamental question as to why this problem keep happening. Several factors may contribute: past studies focused on isolated instances, many building engineers and architects are unaware of the risks, and numerical reproduction of this phenomenon involves numerous parameters and complex scripting.
This thesis aims to provide an algorithm to accurately reconstruct the converged solar reflection phenomenon numerically by analyzing various input parameters, such as the geometry of a façade, the nonlinear reflection rate of glass panels, and the effect of anisotropic sky models. To ensure the validity of the model, on-site solar irradiance measurements were conducted in the parking lot of the AMC building. Additionally, the program was used to reenact the phenomenon at the Walkie Talkie building before improvements to its façade.
Results indicate that the three-dimensional problem can initially be approached with a two-dimensional model using horizontal cross-sections of the façade. The angles at which the most intense focal points occur in both the 3D and 2D models of the AMC building correspond to each other, at 15.24 and 23.04 degrees from the optical axis of the façade (solar azimuth angles of 147.34 and 139.54 degrees from the north). The study also concludes that under the same conditions, replacing a quarter-circle-shaped curved façade with a parabolic-shaped curved façade would significantly worsen the effect, potentially leading to five times higher converged solar reflection on the ground.
In the case of the AMC building, the highest recorded irradiance during measurement was 4834 W/m². This value differed by only 13.45% from the 3D model using the Reindl sky model, which showed 4184 W/m². Conversely, the conventional isotropic sky model produced a larger difference of 23.68%. For the 20 Fenchurch St building, the Reindl sky model also produced more intense results compared to the isotropic model, with the focal point intensity reaching up to 6271 W/m² on August 29, 2013. However, limited access to accurate three-dimensional models and details of the surrounding area may have affected the results.
The study also examined the systematic error due to mismatched curvature of the glass panels with the building's curvature. This mismatch caused irradiance variations, increasing by up to 23.52% at one time and decreasing by 13.09% at another, indicating no constant increase or decrease on the intensity of the focal point.
In conclusion, this thesis successfully captures various variable inputs to recreate an accurate converged solar reflection phenomenon in both the AMC and the "Walkie Talkie" buildings. It integrates these variables into one continuous script without the need to switch between different software, providing a comprehensive tool for assessing and mitigating this dangerous architectural flaw.

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.

Glass, a transparent and durable material with significant structural potential, is extensively used for architectural and structural applications in buildings. Existing approaches mostly use float glass, which is confined by planar designs, resulting in two-dimensional facades. Several examples of curved glass applications exist which, due to the limitations of current fabrication techniques, result in repetitive panels. Emerging architectural trends demand more fluid, three-dimensional freeform shapes, which present glass shaping processes cannot provide without incurring excessive costs and material waste in the fabrication process.

Research in other materials shows that flexible moulds are able to produce complex geometrical results. More recently, knitted fabric formworks have proven to be very successful in creating concrete shells of high complexity and low material usage and waste.

This thesis aims to address the gap by investigating the viability of using knitted basalt moulds for glass slumping, a novel fabrication approach that might allow for the manufacture of customizable, freeform curved glass components. The research investigates the possibility of this technology to accomplish extreme geometries while remaining simple and cost-effective in mould manufacture. The methodology of this thesis consists of a thorough literature research, experimental testing and a design application. The literature study investigates and compares present glass curving technologies and also the moulds used for each method to visual, geometrical, structural, and sustainability criteria. Flexible mould applications in other materials are also researched and compared to the ones used for glass.
The second part of the thesis is an experimental exploration. Basalt yarn is chosen to create hand-woven and CNC-knitted moulds to test with glass slumping. The experimental phase involves testing several knitted basalt moulds and combinations with coatings to determine ideal material combinations in order to improve surface quality and geometric precision. After reflecting on the experiment results, experimental data is used to create a final prototype attempting to achieve geometrical control and repeatability to prove the potential of the proposed
fabrication technique.

Finally, the third part of the thesis is a design application. Casa da Musica in Porto is chosen as a case study to recreate its glass façade in a freeform shape. Connection details between the glass panels are designed for the proposed facade design and the proposed fabrication of each panel is showcased.

Crack-width control of concrete structures, a serviceability limit state (SLS) criteria, could be governing in design calculations over ultimate limit state (ULS). To ensure adequate crack-width control, additional steel reinforcement is often used, which, while essential for SLS, is redundant for ULS purposes, thereby increasing the environmental impact due to excessive steel use. In efforts to reduce the amount of steel reinforcement required in RC beams, a series of MSc thesis studies at TU Delft have explored the potential of incorporating a layer of Strain-Hardening Cementitious Composites (SHCC) in the tension zone of beams, creating what are known as hybrid Reinforced concrete/SHCC (R/SHCC) beams. SHCC is a composite material that, through its specific composition and fiber incorporation, exhibits the ability to form multiple fine cracks when subjected to tensile stresses, offering an effective solution for enhancing crack-width control. Huang [1] demonstrated the effectiveness of a 70mm thick SHCC layer in a 200mm high hybrid R/SHCC beam. Singh [2] investigated the role of interface preparation on the crack-width control performance and found that both smooth and grooved SHCC-concrete interfaces provide similar flexural crack-width control in a 200mm high hybrid R/SHCC beam with a 70mm thick SHCC layer. Bezemer [3] explored the effectiveness of a 70mm thick SHCC layer in hybrid R/SHCC beams of more practical heights of 300mm and 400mm, revealing an anticipated decline in the layer’s flexural crack-width control efficiency as beam height increased.

The current study investigates the effect of three key parameters on crack width control: (1) the SHCC-concrete interface, ranging from a smooth interface to a profiled interface coated with Vaseline; (2) the rebar-SHCC bond, weakened by changing from ribbed to smooth rebars; and (3) the SHCC type, varying from PVA-based SHCC to PE-based SHCC. Additionally, the effect of curing time is examined. The beams, with a total height of 400mm and a 70mm thick SHCC layer, are tested experimentally in a four-point bending set-up to generate a constant bending moment region (CBMR), allowing for the study of flexural cracks. Digital Image Correlation (DIC) is performed to evaluate the crack patterns and the crack-widths. The performance of the beams is assessed by checking its capability to restrict crack-widths below the 0.2mm and 0.3mm crack-width limits.

The experimental results demonstrate that the use of a Vaseline-coated profiled SHCC-conventional concrete (SHCC-CC) interface enhances the crack-width controlling ability of hybrid R/SHCC beams compared to a smooth interface. The beam with this profiled interface demonstrates a significant increase in the load, expressed as a percentage of the yield load, at which the 0.2mm and 0.3mm crack-width limits are exceeded of 37.6% and 22.7%, respectively, compared to the beam with a smooth interface. This improvement is attributed to the interface’s ability to show controlled delamination (as a result of the mechanical interlock provided by the shear keys) over the full length of the region of interest (as a result of the chemical debond facilitated by the Vaseline coating).

The use of smooth rebars significantly compromises the crack-width controlling ability of hybrid R/SHCC beams, as the beam with smooth rebars experiences a decrease in the load, expressed as a percentage of the yield load, at which the 0.2mm and 0.3mm crack-width limits are exceeded of 51.0% and 35.7%, respectively, compared to the beam with ribbed rebars. This reduction in performance can be attributed to the weakening of the reinforcement-SHCC bond, which relies solely on chemical adhesion and friction with smooth rebars. This limitation hinders the activation of SHCC and leads to rapid localization of cracks within the SHCC. Despite the application of a Vaseline-coated profiled SHCC-concrete interface in both beams, the benefits of the Vaseline-coated profiled interface observed in the beam with ribbed rebars were not realized in the beam with smooth rebars, indicating that a sufficient bond strength is a prerequisite for effective crack-width control.

PE-SHCC improves crack-width control in hybrid R/SHCC beams compared to PVA-SHCC when used in combination with smooth rebars. The beam with PE-SHCC exhibits an increase in the load, expressed as a percentage of the yield load, at which the 0.2mm and 0.3mm crack-width limits are exceeded of 6.1% and 14.9%, respectively, compared to the beam with PVA-SHCC. This improvement can likely be attributed to the larger ductility of PE-SHCC and the superior reinforcement-SHCC bond strength in PE-SHCC, which facilitates greater activation of the SHCC. However, it remains uncertain whether these findings can be extended to the use of ribbed rebars, as the superior reinforcement-SHCC bond strength in PE-SHCC may lead to a excessively high bond strength which could hinder strain redistribution.

The experimental results also demonstrate that curing time significantly influences the crack-width controlling ability of hybrid R/SHCC beams, with the beam tested at a later age (85 days of SHCC age) showing superior crack-width control compared to the beam tested by Bezemer [3] at 55 days of SHCC age. Specifically, there is an increase in the load, expressed as a percentage of the yield load, at which the 0.2mm and 0.3mm crack-width limits are exceeded in the beam tested at 85 days of SHCC age of 10.6% and 5.5%, respectively, compared to the beam tested at 55 days of SHCC age. This improvement is attributed to two factors: (1) the tensile properties of SHCC degrade over time, delaying crack localization, and (2) the SHCC-CC interface bond strengthens over time, resulting in less pronounced delamination. Consequently, while less SHCC is activated, the ability of SHCC to serve as effective reinforcement is enhanced.

In conclusion, the current study demonstrates that crack-width control in hybrid R/SHCC beams can be significantly improved by employing a roughened interface and utilizing ribbed rebars instead of smooth rebars when working with PVA-SHCC. Additionally, when using smooth rebars, opting for PE-SHCC enhances crack-width control. The current study also shows that hybrid R/SHCC beams of more practical height can effectively control crack-widths beyond reinforcement yielding when implementing the proposed design adjustments.

Problem definition: In the car park industry, a new trend has emerged, shifting the demand for parking from permanent one-of-a-kind parking structures towards temporary modular structures (Drenth, 2020). Meanwhile, the building industry faces a transition into a more sustainable industry. This requires rethinking of the design process, taking into account possible reuse of a building or its elements as well as potential use of different materials. Timber is a renewable material and as a result of developments in timber engineering, now allows the construction of taller and larger structures. Given these trends and challenges, the objective of this thesis is to provide a structural system proof of concept for a temporary multi-storey car park, using timber as primary structural material.
Approach: A broad literature study provides background information on the various relevant topics and is followed by a refinement of the objective, substantiated by two sub-studies. This has resulted in two sub-goals: the minimization of total deck height (< 700 mm) and minimization of the structural systems weight (column load < 1,000 kN). A proof of concept is developed through a parametric study with structural validation into four main design variants (consisting of a deck and framing system), for which the effect of altering four geometric parameters (parking deck span, use of struts, distance between columns in transverse direction and minimum distance between joists) on these sub-goals is studied. Furthermore, a sensitivity analysis is performed on the effect of altering the requirements concerning fire-safety, vibrations and deflections on the deck height and weight. Finally, the proof of concept’s performance is compared to five alternative modular and/or timber car park concepts in a case study.
Evaluation: It is concluded, that design variants using long-span deck systems result in a relatively small deck height, but high self-weight. A CLT rib deck should be applied under “standard” assessment criteria, but significant reductions in deck height (31%) and weight (49%) can be achieved by using LVL rib decks when vibrations are not considered and deformation limits are increased. The total deck height of design variants with short-span decks, which use solid LVL panels, highly depends on the supporting framing system, but its self-weight is roughly halve of the long-span design variants. The effect of alternative assessment criteria on design variants with short-span decks is rather limited. It is concluded that the use of struts significantly reduces the total deck height (17-30%) and structures weight (5-11%) and a transverse column distance of a single parking bay width is preferred. The distance between joists is of less relevance, but a bigger parking deck span increases both deck height and total weight.
The resulting proof of concept consists out of a short-span solid LVL deck system, which spans two times 2.5 m (single parking bay width). It is supported by glulam main girders, spanning the entire parking deck, which are simply supported by a set of columns at a transverse distance of 2.5 m and are additionally supported by slanted struts between the columns and main girders.

The results from the case study show, that the total deck height of the proof of concept (666 mm) is smaller that the sub-goal of 700 mm and comparable to alternatives with decks made of steel, concrete and GFRP. Furthermore it is 40% thinner than the alternative in timber as a result of the use of LVL and struts. In terms of weight, the use of timber is much lighter than using concrete decks (<25%) and only 17% heavier than the extremely lightweight GFRP decks. Furthermore, it results in the smallest loads on the foundation (678 kN which is smaller than the sub-goal of 1,000 kN). A first extremely simplified durability analysis on amounts of embodied carbon in the main structural elements indicates timber has significantly lower amounts of embodied carbon in comparison to the alternative concepts.
Implications: Based on the results presented, it is concluded that timber is applicable for almost all main structural elements of a temporary and modular multi-storey car park. The case study has shown that the proof of concept can compete with alternative modular car park concepts in terms of deck height and outperforms most alternatives in terms of the structures weight. It is also indicated, that timber has the potential to significantly improve the performance of a structure in terms of sustainability.
For future research, it is advised to further develop the proof of concept, focussing on the connections and durability risks and study the incorporation of circular design strategies into the design and construction process of the proof of concept. Furthermore, alternative assessment criteria should be validated. Finally, it is advised to study the potential use of other innovative sustainable building materials like BauBuche and make a detailed LCA study assessing the performance on sustainability.

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.

For the first time since the 1970s, concrete plans are in motion to bring humans back to the Moon through the Artemis programme. The dawning era of space exploration aims to set the groundwork for long-term off-Earth settlement, with sights on bringing the first humans to Mars. In order to provide a safe means of inhabiting extraterrestrial (ET) environments, a self-supporting habitat shield concept has been developed by the Specialist Modelling Group at Foster + Partners, which is based on the use of mechanically interlocking masonry manufactured from in-situ resources. Significant progress must still be made in the structural design and validation of such systems, however, before they can be safely implemented. Due to the novelty of the proposed structure, existing research does not provide numerical evidence of its stability under self-weight, or under seismic loading. Research in this direction is valuable, as it explores alternatives to popular design concepts based on monolithic additive manufacturing and addresses research gaps related to the analysis of mechanically interlocking structures.

The aim of this project is to provide novel insight into the stability of self-supporting dry-stone vaults under the influence of microgravity and ground motions. This is achieved through a three-part analysis approach, which starts with an investigation into the fundamental structural behaviour of dry-stone, Nubian-type vaults based on a series of parametric studies. Key geometric parameters of the vaults are varied, and the resulting distinct element models are subjected to quasi-static pushover-type analysis in 3DEC. The parametric studies indicate what configuration of the vault geometry can maximise seismic capacity. This optimal vault geometry is modelled in Rhino using geometric constraint solving, which is used to produce a model which can be assembled from mechanically interlocking components. Through pushover-type testing and dynamic time history analysis, the performance of the resulting vault model is assessed with respect to possible moonquake loading. The final part of the design process accounts for uncertainties in material properties by conducting sensitivity studies, which indicate what degree of variation in performance is possible.

After completing the three mains sets of analysis needed to design a moonquake-resistant vault, several comparative analyses are carried out to provide context to the structural performance of the Nubian-type vault. The first of these additional investigations models an equivalent monolithic vault geometry in DIANA and conducts finite element analysis to determine its capacity for lateral acceleration. The second comparative study determines how covering the vault in loose regolith may influence its structural performance. The third study investigates how the variation of gravity affects the stability and seismic performance of the vault.

Several key findings are obtained in this project, leading to an understanding of the structural behaviour of Nubian-type vaults and how they may be a possible solution to shielding demands in ET contexts. The final vault model was shown to remain stable under a uniform lateral acceleration equivalent to the PGA for a possible moonquake with a 475 year return period. Dynamic analysis conducted using an artificial ground motion record obtained for the same return period produced less favourable results, resulting in partial collapse of the outermost six courses of the vault. Computational constraints necessitated the implementation of an undamped analysis, however, so these results are considered to be conservative. Further analysis is needed, but these results suggest that with minor adjustments, the vault may be able to safely resist moonquake loading. The comparative monolithic vault analysis demonstrates that an additively manufactured vault may provide slightly better resistance to static lateral acceleration than a component-based vault. When considering the structural redundancy and energy dissipation necessary for safe seismic design, however, the discrete vault is expected to perform better. Results show that covering the vault in loose regolith is expected to reduce its overall stiffness. Conclusions about changes in stability cannot be made with confidence due to modelling issues at the interface between the regolith and the structure. By studying the influence of gravitational variation on the vault, results indicate that it may perform favourably on the Earth or on Mars, though the possibility of material damage must be studied further.

The importance of joints in timber structures is strongly emphasized in the existing literature (e.g., Blaß & Sandhaas, 2017; McLain, 1998). The aim of this project is to provide insight into whether the cross-sectional sizes of the member are dictated by the dimensional sizes of the laterally loaded dowel-type connection or the strength and stiffness requirements of the member itself in timber frame structures.

In this research project, a parametric study is performed. The parameters in this study represent the global frame structure and the laterally loaded dowel-type connections. Together, these parameters form a parametric model that lays the foundation for the tool that is constructed in this study. This tool is built in order to generate a number of unique configurations that fulfill the design verifications. Using the tool, two analyses are performed. In analysis 1, the effect of different distances between the secondary beams is examined. In analysis 2, the effect of different grid sizes of the column in the frame structure is studied. In both analyses, two member sizes are first selected based on the criteria 'lowest cross-sectional area' (LCA) and 'lowest height beam' (LHB). These two member sizes form the starting point for generating different configurations of laterally loaded dowel-type connections.

In this research project, three factors are found to contribute to the largest reduction in the number of unique configurations for all constructed cases examined in analysis 1 and 2. These three factors are small column widths combined with high shear forces, the effect of a 'compact' member, and the effect of 'brittle' failure mechanisms on the LCA-members, which was selected as a design constraint in this study. These factors may be relevant for engineers to take into account when designing the structural members.

However, in this study, no constructed case is found in which the member needs to be redesigned in order to fit the connection. This means that one can conclude that the dimensional size of the structural member is dictated by the strength and stiffness requirements of the member itself. Important to note is that, although a large number of parameters was incorporated into this study, not all potentially relevant parameters were taken into account. When incorporating factors such as the horizontal forces in the connection, the effect of shrinkage and swelling, the level of difficultly in terms of assembling the joints on site, and adjustments to guarantee a certain level of fire resistance, certain turning points in the dimensional interaction between joints and members may be found.

Finally, beyond allowing for the dimensional interaction between joints and members to be studied, the tool constructed in this study is also valuable to practical engineering. The large amount of data that is generated by the tool allows the engineer to explore the different possible configurations in the process of designing joints. By connecting the output of the tool to the Design Explorer interface, the engineer has the opportunity to search through all the individual characteristics or a specific range and examine different possible connections in an efficient manner. One of the main contributions of this research project, therefore, lies in the tool itself.

Space frame structures today are a common choice of load bearing system for achieving long spans with minimal interruptions of the floor plan beneath. On top of that, the versatility of space frame structures to conform to any shape makes them particularly interesting today, especially in the context of free-form geometry which is becoming ever more common. In structural design, and especially for space frame design, the creation of a structural model is quite a labour-intensive process, and it is highly beneficial to automate the structural model generation. Furthermore, the design of such structures can benefit from an exhaustive preliminary design space investigation. Thus, this MSc thesis deals with the parametric design, engineering and optimization of space frame structure typologies based on different initial surface discretization of the input free-form surface geometry, and different topological relations of space frame top and bottom layers. These topological relations are based on Conway operators most relevant for the structural patterns occurring in space frame structures specifically, dual, kis and ambo. These operators are always applied on an initial or seed meshing of the desired free-form surface, to create different space frame layouts for them to be compared by their structural performance, primarily in terms of mass. The scope of initial meshing options is kept to tri, quad, and skeleton-based quad meshing. These three different types of mesh options, combined with the three possible Conway operator options, constitute the main nine combinations for each case study example.
In essence, every space frame design, due to the linear and geometric nature of the structural elements (nodes and bars seen as points and lines), can be considered as a literal structural translation of the final desired free-form shape. This free-form shape is always tessellated or discretized in certain configurations. The aim was to gain more insight into how the initial tessellation affects the behaviour of space frame structures as well as how the process of optimization of such structures is influenced regarding the initial tessellation. To gain insight into this influence qualitatively and quantitatively a parametric tool was developed to conduct case studies. The tool allows for the generation and cross-section optimization of various space frame structures based on an input surface. This parametric tool was developed using Rhino, Grasshopper, and karamba3D structural analysis plugins for grasshopper.