During the early stages of the construction process of a building, the potential impact of design decisions is at its greatest. One of the reasons is the lack of computational tools at these stages. The main objective of this research project was the expansion of StructuralComponents by the development of a parametric real-time computational tool prototype to quickly determine the feasibility of mid-rise buildings designs with rigid frames as stability members. A study of rigid frames behaviour was performed to define a range of applicability of the existing analytical representation and to develop two new methods to analytically represent rigid frames behaviour: a correction method for the shear beam representation and a method based on the Timoshenko beam theory. To allow for vertical connections of different rigid frame geometries, an analytical method to consider a different stiffness along the height was developed. The results showed that the analytical shear beam representation of rigid frames has a reduced range of applicability for parametric purposes. This reduced applicability is due to the combined shear and bending behaviour. The correction method follows from the prediction of the error when using the shear beam representation. In addition to the correction of the shear beam representation, the prediction of the error was defined as a parameter to classify the behaviour of a rigid frame as a shear, flexural or combined type. Both, the applicability range and the correction method are based on analytical and numerical comparisons, as well as the performed validations. The implemented software comprises Maplesoft to get the analytical solutions and Grasshopper with Karamba3D (which contains the finite element solver) to get the numerical solutions. The method based on the Timoshenko beam theory comes from the theoretical derivations of a serial system that takes into account both, bending and shear deformations. It was found that it is more appropriate to analytically represent the general behaviour of rigid frames with the Timoshenko beam theory and by additionally considering a different stiffness calculation for the ground floor. Also, it was shown that the vertical connections of rigid frame geometries can be addressed with the calculation of an analytical solution for each different geometry along the height. Both analytical approaches, the Timoshenko beam representation and the method for vertical connections were implemented in the tool prototype. Such a tool consists of a calculation method to assess the structural performance of a building by the simultaneous structural analysis of every rigid frame subjected to a lateral load. The three main characteristics of the tool prototype are the parametric adaptability, the instantaneous display of results and the stacking “Lego-type” connection between components. The validations in this research project showed that the proposed and implemented methods are suitable for preliminary design stages because the error for the most unfavourable geometric configurations resulted in less than 15 percent. It is recommended to conduct further research and tool development. In so doing, more informed decisions can be made during the preliminary design stages.

The Netherlands is currently in the process of transitioning from a linear economy to a circular economy, in accordance with the ”Nederland Circulair 2050” policy. To increase the circularity of buildings, several approaches can be integrated. In this research, the so-called Design for Deconstruction and Donor Structural Framework concepts are elaborated as possible approaches. The first concept focuses on taking the future de- and remountability of a building into consideration during the design process. This concept allows buildings that approach their end-of-life phase to be (partially) reused as structural components, on a new location. The second concept can be applied during the construction phase of a building, where structural components of an old building are dismantled and reused in the to be constructed building. The difference between the two concepts thus being the life cycle in which they are applied. Therefore, the resulting benefit of using a Donor Framework can be seen immediately, whereas the benefit of applying the Design for Deconstruction concept can only be stated in the future. Unfortunately, the current procedure to measure the sustainability score of a building, the Life Cycle Assessment methodology, does not take these concepts into account. This makes determining their impact on the environment hardly possible. Also, due to the fact that detailed information about a design is required, a Life Cycle Assessment is made only once the design is final. In this order, all design variables are set such that designing towards sustainability is not an option. This research focuses on solving the introductory problems and aims to enable sustainable material choices for a structural design possible in the early design phase. Both the Donor Structural Framework and the Design for Deconstruction concepts were taken into consideration. This main goal has been split into two sub–questions:- How to assess the environmental impact of a steel, concrete and timber load bearing structure in the early design phase? -How to implement the Donor Structural Framework and the Design for Deconstruction concept into the existing Life Cycle Assessment methodology? The research questions have been answered by executing the following approach: 1.A parametric model is used in which not only the geometry and structural calculations are included, but the Environmental Impact Calculation as well. In the event of a design change, the Environmental Impact Calculation is automatically reiterated, which means different designs can be compared quickly based on their environmental impact. The model constructed for this study is suitable for designs in steel, concrete and timber. For each material a reference design is created. The Bill of Materials of these designs serves as input for the Environmental Impact Calculation on which the materials were compared in a later research phase.2.First, an existing end-of-life allocation method has been adjusted to include reuse during both the construction phase (Donor Structural Framework) as the end-of-life phase (Design for Deconstruction). Secondly, the Building Circularity Index, which recognizes a ”circularity score”, has been implemented in this method. In this study the Building Circularity Index is assumed as the ”probability of future reuse of the building”. The modified method was implemented in the parametric model to enable a real-time Environmental Impact Calculation. This approach has been fully implemented into a parametric visual script, executed in the Grasshopper, a parametric environment plugin of Rhino which enables visual scripting. Input parameters are imported from Excel, the Grasshopper script calculates the environmental impact and exports the results to Excel where they are visualized in a dashboard. Ultimately, the developed parametric model has been divided into a part containing the geometry and structural calculations of the reference designs and a part where the newly developed Environmental Impact Calculation method is implemented. Combining the results of both parts in the total model, it becomes possible to assess whether a design is best built in a certain material in the early design phase. The final model can provide results with or without the use of a Donor Structural Framework and with or without application of the Design for Deconstruction concept. For the purpose of demonstrating the functioning of the model, a reference design in steel, concrete and timber was implemented as a basic geometry. This geometry was assumed equal across all designs and for comparability purposes, dimensions were fixed. Consequently, it can be concluded from the results of these reference designs that using a Donor Structural Framework results in a lower environmental impact than applying the Design for Deconstruction concept by maximizing the remountability of a structure. Until a lifespan of 75 years, using a timber donor framework is the most sustainable solution for the reference design. From 75 until 100 years this is the case for steel and from 100 years onward, a concrete design, whether or not using a donor framework, results in the lowest environmental impact. In the current design practice of a building, the default lifespan has been determined by the function of the building (Functional Service Life). By using the model developed here, this lifespan can be determined on the basis of sustainability requirements instead of functional requirements. The differences in environmental impact for different lifespans can easily be compared. Therefore, it is made possible to steer towards a certain lifespan, in order to determine the most sustainable construction based on the clients requirements. This is currently not possible in the Dutch construction industry. However, these results do have their limitations, as they should not be interpreted as general but rather specific conclusions. The following points of attention apply: -Results should not be interpreted as general results, but these results only apply on the three reference designs as elaborated further in the research. These reference designs are not optimized for every material used. -Changing input parameters can have a significant impact on the results. In addition, a number of important parameters (reuse percentage, material lifespan etc.) have been assumed due to insufficient existing research. -The developed allocation equations include the incineration of timber too favorably. This results in a significant deviation in timber environmental impact for lifespans much shorter than 75 years. This flaw can be either due to the model, or the impact parameters as stated in the NIBE EPD app. Lastly, it is recommended to further research the assumed parameters in this research, especially the material lifespan and the incineration impact parameters. As these parameters can have a major impact on the environmental impact of a specific design.

Façades within the building industry ore one the most important and expensive aspect of a project. They are the outer skin of a structure and are responsible for improving energy efficiency, while being both innovative and attractive. At the same time, façades need to accommodate requirements to withstand the outdoor environmental conditions. To meet all of these requirements, there is need for designers to either have knowledge on the different subjects, such as human comfort, sustainability, stability, among others; or work together with different specialist to achieve an ideal design. Following a traditional design process, once the conceptual design is defined it goes through an iteration process between designing and detailing before reaching the manufacturing stage. This process, even though is already considered within the planning of a building, is highly time consuming. Considering this process, the idea of bringing the manufacturing knowledge into the early design stages to speed up the design process was taken into consideration. The idea of bringing the manufacturing knowledge upwards in the design process would help designers, focus only on designing, while the considerations for product availability and manufacturing possibilities are already taken into account. On the other hand, the increasing use of parametric modeling to improve building solutions, has been a growing field. In regards to façade design, the inclusion of free form architecture in the building industry has pushed the need for innovative solutions. It has been proved in these projects that the use of parametric modeling highly increases the speed in which designs are developed. However, the need to adapt existing products and manufacturing techniques to these complex geometries, generates more iteration times and increases the costs of the final product. Now, imagine that not only the available products are adapted to the conceptual designs proposed, but that these designs include from their conceptual stages knowledge acquired from previous experience. This would help avoid the iterations between designers and manufacturers, plus would improve the possibilities of generating a bigger amount of modularity in the design process. With these considerations, the proposal for this project aimed to develop a proof of concept tool that would be capable of encoding a manufacturers knowledge in a digital model, and use it to design a façade that is almost ready to manufacture. For this purpose, the knowledge and information from the façades manufacturer Vianen Kozijnen was used as base for the development of this tool. Once this was established, the modelling phase for the façade design tool begun. Initially the input parameters were set, the knowledge is gathered from the company's input, allowing the designer to set up a model within the possibilities of the manufacturer. In the back end of the tool, the build-up of the main modular panel is generated. Four main variables were defined to generate the geometry of the panel and these are determined by the input parameters. Next, with a finalized panel design, the testing phase is set in place. This phase was divided into two processes. First, the replication of the panel throughout an entire façade. This process begins with a conceptual shape that will be filled with the already designed panel. The results from this process determine the total amount of modular panels and the percentage and amount of customized panels needed. Secondly, the panel is tested for Building Physics aspects relevant in early design stages, which for this case were daylight and sound proofing. The tool then with the geometrical parameters given, includes simulations for both daylight and sound proofing. The results obtained, give information on the performance of the design. For daylight simulations, the results given are for daylight autonomy and daylight factor; and for sound proofing the results obtained give information on the insulation value of the façade, sound proofing of the structure and typical sound proofing. Both results, are information that is useful during early design stages, and can help shape the final project. To test the functionality of the tool, the Sluishuis building was taken as a case study and the tool was applied to design and test one of the façade surfaces of the building. The results obtained through this case study led to conclude the feasibility of encoding manufacturing knowledge. It was determined that as a proof of concept approach the tool generates almost immediate results that include the knowledge needed for manufacturing. However, to be applied into a real project further improvements need to be made; with more focus on, first, being able to apply the tool to a completed building and secondly, include more manufacturers knowledge to generate a library of possibilities; making it useful in real life projects.

The objective of this project is to devise and develop a design tool that lets the user explore different force flows during conceptual design, with the goal to inform different geometries, thereby realizing an integrated design process. Key characteristics that this tool must incorporate to be successful are defined as feedback (the ability to provide rapid and reliable analysis results), guidance (the ability to guide the user towards better designs), design freedom (the ability to allow users to make their own decisions and use their own expertise) and structural overview (the ability to make the general structural behavior clear instantly). Graphic Statics has been identified as a suitable method to model and compute the force flow with, and has been incorporated as the base of the tool. A workflow has been devised where the user first identifies and investigates a design problem manually, creating an initial design that must be used as input for the tool, which includes a definition of joints, members. loads, supports and certain boundary conditions. Due to the nature of Graphic Statics, this initial design must be statically determinate. The tool has been developed for Grasshopper, a parametric and associative modelling plugin of Rhinoceros, which provides a platform that meets the defined development criteria of accessibility, real-time modelling, geometric flexibility, extensibility, and presentation independence. The developed prototype bearing the name of GSDesign consists of custom components scripted in C# containing the main functionality, as well as Grasshopper clusters for specific visualization sequences. GSDesign facilitates the design of 2D truss-like structures, which can be interpreted as force flow designs, whose efficiency is quantified in the total load path. Feedback is generated in real-time, and is presented in a force diagram, form diagram, unified diagram, and/or as numerical values, providing precise and accurate results. Guidance is incorporated intrinsically through Graphic Statics, but also by the incorporation of an optimization process using the total load path value and the genetic optimization component Galapagos native to Grasshopper. Design freedom is ensured through the general setup of the tool, which allows for maximum utilization of the design flexibility that Grasshopper offers. The tool provides a clear structural overview through the visualizations that characterize Graphic Statics, which can be customized to preference by the user. A user experiment has been set up to test the functionality and workflow of the tool in a simple design case carried out by structural engineers to ensure its practical value. Eleven participants were asked to first create an initial design by hand, and subsequently reproduce that design in GSDesign and improve it with optimization. The use of GSDesign visibly led to new insights towards more efficient structural forms, which was supported by an average drop of 31% in structural material volume when comparing the fitness data of the optimized design with the initial design. Also the participants on average rated their own optimized design more than 40% higher on structural efficiency than their initial manual design, importantly without compromising on practical feasibility.

There are two main challenges in the construction industry: carbon emissions and densification in cities. Timber high-rise might prove as a suitable solution to both these challenges. However, there is a lack of implementation of timber high-rise. This research argues that a lack of thorough analysis of timber design alternatives in the conceptual design phase results in the exclusion of further evaluation of timber building designs. This research aims to analyze timber building design alternatives more thoroughly by the development of a tool, based on the Multidisciplinary Design Optimization (MDO) method. In Grasshopper, a parametric model is created with which timber building designs are generated, validated, and optimized. Two main optimization objectives and two constraints are considered in the tool: Firstly, the structural constraint: Each building must be designed according to the constraints as determined in the Eurocode. Secondly, the architectural constraint: Each building must satisfy the architectural design requirements for acoustics, building height, and daylight entrance. Thirdly. the environmental objective: minimize the shadow costs, which are determined according to the MPG methodology. The MPG methodology uses Life Cycle Analysis data to assess the embodied energy impact of structural materials. This embodied energy impact is expressed in shadow costs. Lastly, the economical objective: minimize the construction costs. Based on the mentioned constraints, the tool aims to indicate the design situations in which timber high-rise can be competitive to an assessed concrete design alternative, considering the combination of properties for shadow costs and construction costs. By research and development of the Multidisciplinary Design Optimization tool and analyzing two case studies, a conclusion can be made. Two concrete buildings, which are based on a current Arcadis project, are used as case studies. Both concrete buildings represent a design situation. The main difference between these design situations is the building dimensions. Building A3 represents timber building designs that are created for a design situation with a floor area of 28.8 x 28.8 m and a height of 60 meters. Building B3 represents timber building designs that are created for a design situation with a floor area of 21.6 x 43.2 m and a height of 50 meters. For both case studies, an optimization will obtain timber building designs with an optimal combination of properties for shadow costs and construction costs. This resulted in the following results. For the design situation based on the concrete building "The Rectangle", the Pareto optimal timber building designs, referred to as Building B3, were found to be competitive with "The Rectangle". For the other analyzed design situation, the Pareto optimal timber building designs referred to as Building A3, were not found to be competitive with the concrete building "The Square". Considering the boundary conditions and scope of this research, it can be concluded that a design situation with a rectangular floor plan is favorable over a design situation with a square floor plan and a design situation with a building height of 50 meter is favorable over a design situation with a building height of 60 meter. Also, based on analysis of the case studies the following conclusions were made. Firstly, when the effect of carbon sequestration is excluded in the calculation of shadow costs, the use of timber and concrete in the structural system was found to generate comparable results considering their shadow costs. The inclusion of the effect of carbon sequestration during the lifetime of a timber building results in a reduction of shadow costs of approximately 40% compared to a similar concrete building. Secondly, considering the boundary conditions and scope of this research the ULS is found to be normative for a slenderness up to 2.35. When the slenderness is greater than 2.35, the along-wind acceleration was found to become normative. Next, for all Pareto optimal building designs, the ULS check was found to be normative over the SLS check. Lastly, the mass of the Pareto optimal timber building designs was found to be approximately 8 times smaller than their respective concrete design alternatives, resulting in a foundation with less construction costs and shadow costs.

Cement production is responsible for 8% of the anthropogenic CO2 emissions [1]. Reducing this share will be a strenuous task as the global population and urbanization rates are increasing and, therefore, the need for concrete will remain high [2], [3]. Simultaneously, despite the alarming statistic, a vast majority of demolished concrete buildings are structurally sound [4]. Therefore, this thesis aspires to push beyond the abundance of new concrete and outlines a design workflow for using reclaimed concrete. To enhance the material savings, the workflow focuses on double-curved, compression-only structures that benefit from the principles of structural geometry. To implement the workflow, a novel stacking algorithm is designed using COMPAS [5], an open-source Python framework. It positions quadrilateral voussoirs on a funicular geometry’s thrust surface in a sequential one-by-one manner. The placement is guided by three global design principles. First, a pair of opposing voussoir sides are aligned parallel to the force flow while the remaining pair, which represents the load-transferring faces, is aligned perpendicular to it. This is done to prevent sliding failure. Second, the thrust surface is confined within the middle third of the voussoir to prevent the formation of hinges and cracks. Third, voussoirs are cut into hexagonal shapes and staggering is ensured among neighbouring voussoirs to create an interlocking geometry. Once a structure is completed, its stability is ensured by finding a compression-only equilibrium using the Rigid Block Equilibrium method [6]. The algorithm is then studied using various stocks with different voussoir dimensions of both regular and irregular side lengths, various deployment strategies that enable the user to customize the launch of the algorithm, and different thrust surface shapes. It is primarily assessed what fraction of the initial concrete volume can be retained in the structure. It was found that on average 47% of volume per voussoir is retained and that voussoirs of regular dimensions retain approximately 5% more of the initial volume. Minor differences exist in the results among different thrust surfaces with shapes of more uniform force flow retaining more concrete. Furthermore, smaller voussoirs mostly sized 0.7x0.7x0.2m required 20% less volume to construct a shell than a stock of 1.0x1.0x0.2m voussoirs. At the same time, the smaller stock required almost double the amount of voussoirs, thus, indicating competing goals that require the decision-making of the designer. Next, high-level waste minimization was performed by checking if offcuts could be used to create other voussoirs from the remaining structure or if they could be returned to the stock for future placement. A pessimistic and an optimistic scenario were studied and it was found that 70-85% of the initial voussoir volume can be efficiently retained within the shell and the stock. These results served as the basis for reflecting on how the stacking algorithm influences the suggested workflow by bringing design and fabrication-specific constraints to an earlier design phase. It is described that to improve the retained volume the designer can, first, alter their way of deploying the algorithm, second, modify the input geometry, third, custom select what stock is used for placement, and, fourth, inform the contractor of the level of detail to which a building should be deconstructed and post-processed. Thus, a designer is brought closer to the construction process, and incentives for a more collaborative cross-disciplinary workflow are outlined. Finally, suggestions are made on how to improve the functionality and efficiency of the algorithm. The primary conclusion made is to expand the criteria based on which a voussoir is selected for placement. An emphasis is directed towards using criteria such as distance-to-staggering, local radius of curvature, local force flow, and dimensions of the surrounding voussoirs to limit the offcuts that will be created to ensure complete tessellation. Overall, this study provides a workflow that is enabled by a stacking algorithm. It outlines how to design double-curved, compression-only structures and how their design can influence the entire workflow.

The construction industry has undergone a profound transformation in recent years, driven mainly by integrating advanced digital tools. One such tool is configurators, advanced digital platforms that enable the integration of diverse knowledge domains, allowing architects, designers, fabricators, contractors, and engineers to explore many design variations and assess them against various parameters such as sustainability, cost, and manufacturability. However, Building Information Modelling (BIM) stands out as a game-changer, revolutionising how stakeholders collaborate and execute projects. Generally, a building configurator is made for product-specific criteria involving only one stakeholder. As to developing a multi-party configurator, this research delves into the transformative role of configurators in streamlining design workflows and enhancing collaboration among stakeholders in the construction sector. The Design-Bid-Build (DBB) system, a predominant project delivery method in construction, operates under a linear workflow where the design and construction phases are distinct and sequential. During the bidding phase of this system, once the design is finalized and approved, it is put out to bid, inviting contractors to submit their proposals. To formulate their bid, contractors review the design documents and calculate the overall cost, considering labour, materials, overhead, and profit. This phase is characterized by competitive bidding, where multiple contractors vie to offer the most cost-effective solution to secure the project. This method allows owners to select a contractor that best aligns with the project’s budgetary and quality requirements. In a conventional design workflow, the conceptual design undergoes numerous iterations of design and detailing before advancing to the fabrication phase. This iterative cycle, albeit integral to building planning, is notably time-intensive. Given this context, integrating manufacturing insights early in the design phases has been contemplated to expedite the overall design workflow. Given the considerations above, the project’s proposal was focused on creating a prototype tool capable of executing the competitive bidding process involving contractors and subcontractors. It also translates the manufacturer’s expertise into a digital model. The example of the curtain wall system as a prototype was chosen and modelled as a solution to the proposed workflow. As an assumption, Two curtain wall systems, stick and unitised, are built by two fabricators. This proof of concept would enable the design of a curtain wall façade to be ready for the schematic phase after the bidding. The foundational knowledge and information for developing this tool were sourced from the literature survey. The tool entered the modelling phase after the initial study of design workflow and façade elements. The configurator aimed to highlight the tool's user and developer and their impact during the modelling. The initial step involved setting the input parameters, using the knowledge from the manufacturer needed for the bidding, enabling the designer to create a model that aligns with the manufacturer’s capabilities. Two bidding fabrication-aware configurators were formulated based on the tool's back end. Following the development of the two configurators, the project advances to the validation phase, structured into two distinct processes. Initially, the process was tested for its feasibility and workability of the configurator by various iterations of the input parameters. The outcomes of this process ensure the critical support requirements for the proof of concept. Subsequently, the emphasis shifts to the professional validation of the configurator, a crucial step in the practicality of the solution. Four key validations were analysed in this step with professional feedback from the demonstration. The derived results offer insights into various aspects of the design’s effectiveness, productivity, functionality and market viability, providing pivotal information that can significantly influence the refinement and finalization of the project. The validation results are instrumental in making informed adjustments and optimizations, ensuring the proposed design workflow meets the intended objectives and specifications. Adopting configurators in the construction industry is instrumental in addressing the challenges of increasing design complexities and the demand for sustainable, high-performance buildings. By providing a platform for real-time feedback and multidisciplinary collaboration, configurators allow for informed decision-making, optimizing designs for human comfort, environmental impact, and structural integrity. The exploration of configurators in this paper underscores their significance in advancing digital design workflows and highlights their potential in shaping the future of construction, marked by innovation, sustainability, and enhanced interoperability.

In recent years the AEC industry has started implementing more new technologies. Still, the adoption process is slow. One of the crucial steps during the building designing is a justification of design according to previously defined requirements. That process is still manual to a large extent, therefore unnecessarily time-consuming and prone to errors. The need for automation of requirements compliance checking has been rising in recent years, and the science community presented various approaches for automation. Still, most of the proposed methods has similar problems: using a black-box approach, require that the designer is highly skilled in programming, focusing on only geometric requirements and not covering whole process of compliance checking. Therefore, there is a need for a new approach that can solve all these problems. The rise in popularity of parametric design and tools like Grasshopper opens the possibility to overcome some of the current limitations. Also, the possibility of using requirements management software to have the process fully organized supports the belief in automating compliance checking. The fundamental objective of this project is to explore the possibilities of automating the requirements verification for a building design by using requirements management software to systematically structure the requirements and Grasshopper to generate the rules, which afterwards can be verified. To achieve this objective, the project was divided into three main parts. First, the conceptual framework for automated code checking is developed. Afterwards, the system architecture of the prototype tool was explored, and instructions for scripting the tool were given. Finally, after the tool was scripted, it was tested on a real building model. From the literature review the two main types of requirements are found, the functional and performance requirement. Since the functional requirements are qualitative and cannot be quantified, that category is not suitable for checking with the approach proposed in this project. Therefore, the focus was on performance requirements. The central part of the project is the creation of a framework for automated compliance checking. The five steps are defined and these are: 1.) Requirements defining and logical structuring into RMS 2.) Interpretation of requirements 3.) Building model preparation 4.) Checking phase 5.) Reporting phase After the theoretical basis is set, the modelling of the tool is elaborated. Firstly, the requirements for the tool are set. Afterwards, the system architecture is explored, and finally, instructions for scripting the tool are developed. After the prototype tool is scripted, it is tested on a real building model, and it shows clear advantages compared to other approaches or manual work, still, it also has some disadvantages. Test of the tool proved that the Visual programming language environment is a great platform for developing a white-box approach for automated compliance checking. Also, testing on the real-world building model shows that a five-step approach for automated testing of building design works and can be used. Lastly, the test shows that the proposed system architecture and instructions for scripting the tool can result in a well-operating tool. Finally, recommendations for future research are given.

In the design of steel structures, optimisation methods promise cheap, light and sustainable structures. However, the resulting designs tend to have a high diversity of profiles, making them unbuildable. Furthermore, the optimisation problem is mathematically complex, leading to a long and potentially unsolvable optimisation process. Grouping methods solve both issues by finding the optimum solution, for which the number of distinct profiles is limited. Multiple grouping methods exist in literature, and it is not known which is the best: the methods have not been applied on the same problems, and the computational effort has not been compared. This gap in literature leads to the following question: “Which method for grouping can find the lightest and cheapest steel structure with minimal computational effort?” To answer this question, a comparison of the existing grouping methods is made on their theoretical and numerical performance. The theoretical comparison comprises the size and properties of the search space, and the number of additional calculations. The numerical comparison consists of weight optimisation of eight benchmark problems. For each structure and method, the weight of the solution and corresponding computational effort is evaluated. Manually grouping of members, which is the most popular grouping method, relies on the engineer’s expertise and rules of thumb. This method requires no additional calculations but in general fails to find the optimum grouping for a light or cheap structure. Other existing methods include the geometry, axial force distribution or an ungrouped result in their grouping process, or adapt the optimisation problem. Of these methods, only the cardinality constraints method is guaranteed to potentially find the lightest grouped design, while reducing the search space for a small number of groups. However, it creates many local optima, which increases the complexity of the search space. In the aim of finding a grouping method which creates a simple and small search space and has low computational effort, the fully stressed combinatorial search method is proposed. In this method, the grouping is found by a combinatorial search, which evaluates the estimated weight or costs of a restricted set of groupings based on the weight per unit length of the members of a fully stressed design. Then, optimisation of a small and simple search space finds the corresponding optimum profiles. These steps are repeated, in which the fully stressed design uses the result of the previous optimisation as its reference design. The loop repeats until the grouping is unchanged, or the result diverges. In all numerical experiments, the new method gave results with a low weight, while it kept the computational effort to an acceptable level. It gave the lightest design for four out of eight problems and showed high certainty for converging to the lightest design in two problems. For the other two problems it performed second best. Conclusively, this method is the best available grouping method for steel structural optimisation. In case of cost optimisation, the new grouping method can efficiently find the optimum design including the optimum number of groups; the new method converges to cheaper design with less computations than in the case no grouping is applied. For a real-life case-study, the costs of a design were reduced with 7.3% compared to a manually grouped design and with 19.6% compared to the conventional design process. I suggest that further research focusses on further development of the new grouping method as proposed improvements can be made on the initial design, and the number of computations in the combinatorial search and fully stressed design. Moreover, the effectiveness of a suggested simplification of the new method should be investigated. This would allow application for engineers who are not able to apply a mathematical optimisation method. For practical application, incorporation of building codes and cost functions with a well-defined scope are desired. Finally, utilisation of the grouping methods in other applications is possible, but the performance of the methods should be evaluated per application.

Researches have been conducted to involve the sustainability of energy in the building's early design stage. The methods used include the IEF-based method, the BIM-API-based method, and other approaches. However, these methods have not helped architects out in the early design stage since the complexity of the assessment is not decreased. The contradiction of increasingly complex energy simulations and early conceptual designs forms a research gap in energy optimization. As changes in the early design stage have more effect on the buildings and make less cost, the introduction of on-the-fly energy assessment in the early stages is of great importance. This thesis developed a framework to help boost energy efficiency in building design. The framework aims to improve the efficiency of energy assessment by providing simultaneous and on-the-fly energy performance assessment of the design. BIM software Revit and the visual programming environment Grasshopper were integrated via Rhino.Inside, a bridge between the BIM environment and others to perform the assessment. The workflow of the framework contains three parts: data input from BIM models and the determination method NTA 8800, the connection by Rhino.Inside and the computation of the Grasshopper script, the final results, and the report produced by the Grasshopper script. A script in Grasshopper as a demonstration of the framework was developed as such that Revit models can be directly linked to the energy analysis, and the results can be returned simultaneously. The script was created based on a preliminary case study and two sets of studies were conducted to validate it. The case study of a tiny house was first investigated to test and validate the developed tool. The energy demand result of the developed tool has only a 3% difference for the case study calculated via Uniec 3, a verified software used in the Netherlands. The developed tool was also validated through 4 variants with different configurations to find out if the tool is accurate and robust enough concerning dimensions and physical properties. The comparison of the results shows that the developed tool can produce steadily accurate results that vary within 5% from the standard outcome. In addition, the study indicates the framework's potential of optimizing the building's performance on energy efficiency as the proposed framework significantly shortens the time and workload compared to Uniec 3 which requires a body of manual input. The study in this thesis integrates the BIM models and energy analysis to enhance the sustainability concept in the building design industry. It fills the gap in the application of semi-automated BIM to the BEM framework in the early design stage of buildings. The developed framework provides a useful tool and practical benefits to the field of energy efficiency. This study investigated the potential of applying on-the-fly energy assessment in early design stage, which could be developed further in future work to explore more or better solutions.