Parameter and Performance: Integrated Computational Performance Assessment of Structural and Daylighting Efficiency in Perforated Concrete Shell Structures

Abstract

With the advancement of computational design tools paired with performance assessment technologies, taking an interdisciplinary design approach at the early stages of design is largely facilitated. The Master Builder whose role has been fragmented between multiple professionals of many disciplines is being recreated, this time by facilitating seamless collaboration among a plethora of minds and perspectives. In this mode of collaboration, studying disciplinary tradeoffs also becomes part of the design process. This calls for a new design approach with an understanding of other disciplines. A building needs to stand up and needs to be illuminated, thus the structural and daylighting disciplines are associated with the purpose of architectural design. Despite the interaction between the two, there is little research showing the overlaps. Understanding this integration helps designers better understand how making a decision affects other stakeholders. This dissertation is at the intersection of computational design, structural performance, and daylighting performance assessment. Shells are the ideal typology for investigating this interrelation as their form is related with force flow, while adding holes to the shell’s surface not only introduces daylight but also affects force flow thus structural performance. By employing a computational interdisciplinary design approach, and by choosing perforated concrete shell structures as the main structural typology, I ask: How can the designer identify the design parameters that are shared between the discipline of architecture and an engineering discipline? What are the design parameters that co-exist in the structural and daylighting design disciplines? How may these parameters be used by designers? How do the design parameters affect performance in structural and daylighting discipline? What is the tradeoff between performance in structural and daylighting design? How can the results of a specific design case be useful for application to other design cases that do not necessarily have the same boundary conditions?

This research demonstrates how daylighting performance can be affected in the design of shell structures, a typology that is mainly driven by its structural design criteria in the literature. Also important is its demonstration of how a continuous shell can be perforated to the point at which becomes a grid shell; therefore, continuous and grid shells are two ends of a spectrum rather than two distinct structural typologies. A high-level significance of this dissertation is its marriage of the structural and daylighting disciplines and demonstration of how the two are closely related in shells by the perforation ratio. I find that perforation ratio is the most significant parameter that affects both disciplines and a number between 10% to 20% is the recommended limit for shell structures when translucent glazing is installed without any external or internal shading. One of the most significant contributions of this research is its methodological approach, which uses a formalized framework for categorizing design parameters in the structural and daylighting disciplines and then identifying overlapping design parameters. This design method, presented as a roadmap is the fundamental new component arising from this research. The final contribution of this dissertation explores how a generated solution space may become useful for other design projects which do not necessarily have the exact same boundary conditions. By abstracting the boundary conditions of new projects to match those in the solution space, the designer can examine possibilities and compare how making a decision in one field may affect performance in other fields.