Digital Workflow in Conceptual Structural Design - Parametric Design of Connections for Timber Gridshell Structures

Abstract

The question for discussion is how digital workflow, based on a parametric model, can be used as a method of design to increase the efficiency of spatial structure design. The study focus on the development of connections in timber gridshells. With a flexible digital workflow, the user is able to automatically generate structurally valid gridshell connections according to the gridshell properties. Such a workflow is supposed to enable more efficient communication between architects and engineers during the design process, by enabling the optimization of the economic, structural and conceptual sides of a project.

The digital workflow was implemented in a case study to engineer a spatial cabin structure in Norway and tested for different grid patterns and cross-sections. The case study involved cross-disciplinary work between two teams of engineers and one architect, increasing the realism of the research project.

The research lead to a digital workflow based around a particular proposed gridshell connection design. A parametric model with scripted structural verification algorithms was developed, and certain components were verified with a Finite Element Analysis. The structural verification mimics the intuitive engineering approach of testing different configurations, from simple to complex, until a valid configuration is found. The gridshell connection design proposed in the thesis also shows how the timber failure modes are critical in traditional slotted plate connection types.

The study finds clear advantageous with a digital workflow, e.g., better communication between architects and engineers and better predictions regarding structural stability. An on-hand parametric visualization of the structure facilitates for better understanding and communication, easier troubleshooting and less redundant work. It also makes it easier to experiment with changes and communicate options across disciplines, due to a work culture built on common terms.