Definitions of robust structural geometries : metrics and form finding

Abstract

Robustness varies highly between applications and consequently it is difficult to precisely quantify. However, robustness is a property of a structural system and thus can be described as a function of its form; in other words, as a function of topology, geometry and member properties. This thesis investigates the relationship between both a structure's geometry and topology, and robustness. Two quantitative metrics are proposed to quantify a structure's robustness as a function of geometry. The first metric is a measure of a member's importance relative to others in the redundancy of a structural system. The second metric characterizes the robustness efficiency of the entire structure. These metrics are developed using a novel analysis method coupled with an interactive MATLAB script which infers properties of a redundant structure through the analysis of its stable substructures. Together, these metrics give designers a powerful tool to evaluate the robustness of their preliminary structural design based soled on geometry and static equilibrium. Moreover, using these metrics, geometry optimization techniques are then implemented to discover robust structural geometries for given topologies and the general parameters that describe them.