Measures of Structural Robustness — Requirements and Applications

The investigation of structures concerning their susceptibility to progressive disproportionate collapse is attracting increasing attention. At present, there is neither a uniform theory of progressive collapse and collapse resistance nor any agreement on terms and nomenclature. Codes and other relevant literature require a reduction in the susceptibility to progressive collapse. However, mainly qualitative and hardly any quantitative recommendations are provided. Collapse resistance can be influenced in various ways. One possibility is through the structural robustness. In a robust structure, no damage disproportionate to the initial failure will occur. To examine a structure in terms of its robustness, a quantitative description of the robustness by means of a measure would be useful. In this work, basics for the development of measures to quantify structural robustness are formulated. Essential definitions are suggested and the requirements for measures of robustness as well as possible applications are discussed. A selection of publications on the quantification of robustness, or related characteristics such as vulnerability, are presented and discussed regarding the proposed requirements and applications.