Robustness of engineering structures and its role in risk mitigation

Abstract

Robustness is an attribute that is required in most structures, especially major structures and lifeline engineering structures, to mitigate the risk of disproportionate failure in case of accidental damage. The present paper discusses structural robustness and its significance to risk mitigation, the focus is on robustness analysis and effective strategies to ensure robustness. Structural robustness is defined here from the viewpoint of energy – robust structures should be capable of absorbing energy input adequately, while keeping the resultant damage proportional to the original cause. This provides insights into structural performances under accidental damage. It is argued that structural robustness can be achieved by improving the energy absorption capacity of structures and mitigating the potential energy or work released during damage propagation. Typical means to improve robustness are enumerated and illustrated by case studies. Finally, the entire paper is summarised and research needs identified.

Keywords:

• structural robustness
• risk mitigation
• energy
• disproportionate failure

Acknowledgements

The first author thanks Professor Thomas Vogel of the Swiss Federal Institute of Technology Zurich for assistance with the references. The constructive comments made by the reviewers are also gratefully acknowledged.