Use of probabilistic methods in evaluating blast performance of structures

Abstract

The social and political climate of the modern world has lead to increased concern over the ability of engineered structures to resist blast events which may be incurred during terrorist attacks. While blast resistance design has been prominent for years in the industrial and military setting, it is starting to gain importance for structures which have been traditionally designed for aesthetics and which have high occupancy density. In these situations it is important that not only materials but the geometry of the building be optimized to reduce the effects of such an attack. However, designing a structure only for prescribed code requirements does not necessarily give a prediction of the post-blast behavior of the structure. Similar to the use of performance-based engineering for seismic events, the effects on a structure designed for blast loading should not be speculative but rather should exhibit expected behavior which is appropriate for the parameters of the given blast. Accounting for uncertainty of a potential blast event by assessing the structure in a probabilistic approach may lead to a more prudent and predictable assessment of damage and loss for the owner. The work herein attempts to provide an overview of the precedent of use of probabilistic methods in structural engineering, the current state of practice in blast engineering and set forth a framework and example by which probabilistic methods may be extended to blast considerations.