Blast Design-Basis Threat Uncertainty and Its Effects on Probabilistic Risk Assessment

Abstract

AbstractAt present, the deterministic approach to blast-resistant design appears to be the prevalent philosophy in practice, as suggested by the notion of design-basis threat (DBT) outlined by the ASCE/SEI 59-11. In this study, it is argued that even in the case of a clearly defined blast scenario, the resulting loading parameters can show a remarkably high degree of uncertainty, as corroborated by data from arena tests. Therefore, future standards should integrate a DBT definition guided by probabilistic risk assessment (PRA), in order to extend the general principles of limit state design philosophy to blast-resistant design. This paper investigates the sources of the variability observed in key blast wavefront metrics, including the peak pressure, specific impulse, positive phase duration, and decay coefficient. This objective is accomplished by quantifying and propagating the uncertainty associated with several input parameters, such as the mass of explosive, equivalent TNT–mass factor, pressure trans...