Citation

Zhou XQ, Hao H. Int. J. Impact Eng. 2008; 35(5): 363-375.

Copyright

(Copyright © 2008, Elsevier Publishing)

DOI

10.1016/j.ijimpeng.2007.03.003

PMID

unavailable

Abstract

Accidental or intentional explosion events often damage structures and injure occupants. Terrorist bombings that have occurred in the past few years have greatly heightened the awareness of structural engineers of the threat of terrorist attack using explosive devices. Blast loading has received considerable attention in recent years. Much research has been done to estimate the blast loading and analyse blast effects on structures. Protecting civilian buildings from the threat of terrorist activities has also become one of the most critical challenges for researchers today. Some critical infrastructures, such as embassies, government buildings and power plants, need be carefully designed or retrofitted to resist blast loading and protect occupants because they might be potential terrorist targets. One simple way of enhancing the survivability of these structures to blast loads is to provide a blast barrier, or blast wall, at the perimeter. A blast wall provides a stand-off distance to protect the structure from an external explosion. Moreover, it acts as an obstacle in the direction of the blast wave propagation. Therefore, some portion of the explosive energy is reflected back, and then the distribution of the blast pressure on the structure behind the barrier is changed and the peak pressure is reduced.

Experimental results and numerical simulations have demonstrated that a protective barrier can effectively reduce blast load and, therefore, protect structures from an external explosion. However, there are no formulae in the open literature that can be used to estimate the blast loads on a structure behind a barrier. In this paper, pseudo-analytical formulae based on numerical results are derived to estimate the reflected pressure-time history on a rigid wall behind a protective barrier. Numerical simulations of blast wave propagation are carried out to estimate the peak reflected pressure and the impulse on a rigid wall behind a blast barrier. The shock wave front arrival time and positive phase duration are extracted from the numerical results. Pseudo-analytical formulae, which are derived from the best-fitted curves of the numerical results, are suggested. These formulae can be used with those given in TM5-1300 or other methods for blast pressure estimation in the no-barrier case, to estimate pressure-time histories at various building locations behind a protective barrier.