Numerical and Experimental Analysis of the Effect of Rigid Barriers on Blast Wave Propagation

Many terrorist attacks have been carried out in recent years, such as in Oslo, Norway (2011), and more recently in Boston, Massachusetts, and in Volgograd, Russia (both 2013). Terrorist attacks target primarily public facilities, such as railway stations, government buildings, embassies, and the transport infrastructure. Research on the effect of blast loading on structures and interiors has gained considerable attention. Although there are many types of terrorist attacks, this paper focuses specifically on bomb attacks. Two different types of bomb attacks can be distinguished. In Oslo and Boston, the explosion occurred in an open space. In Volgograd, the explosion occurred inside a confined space. This paper primarily focuses on the type of bombing observed in Volgograd by presenting reduced-scale experiments on the effect of rigid barriers on blast wave propagation in the confined space of a railway station. The experimental data set was used for calibrating numerical finite-element models for use in predicting pressure-wave propagation. Very good agreement has been achieved between the experimental results and the numerical model results. The experimental results and also the numerical modeling results showed no significant effect of solid rectangular barriers in reducing the peak overpressure of the air shock wave in the area behind the barriers. Although the results indicate some effect on lowering the peak overpressure, this is limited to the area directly behind the barrier. At a greater distance, the effect diminishes rapidly and the pressure wave reverts to almost its original strength. In front of the barriers, the overpressure is increased, because the shock wave is reflected by the rigid barrier surface. The main benefit of such barriers would be that they absorb potentially harmful flying debris carried by the blast winds.