Dynamic analysis of a blast loaded steel structure

Abstract

With the increase in terrorist attacks in recent years, the effects of explosions on building become highly topical. In this regard, the paper deals with the analysis of blast loaded steel structures. When a blast loaded structure is analysed, as known, two major design issues and scientific challenges have to be approached and solved. The first issue derives from the analysis and description of the input dynamic load (time-pressure wave), being dependent on the type of explosion and explosive, while the second issue is related to the analysis of the actual dynamic response of the structure under impact. As such, real field blast tests using the so called ANFO explosives are first presented. The examined constructional system consists of steel rolled beams with two different type of cross sections (HEB100 and IPE120). The actual experimental observations are then assessed and compared with both SDOF and FE models carried out in ABAQUS. In doing so, the actual shape (i.e. decaying path for the pressure load) of the experimental blast wave is used, together with two further approximations for its description. The comparative calculations are then proposed for selected control points, in terms of mechanical and kinematic quantities (i.e. displacements, accelerations and strains). A critical discussion of the so collected comparative results is hence proposed.