Dynamic responses and damage mode of reinforced concrete slabs under confined blasting loads induced by thermobaric explosive: Experimental and numerical investigation

Abstract

This study is based on the finite element method (FEM) considering the Miller model to investigate the blast loading of thermobaric explosives (TBX) in confined spaces and the dynamic response and damage modes of reinforced concrete (RC) slabs. The Miller model considers the secondary reaction of the explosive blast products. It can effectively describe the violent afterburning effect of TBX. In the confined space, wall reflections and Mach reflections of the blast shock wave form a pressure response with long duration and multi-peak oscillations, which creates an approximately uniform load impulse on the surface of the RC slab. The peak pressure of the blast shock wave induces collapse damage, while the uniform load impulse induces bending deformation of the slab. The bending deformed RC slabs showed a large residual displacement, which increased linearly with the increase of the average impulse distributed over the surface of the RC slabs.