Radial explosion strain and its fracture effect from confined explosion with charge of cyclonite

Abstract

Instrumented experiments were conducted in concrete models to study the explosion-induced radial strain and fracture effect of rock-like media under confined explosion with a charge of cyclonite. As a charge was exploded, two different radial strain waves were sequentially recorded by a strain gage at a distance of 80 mm from the center of charge. Through the attenuation formula of the maximum compressive strain(ɛ_max), the distribution of ɛ_max and its strain rate(ɛ) between the charge and gage were obtained. The effect of the two waves propagating outwards on the radial fracture of surrounding media was discussed. The results show that the two waves are pertinent to the loading of shock energy (E_s) and bubble energy (E_b) against concrete surrounding charge, respectively. The former wave lasts for much shorter time than the latter. The peak values of ɛ_rmax and ɛ of the former are higher than those of the latter, respectively.

Keywords

confined explosion loading / radial strain / radial fracture / concrete / shock energy / bubble energy

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