Damage Assessment of Roadway Wall Caused by Dynamic and Static Load Action of Gas Explosion

Abstract

In order to obtain the damage characteristics of a roadway wall caused by a gas explosion, the damage evaluation theory of a roadway wall under the dynamic and static loads of a gas explosion is analyzed in this paper. Meanwhile, an evaluation method (overpressure–impulse criterion) is selected to evaluate the damage of the roadway wall under the impact load of the gas explosion. A mathematical model and a physical analysis model of the roadway wall damage are established by LS-DYNA software. The dynamic response of the roadway wall caused by the dynamic and static loads of the gas explosion is numerically simulated. The overpressure and impulse of gas explosion propagation are measured, while the damage data of the roadway wall under different overpressure and impulse loads are obtained. The P-I curves of the roadway wall under different dynamic and static loads of gas explosion are drawn. The fitting formula of P-I curves of the roadway wall is obtained. The influence of different geostress loads (0–20 MPa) on the P-I curve is analyzed. The shape of the P-I curve is similar under different geostress conditions. The difference is mainly shown in different sizes of P0 and I0. The numerical simulation results show that the P-I curve and the effect of geostress on roadway wall damage could reflect the dynamic response of the roadway wall. The damage degree and damage range of the roadway wall increase with the increase in explosion load energy. Under the action of different geostresses, the overpressure asymptote P0 and the impulse asymptote I0 show linear changes. The above research results could provide a theoretical basis and data support for the evaluation of roadway wall damage caused by gas explosions.