Numerical study on the dynamic response of coal mine seals under methane explosion loads

Abstract

Seals play an important role in regulating air flow and preventing disasters in coal mines, so it is essential to ensure their effectiveness. However, the generation of large amounts of explosive methane and the enclosed space in mines lead to impact strength that far exceeds the explosion pressure in open space, causing damage to seals. Therefore, it is necessary to study the dynamic response of seals under explosion loads. In this paper, the blast resistance of seals constructed of concrete material is analyzed by LS-DYNA under four explosion overpressure history curves, which correspond to normal overpressure, moderately high overpressure, high overpressure, and worst-case scenarios of coal mine gas explosion. The stresses and displacement distribution of the seal are obtained, as well as the damage pattern under the impact action. In addition, the effects of interlayer material, reinforcement, arch structure seal, constraint conditions and seal thickness on the blast resistance performance are analyzed. The results show that adding constraints and thickening the seal are the most convenient measures to strengthen seals. The optimal formula is selected by comparing five thickness calculation formulas with the results of this paper.