Dynamic Response of the Steel Plate Under the Impact of High-Speed Coal Projectile

Abstract

The coal-rock projectiles induced by gas explosions in coal mines have a strong destructive effect on mine facilities and equipment, which are mostly made of steel. The LS-DYNA is used to simulate the process of coal projectile striking the steel plate. The results show that during the failure process, the morphological change of the projectile consists of three stages including plastic deformation, partial crushing, and complete crushing, and the steel plate pits at the impact point. The duration of the stress peak value of the steel plate increases as the impact velocity increases. The farther away from the center point, the smaller the stress peak value is, and the shorter the duration is. When the impact velocity is 100 m/s and 300 m/s, the axial velocity curve at the impact point of the projectile is pulsating. When the impact velocity reaches 500 m/s, the axial velocity of the projectile rapidly increases and then tends to be stable. As the impact velocity increases, the energy absorbed by the steel plate increases, and the rate of increase also increases. However, the proportion between the absorbed energy of the steel plate and the initial kinetic energy of the projectile decreases. The projectile conversion energy of the 1 mm steel plate is slightly larger than that of 1.5 mm and 2 mm steel plates, and the energy absorbed by the steel plate decreases with the increase in thickness of the steel plate. When the thickness of the steel plate is more than 2 mm, the thickness of the steel plate has little effect. The results of the study have a direct sense for the antiknock design of coal mine facilities and equipment.