Abstract:

In order to study the damage characteristics of gas explosion from double explosion sources in roadway wall, the gas explosion model of roadway with double explosion sources was established by using LS-Dyna, and the pressure propagation and impact stress of shock wave in roadway under the gas explosion action of double explosion sources were analyzed. The change of axial pressure in the roadway and the damage to surrounding rock in the symmetrical section were measured when gas explosion with double explosion sources occurred. The research results show that the interaction between the shock waves generated by double explosion sources in the roadway results in a significant disparity in pressure compared to that of a single explosion source. At each axial position where the gas explosions from the double sources occur, there are two distinct pressure peaks, with the magnitude of the first peak negatively correlated with its proximity to the nearest explosion source. The value of the second peak pressure is negatively correlated with its distance from the collision surface where shock waves from two sources meet. The peak pressures before and after this collision were not a simply linear superimposition, but a sharp rise. The damage evolution process on surrounding rock wall surfaces resembles that of diffusion for shock wave pressure propagation and shock stress, although it is lagging these two phenomena. Furthermore, the duration of shock wave action plays a crucial role in determining the thickness of damage inflicted on surrounding rock formations, with roof damage being most severe in roadways subjected to double explosion source gas explosions.

Key words: double explosion sources, gas explosion, roadway, shock wave, impact stress, damage characteristics