Damage Mechanism and Wave Attenuation Induced by Blasting in Jointed Rock

This work uses a combination of simulations performed via numerical models and field observations studied the attenuation of deep-hole blasting stress waves and the evolution mechanism of cracks in a jointed rock mass. First, we conclude that the larger the joint angle is, the larger is the transmission coefficient and smaller is the fractal dimension. Second, the time difference between the peak stress difference and the maximum principal stress on both sides of the blasting hole in the horizontal direction of the rock mass with joints is relatively large, but there is no significant difference in the vertical direction. Finally, an unjointed-rock-mass model and multiple parallel joint model are established to explore the attenuation of stress waves and damage effect of multiple joint rock mass, it is concluded that the larger the angle, the smaller is the particle peak velocity and amplitude attenuation, and as the number of stress waves passing through the joints increases, the amplitude gradually decreases and the high-frequency amplitude decreases more significantly than the low-frequency amplitude. The research conclusions of this paper further reveal the damage mechanism induced by a blasting stress wave on jointed rock masses and the law of stress wave propagation and attenuation.

Automated summary

This work combines numerical models and field observations to study the attenuation of stress waves and crack evolution mechanism in jointed rock masses caused by deep-hole blasting. The study finds that larger joint angles result in larger transmission coefficients and smaller fractal dimensions. Additionally, there is a significant time difference between the peak stress difference and maximum principal stress in the horizontal direction of jointed rock masses, while there is no notable difference in the vertical direction. Furthermore, simulations of an unjointed rock mass and multiple parallel joints reveal that larger joint angles lead to smaller particle peak velocities and amplitude attenuations. As the number of stress waves passing through the joints increases, the amplitudes gradually decrease, with high-frequency amplitudes decreasing more significantly than low-frequency amplitudes.