Dynamic Responses of an Underground Opening Subject to Impact Loadings in Blocky Rock

The stability of rock blocks near the underground opening may be influenced by the impact loadings caused by either natural hazards or man-made disasters. This paper addressed the dynamic response of the rock blocks under impact loadings. The experimental tests were carried out to record the movement as a function of vibrations using the impact-induced rock burst system. Granite blocks were placed in the steel frame and loaded to the designed quasi-static condition at first. Permanent jumps of displacements toward the opening were observed after the pulse loading was applied. Analytical investigations were carried out to understand the macroscopic friction during the vibration progress. The results showed that the friction force was reduced by 4