(1. State Key Laboratory for Coal Mine Disaster Dynamics and Control，Chongqing University，Chongqing 400044，China；
2. National and Local Joint Engineering Laboratory of Gas Drainage in Complex Coal Seam，Chongqing University，
Chongqing 400044，China)
Abstract：The water hammer pressure and stagnation pressure during the impacting process of water-jets were analyzed based on the theories of hydrodynamics and elasticity. Radial distribution functions for the dynamic pressure in the cross-sections of water-jets during different pressure stages were derived. Numerical models for the transverse isotropic rocks under water jet impacting at different angles were developed and the influence of impact angle on the breaking of rocks was studied assuming ? = 0°，45°，90°. A number of impacting experiments on the transverse isotropic sand-stones were conducted at different impacting angles. The numerical analysis and the experiments reveal that the water hammer pressure produced broken pits on the transverse isotropic rocks and the stagnation pressure caused the initiation and development of cracks inside the rocks. The transverse cracks，inclined cracks and splitting cracks appeared accordingly when the water-jets impacting were perpendicular，inclined and parallel to the beddings of the transverse isotropic rocks.
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2014, Vol. 33 
