Crushing Removal Conditions and Experimental Research on Abrasive Water Jets Impacting Rock

This paper describes the complex process of rock crushing removal by AWJ impact from the microscopic perspective. The acceleration and deceleration mechanism of abrasive particles throughout the whole process of single abrasive particles impacting rocks, the spherical cavity expansion mechanism of the abrasive particles’ impact on the rock, and the elastic contact force of the collision between the abrasive particles and rock were investigated; a mathematical model of AWJ’s impact on the rock crushing removal conditions was established; and the threshold values of the jet impact parameters were obtained. The mathematical model of the rock crushing removal conditions was verified through numerical simulation and jet impact experiments. The research results show that the theoretical value of the jet impact velocity that meets the conditions for limestone crushing removal is greater than or equal to 36 m/s, and the theoretical value of the pressure is greater than or equal to 2.7 MPa. Numerical simulation was used to obtain the displacement of marked points, stress, and strain variation in marked elements of rock under different impact velocities. The effect of impact rock breaking obtained through the experiment demonstrates the correspondence between the test pressure and the theoretical pressure, which verifies the accuracy of the mathematical model of the rock crushing removal conditions.