Investigation on rock breakage by high-velocity water jet impact under different stress loading conditions: Fracture characteristic, stress and damage evolution laws

Abstract

Numerical simulations were conducted based on SPH-FEM coupling method to investigate the damage evolutions and failure mechanism of rock impacted by a high-velocity water jet under different stress loading conditions. The influences of stress loading magnitudes and stress differences on the rock fracture characteristics, including parameters of broken pit morphology and crack propagation, were obtained. The development of damage and crack inner rock will be inhibited due to stress loadings. The rock failure mechanism in different breakage zones were revealed by exploring the damage and stress evolutions inner rock. The results show that the rock surface elements near jet impact center suffers from the instantaneous brittle failure, which is scarcely affected by stress loadings. The elements inner rock below jet impact and sidewall elements surrounding broken pit are destroyed due to the cumulative plastic damage, and the stress loadings delay the initial damage time and prolong the cumulative damage time.