Rock-like brittle material fragmentation under coupled static stress and spherical charge explosion

Theoretical analysis and laboratory tests were performed to investigate the fragmentation of rock-like materials under coupled static stress and spherical charge explosion. The variations of the explosion crater shape and volume were studied. The experimental results indicate that uniaxial static stress changes the shape of the explosion crater at the free surface from circular to elliptical and increases the volume of the explosion crater. In addition, a higher material strength corresponds to a smaller explosion crater volume. Under biaxial equal stress condition, the failure zone on the free surface is always circular and the volume of the explosion crater decreases and subsequently increases. The influence mechanisms of static stress on the explosion crater are discussed in detail, and the experimental phenomena are well explained.