Explosion cratering and ground shock coupling effects in rock

• Revealed the laws of explosion crater volume in rocks and the attenuation of ground shock stress at various burial depths, and the compressed crater volume can characterize the magnitude of coupled ground shockt energy. • The equivalent closed explosion critical burial depth for Class III rocks is approximately 0.116 m/kg 1/3 . • Established a calculation method for the equivalent closed explosion yield in Class III rocks and proposed a functional expression for the equivalent yield coupling coefficient. This study explores the relationship between crater volume induced by explosions in rock and the coupled ground shock energy by conducting model tests and numerical simulations using explosive materials embedded in rock-like media at various burial depths. These experiments quantified crater dimensions and ground shock stress attenuation laws across burial depths. Results indicated a sharp increase in effective ground shock energy coupled into the rock as the scaled depth of burial (SDOB) increased. The volume of the compressed crater beneath the explosive center correlated closely with the effective ground shock energy. When SDOB approached the explosion cavity radius under closed explosive conditions, the coupled ground shock energy reached saturation. Based on compressed crater volume and peak ground shock stress, the equivalent critical burial depth for closed explosions in rock was identified. A calculation method for the equivalent yield coupling coefficient in rock was established, offering a theoretical basis for blast protection design in underground engineering under geological constraints.