Numerical Simulation for the Effect of Ground Stress on Explosive Fracturing

In order to reveal the influence of ground stress on the fracture and propagation during explosive fracturing,the lab experiment of explosive fracturing was carried out,and the fracturing numerical model established based on elastic-plastic-damage theory.By means of the testing result and its accuracy verification of the numerical model,the influence of ground stress on fracture and distribution in explosive fracturing was studied.The study results show that the explosive did not crush the surrounding rock of the borehole,and cracks created and extended in curved forms;the primary long and wide cracks and secondary short and narrow cracks are formed by explosive fracturing in surrounding rocks of borehole,the propagation of primary cracks,which are perpendicular to the minimum horizontal in-situ stress direction,is controlled by ground stress;the length and quantity of cracks also vary with different ground stress.Consequently,learning about the magnitude and direction of the ground stress is helpful for the control of propagation and distribution of the primary cracks in explosive fracturing.