Research on Roof Cutting and Pressure Releasing Technology of Directional Fracture Blasting in Dynamic Pressure Roadway

Affected by mining activities, 3 −1 103 tailgate of Hongqinghe coal mine is seriously deformed. The floor of tailgate cracking and tilting, and two ribs appearing in the net bag, which affects normal transportation and pedestrians. To solve this difficulty, this paper study on the technology of directional fracturing blasting for pressure relief of dynamic pressure roadway. First of all, taking method of theoretical analysis, the mechanical mechanism of directional blasting and the relevant calculation formula are expounded. Afterwards, the mechanical model of roof cutting of roadway is established. In order to analyze the evolution and propagation of effective stress, directional blasting model is established by using LS-DYNA numerical calculation software. In the next part, the roof control technology of directional cut blasting is put forward. In the end, the blasting effect is observed, and the deformation of the roadway before and after pressure relief is monitored and analyzed. The results shows that directional fracture blasting have obvious effect of joint formation, and the effect of pressure relief is remarkable, effectively controlling the deformation of surrounding rock under dynamic pressure.