Application of polyurethane foam decoupling charge structure in smooth blasting
Aiming at the phenomenon of large over-excavation and low half hole rate during coupling charge smooth blasting of ANFO with low detonation velocity in an underground mine,a flexible material of polyurethane foam is adopted to realize radial decoupling charge,so as to reduce the quantity of single-hole explosives,and,to reduce the damage to the retained surrounding rock caused by explosion impact.Through the simulation calculation of decoupling charge blasting with polyurethane foam materials,it is found that the crushing circle and the compressive stress of the retained rock mass are significantly reduced after blasting.In order to reduce the explosive cracks in the direction of the retained rock mass and to increase the proportion of explosive energy used to break the rock,slits are opened on the polyurethane foam ring.And the simulation calculation results show that double-hole slits shows favorable formation effect,additional,remaining blast cracks are significantly reduced.According to the simulation results,a field smooth blasting experiment with polyurethane slitted radially is conducted.After blasting,the technical indexes of the blasting,such as half hole rate and over-under excavation volumes of the retained rock mass are significantly improved,compared with the continuous charge structure of ANFO with low detonation velocity.Furthermore,it reduces the unit consumption of explosive and provides references for the process improvement of similar blasting.
万方数据
维普
