Technical Study And Application On Middle Deep Hole Smooth Blasting For Hard Rock Tunnel

This article study the middle deep hole smooth blasting destruction of tunneling in hard crag by theoretical analysis -simulation in laboratory--commercial testing in status quo.Fist, analyzing mechanical features of the blasting explosive detonation and principle of cutting blasting and smooth blasting adopting theory of explosive detonation and explosive stress wave in rock. The depth of borehole, the number of borehole in workshop, form of undermining and factors of cutting blasting, factors of breaking blasting, factors of smooth blasting(including distance between borehole, density of borehole and thickness of smooth blasting layer),construction of charge, subsequence of detonation and time of delay have been thoroughly discussed. And putting forward theoretical methods for determining of factors of the middle deep hole smooth blasting in crag.Further studies on blasting factors, including smallest resistance wire of breaking blasting, density of borehole of breaking blasting and smooth blasting has been carried out though experimental explosion on coupons consist of sand-cement grout with small quantity of explosion.Commercial test has been proceeded in status quo with the blasting factors and scheme for middle hole smooth blasting that have been defined based on theoretical analysis and laboratory simulation and actual situation of tunneling in lane construction of two levels cart yard for riding the humanin Daihe coal mine in Huaibei mining industry group. Good results has been got. The percentage of blasting reached 90% and upward, the formation of the lane is well, the speed of tunneling is faster than ever, the safety of execution is promoted the evaluation is more suitable to the practice in status quo .based on fuzzy mathematics that can synthetically and systematically consider multi-ingredients.According to the theoretical results of factors of the middle deep hole smooth blasting in hard crag ,the achievements of this thesis can be a good reference for execution of the middle deep hole smooth blasting in hard crag.