Applied Research on New Short-delay Blasting Technique in Large Section Rock Roadway of Coal mine
Xu Shaoming 1 Zong Qi 2 1 Engineering Corporation of Huaibei Mining Group, Huaibei Anhui, 235029 2 School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001
For the current coal mine permitted millisecond delay electric detonator delay time between each segment is 25 ms already cannot satisfy safety and efficiency excavation of large sections rock roadway, a new millisecond delay electric detonator was designed and ordered, and the field test was done. By increasing the delay time between cut-hole and auxiliary-hole, cut blasting efficiency was improved, casting distance of ganguet was reduced and blasting pile was concentrated, which was beneficial to the rock loading work. And by medium-deep hole blasting and whole section one-time blasting, the cycle operation time was saved. The expectation aim of improving the utilization rate of borehole and roadway shaping quality, reducing the material consumption and safe, quick and efficient construction was realized.