关键词: 矿山滑坡危岩体, 定向抛掷爆破, 应急爆破排险, 离散元颗粒流软件, 数值模拟

Abstract: Mine landslide-hazardous rock mass is prone to secondary landslide disasters under extreme conditions.How to realize emergency risk elimination and the safety and effectiveness verification of risk elimination methods has always been a practical problem that plagues mining enterprises.Taking the landslide dangerous rock mass on the west side of Mohuandang as the research object,according to the technical idea of directional demolition and blasting of urban high-rise buildings,a directional demolition throwing blasting emergency elimination method is proposed.Using the method of bottom-up and inward-by-hole millisecond differential blasting,the landslide dangerous rock mass is directionally thrown to the designated position,in so as to achieve the purpose of emergency risk management and convenient procurement and transportation.Considering the irreversibility of the on-site risk elimination test,using the discrete element method,a dynamic analysis model for blasting dangerous rock mass in equal proportion mines was established,the blasting effect is simulated by the explosion point particle expansion method,set the no-reflection boundary,and analyze the final blasting hazard elimination effect,so as to verify the reliability of the method in advance.The results show that with a detonation time difference of 50 ms,when detonating sequentially from the 740 m—760 m—780 m platform and from the slope inward,the boulder yield is small,and there is no tight bottom,all landslide dangerous rock mass can be removed.The farthest throwing distance of the dangerous rock mass is 186 m,in line with the Blasting Safety Regulations (GB 6722—2014) of the flying stone safety distance regulations.The maximum blasting height is 22 m,mainly stacked on the 685 m platform at the foot of the slope,it can realize the safe and rapid mining,loading and transportation of dangerous rock mass.The research results provide a new method for the safe and rapid management of this kind of "shaky" landslide dangerous rock mass.It has certain engineering application value.

Key words: mine landslide dangerous rock mass,directional throwing blasting,emergency blasting and hazard removal,discrete element particle flow software,numerical simulation