The Analysis Of Roadway Safety When Thick Orebody Is In Layered Upward Mining

There is disturbance and destruction in surrounding rock stress when each layered mining is in progress and there will be a new stress field formed.The complex and overlying variety of stress field impacts seriously the safety of underground roadway and has been one of the key technologies that need to be solved urgently because of the restrictive to safety production in underground mining.This article takes iron ore in Macheng of Shougang for instance and discusses two mining areas stratified upward mining at the same time on the basis of numerical simulation.The article analyses the variety of stress field in surrounding rock with disturbing repeatedly,the distribution characteristics of superposed stress field and the safety of roadway surrounding mining area.The paper has the instruction function to stratified upward mining in deep underground.The main contents are as follows:(1)A numerical simulation study about two mining areas stratified upward mining at the same time in iron ore was carried out basing mining design.And this article analysis the regular pattern of stress field in dynamic mining process.This article gets safe,dangerous and destructive areas through security influence and provides basement for safety protection and mining scheme design.(2)According to the result of dividing the hazardous areas,Optimum design of reinforcement scheme is carried out.Then numerical simulation is carried on again and relays roadway lines which are in unsatisfactory hazardous areas to guarantee the safety of underground transportation.(3)This article establishes a safety evaluation system of underground mines based on Game theory and Cloud Model,which analyses comprehensively the safety of tunnel from 12 elements.Meanwhile,this essay sets up security levels for tunnel,which is conducive to get relatively rigorous,and gains satisfactory results.