Study On Technology Of Goaf Management And Recovery Of Residual Ore In Guyi Mining Area Of Fozi Mine

After years of short-hole shrinkage mining, a lot of goaf been left behind in upperof104ore body in Fozi Mine. Due to the disorder treatment in the early, not only itcaused a great deal of the pillar in the empty area resources, but also it formed acomplex Situation of goaf, this Poses a serious threat to the lower ore body’s mining. Inthis paper, the No.104ore body goaf group as the research object, the main researchcontents and conclusions are as follows:(1) Through the field investigation and indoor mechanics experiments, we got goafdistribution, occurrence characteristics, and the structural elements and the physical andmechanical parameters of rock mass. Then classify stability of surrounding rock byusing set pair analysis model to evaluate its stability.(2) Analyze the goaf surrounding rock and the supporting pillar stability by usingthe method of strength reduction theory formula method. The results show that, thesurrounding rock in the goaf exposed did not reach the limit of size of area, its stabilityis good. The majority of the pillar in goaf have a higher safety factor, but the supportpillar of100m in large thickness body is at low safety factor, it need to take measures assoon as possible.(3) Combined with the goaf stability conditions and occurrence characteristics ofresidual pillars, put forward "all collapse","full backfill" and "combined with collapseand backfill"3kinds of feasible goaf treatment and pillar stoping scheme. And10maineffects were evaluated by the fuzzy optimization method, finally determined thecombined with collapse and backfill is the best method.(4) Using FLAC3Dnumerical simulation calculation of the optimum scheme ofsimulation software, analysis of goaf treatment in different stages of mining area and thevariation of surface stability of surrounding rock stability. The results show that theselected scheme makes stress concentration zone of surrounding rock fully mobile and collapse, and makes goaf in the underpart filled. It achieves pressure relief and rockmovement controlling by caving pillar and roof caving. This scheme can effectivelyeliminate the hidden trouble of goaf and recovery of residual pillars security.Through the scheme proposed by the above research, provide a theoretical basisand technical guidance for goaf treatment and recovery of residual ore problem in Guyimining area. At the same time, it also has some reference for other similar problems inmine.