The Research Of Mining Environmental Geological Hazards And Countermeasures Of One Mining Area

Because of open-stope mining method, the ground collapse problem in No.1copper mining area in Chimashan have becomen increasing prominent, whichworsen by the illigal mining the tiberium spikes. Besides collapse, the accompanygeological problems as unstable rock, landslides arose. In order to eliminate theexisting hazards and prevent future disaster in mining area, the stablity analysisesof each disaster were carried out first, the comprehensive prevention measureswere put forward based on the stablity anlysis results:1) The forming mechanism of ground collapse is anlyzed from views ofmechnics, fellowed by discuss on its influencing factors. The specific backfillingand ecology restoring technology were taken and it need to set up the dam inentrance of collapse area to intercept people and animal. For the gound crackaround collapse pit, first clear the seam and then use the cement mortar backfillgrouting.2) For the unstable rock mass in mining area, the stablity was anlyzedaccording to limit euilibrium theory under natural state (no rainfall) and saturatedstate. The analysis results show insufficient security reserve for rock mass.Therefore, it use shallow hole blasting through remove the unstable rock mass.3) For slope locate in west-north of sunken pit, it adopt Geo-Studio to analyzethe stablity of slope in the state of natrual (no rainfall) and rainfall. The rainfallintensity and duration time are incoprated into consideration. The results show theslope failure after average rainfall for4days and heavy rainfall for1day. Ascountermeasures, the cutting top section and backfilling the toe shoud be taken andthen set up the retain wall at the toe of slope. Through anlysis of targeted slopestablity, it can be concluded that the designed slope has enough security reservesand the design sheme is reasonable.4) For the abandon slag in mining area, it is found unstable even under natural state through software simulating. Firstly, it can be recyclied to backfill the sunkenpit and set up intercepting dam. Spare slag stack must be cut slope to smaller slopeangle, and the surface can abopt clay hardening technology and vegetationmanagement;5)It can be found that rainfall infilatrating seriously deteriorated the stablity ofcollapse pit, slag heap, dam and slope. Measures shoud be taken to prevent waterinfiltrating. The gravel blind ditch accompany with precast tube drainage system isadopt to in backfilling area own to its strong resistance to deformation. For slopeand slag heap, it can set up drainage system at toe and platform. as measures ofecological restorating, the grass and tress planting plan shoud be taken afterbackfilling or slope cutting engineering.In conclusion, the paper anlyze the stablity of main geological hazards in No.1copper mining area in Chimashan and put forward the comprehensive preventionmeasure, which enriches the content of mine disaster sicence and meamtime ownpromotional, demonstrational and reference meaning to the other similar analysisof metal mining geological hazards.