Research on the Safety of Water Hazard During Working Faces Mining Near Coal Seam Hidden Outcrops
The working face mining in the shallow coal seam hidden outcrop area of Zhangji Coal Mine is threatened by the overlying loose aquifer.The original design of the 1306 working face used layered mining,which makes it difficult to improve the production and efficiency of the working face.Through FLAC3D numerical simulation and analysis of the overlying rock failure law of fully mechanized caving or large mining height fully mechanized mining under similar geological conditions,a relatively large collapse mining ratio and crack mining ratio are selected to predict the height of the"two zones",and compared with the empirical formula for predicting the height of the"two zones"in fully mechanized caving mining,the"minimum safe thickness"method is used to select the thickness of the protective layer,and the height and mining thickness of the sand control safety coal rock pillar are determined.The results show that the minimum bedrock thickness in the mining area of the 1306 working face is greater than the minimum sand control coal rock pillar thickness required for full thickness fully mechanized caving mining.The working face can adopt full thickness fully mechanized caving mining until the end of the design stop mining line,which is conducive to achieving high-yield,efficient,and safe mining in the mine.
hidden outcropnumerical simulationcoal rock pillar heightsafe mining
国家科技期刊平台
NSTL
万方数据
