Study Of The Law And Prevention Measures Of Ground Surface Subsidence In Pillar Mining Near Earth's Surface

The ground surface subsidence caused by room and pillar mining near the earth's surface is a highly serious underground engineering problem. The balance of original rock stress is destroyed, then ground surface is metamorphosed and displaced, and even have large acreage movement in the course of underground mining. The paper summarizes the research present condition, the development trend and the existing problems of the ground surface subsidence. Aim at the practical characteristics of room and pillar mining near the earth's surface, the law and prevention measures of ground surface subsidence of room and pillar mining near the earth's surface are researched based on practical case of Shaodong gypsum Mine. The main contents and conclusions are as follows:(1) The stability analysis of ore pillar and overlain strata is carried out,and the regulation of the ground surface subsidence is evaluated qualitatively.The result of reserch shows that sudden ground surface subsidence caused by unstability of ore pillar and overlain strata will not come up.(2)The computing method based on probability integration method is improved on the basis of others'research.The improved computing method has several advantages,such as less calculation, strong pertinence,high velocity, high efficiency and etc.(3) Using VB and MATLAB program, the forecasting system for ground surface subsidence is builded based on the The improved computing method.This system can achieve data acquisition, calculation of subsidence, data processing, visualization,data output and etc.The deformation regulation of Shaodong gypsum Mine reflected by settlement, Inclination, curvature, basin, isoline, fitted equation and etc can be obtained based on the forecasting system.(4)The FLAC3D is used to simulate the the ground surface subsidence of Shaodong gypsum Mine.The ground surface subsidence caused by room and pillar mining near the earth's surface is researched in two aspects of mining sequence and lithological change taking the forecasting system as research platform.And the contrast and analysis are carried out between the two computing method, probability integration method and numerical method.(5) The evaluating principle and evaluating method of the ground surface subsidence caused by room and pillar mining near the earth's surface are formulated based on the research conclusions of this paper and correlative standard.And the treatment processes are suggested in two aspects of prevention and governance.