Research On Rock Shift Observation And Subsidence Rule Of Surface Of Coal Mining Face

In this paper,based on basic research and analysis of surface subsidence rule of Anyang coal mine goaf,and prediction of the maximum ground subsidence,specific location of the maximum horizontal moving point,etc.,various kinds of related moving parameters of surface subsidence are obtained and the basic rules of surface movement deformation under this geological condition is revealed.Meanwhile,ground movement rule of the surface and rock movement parameters caused by mining are basis of research and settlement issues of"three-below" coal mining and environmental protection in mining area,are also key technologies to ensure the safety of surface building facilities.Through field observation combined with computer numerical simulation,comparative and analytic research of laboratory theoretical predictions and the field observation data,comprehensive use of data analysis,statistical analysis and other related technical methods and means,partial parameters of surface movement subsidence for the 1505 mining face are obtained:The boundary Angle of comprehensive mining ?0 = 74,?0 = ?0 =67°;synthetic angle of draw,Synthetic crack Angle ?" =80.2°;?" =?" =78.6° Angle of full subsidence?=58°;advance angle of influence?=65.7°;lag angle of maximum subsidence velocity=72.5°.The start interval of ground surface movement is 120m,the ground surface movement starting interval of Anyang 1505 minging face can be determined by 60%of the bedrock thickness or 30%of the average buried depth.Through the ground surface movement observation data and the destructive characteristics of surface subsidence,the mining subsidence rules under special conditions of deeply buried loess layers in Anyang coal mine are analyzed:it is characterized by permanent cracks on the outer surface of parallel goaf and closed crack failure of advance face as the mining face goes on;The surface movement is violent and movement period is short;The surface deformation near the ravine is serious;Because of the surface cracks in the loess,to some extent,the extent of surface deformation is inhibited and the surface movement Angle is increased.Be different from rules of surface movement under normal mining conditions,cracks of stepped form would be occurred in surface subsidence under conditions of mountain surface covered with thick loess,which would result in decreases of the boundary angle and increases of the movement angle.