Study And Application Of The Law Of Strip Mining In Kilometer Deep Mine

At present,there are few research achievements on strip mining in kilometer deep well.This paper selects ZhangXiao Lou mine mining area of PangZhuang Coal Mine as research object,analyzed the law of surface movement and deformation in kilometer deep mining based on the measured data in the mining area.Combined with theoretical analysis and numerical simulation methods,we researched the law of surface movement and deformation of strip mining under the condition of kilometer depth and draw the following conclusions:(1)Through collated,analyzed east-west and north-south surface movement observation data of Xuzhou PangZhuang Coal Mine of ZhangXiao Lou mine mining area,master the law of surface movement and deformation of it.According to the surface subsidence basin curve of the east-west observation line,we can know that the subsidence basin in the direction of the direction is fully mining.Obtain the relative probability integral parameter of the area by the measured data,provides reference and basis for the selection of the parameters of deep mining or deep strip mining in other mining areas or in the similar mining conditions.(2)Based on the theoretical analysis of the main factors that affect the surface subsidence of the strip mining in kilometer deep mine,we concluded that the selection of coal pillar's width mining and leaving width are the main factors.And with the related theory,the mining pillar's width is 0.0246?mH/(1-?)?b?1/8H,leaving pillar's width is a?0.0246 mH.(3)Based on measured data and mining geological conditions of Zhangxiaolou mine as the prototype,with the help of FLAC3 D software,the main influence on the surface movement and deformation of deep strip mining—such as mining depth,mining thickness,mining width and recovery ratio—is studied and obtain the curves of surface subsidence and horizontal movement under different effects.And draw the following conclusions:(1)Compared with the shallow strip mining,the condition of kilometer strip mining's maximum subsidence,tilt,curvature value are smaller and has gradually stable trend with the increase of mining depth.(2)In the design of mining width,the shallow strip mining method of 1/10 H ~ 1/4H is not suitable for deep mining,it should be designed between 0.0246?mH/(1-?)?b?1/8H according to the results of the simulation experiment.(3)Compared with shallow strip mining,kilometer deep coal strip mining more difficult to achieve full mining,and the subsidence coefficient is also small when achieve it.Therefore,we can improve the recovery rate to reduce the waste of resources when design with a deep mining in kilometer.(4)Combined the study of measured data and the actual mining situation,using FLAC3 D software,studied the impact of different coal seam spacing and strip space position on the overlying strata and surface movement and deformation under the condition of multi-coal seam strip mining.Through simulation analysis,the following conclusions are drawn:(1)In the multi-coal seam strip mining of kilometer deep,the maximum ground deformation raise with increase of stagger the degree of coal pillar and seam spacing.When the coal pillar is absolutely aligned up and down,the coal pillar is the most stable,and the value of surface movement is minimum.(2)The surface subsidence rate increases with the increase of coal spacing,and a large increase in the trend.(5)According to the results of theoretical analysis and surface movement law of ZhangXiao Lou mine kilometer deep mining,obtain the reasonable parameters of the strip mining probability integration method which can be used to design the coal mining under the LiuJi,and forecast and analysis to the design plan.Predicted results show that the maximum value of deformation is less than the standard of?building failure criterion.After coal mining,the building of surface will not produce obvious cracks and most can be used without repair,the design is feasible.