Study On The Mining Pressure Rule Of The Working Face And Slope Stability Under The Side Slope Underground Mining

The open-pit mining will inevitably leave a large amount of unrecoverable end caving coal.The movement law of overburden in the working face of the overburden caving coal well is different from traditional mining.In this paper,theoretical analysis,numerical simulation and other methods and means are used to carry out a systematic study on the overburden movement structure and morphology,ore pressure law and the stability of the slope body at the working face of the coal mine with overlying caving face,and the following research results are obtained:(1)Winkler mechanical model of elastic foundation beam for overburden deformation and movement analysis in working face caving coal well is established.The deformation and fracture rules of overburden roof are analyzed,and the estimation methods of initial and periodic fracture distances of roof are given.The results show :(1)the first break distance,periodic break distance will be shortened with the increase of coal seam thickness,and with the increase of elastic modulus of the roof increase;(2)the roof of the periodic break distance will decrease with the increase in the number of broken cycle.(2)A numerical model for stability analysis of overburden and slope in working face of overburden caving well is established,and the influence of working face advancing distance on overburden deformation and movement,slope displacement distribution and slope safety coefficient is analyzed,and the position of stopproduction line in working face caving well is determined.(3)The effects of slope inclination,soft interlayer depth,soft interlayer thickness and soft interlayer on slope stability are analyzed.The results show that with the increase of slope inclination,the increase of soft interlayer depth,the decrease of soft interlayer thickness and soft interlayer lithology,the horizontal displacement of the slope increases,the slope safety coefficient decreases,and the position and shape of the critical slip surface of the slope are affected.