Research On Surrounding Rock Deformation And Sectional Control Technology Of Roadway Crossing Through Passage

Chaili Coal Mine was built in 1964 and has a long production time.Some roadways were not fully considered for their long-term use in the future.Later,due to production needs,there was a phenomenon of cross-island mining,especially across the roadway.The research on the problem of cross-trackway mining is mostly concentrated on the mountain or the roadway parallel to the coal seam,regardless of the variation of the roadway and the overlying coal seam.For the cross-harvesting roadway,due to the change of the vertical distance with the overlying coal seam,the problems of different areas affected by mining,the deformation of the surrounding rock and the degree of damage are different during the mining process.Especially when the distance between some roadways and coal seams is small,the deformation damage caused by mining is more serious.These problems may cause the upper working face to deform greatly in the floorway during the propulsion process,and have a greater impact on the use of the subsequent roadway.Therefore,corresponding measures must be taken during the recovery of the working face to maintain the stability of the surrounding rock of the roadway and reduce the deformation degree of the surrounding rock of the roadway to meet the requirements of future reuse.In this paper,based on the above-mentioned 607 working face of Chaili Coal Mine,cross-harvesting roadway 236 east rail up the mountain connecting lane as the engineering background,using theoretical analysis and numerical simulation to combine the methods to study the surrounding rock deformation characteristics of the floor crossing through the tunnel.And the segmentation control technology,the main research work and conclusions are as follows:(1)The on-site observation method was used to study the pressure range of the coal seam in the upper coal seam of Chaili Coal Mine.The influence of the lead support pressure was 35m.The elastic mechanics method is used to establish the distribution force model of the semi-planar body on the boundary,and the vertical stress,horizontal stress and shear stress of each point of the rock mass are calculated.At the same time,the stresses of the rock masses at different depths are compared,and the stress distribution characteristics of the rock mass under different depths are obtained.(2)Using the limit equilibrium theory to study the damage depth of the rock mass under the influence of mining pressure,the damage depth of the floor rock mass of the 607 working face on the 23rd is 10m,and the influencing factors affecting the damage depth of the floor are discussed.At the same time,according to the actual geological conditions of the 607 working face on 23,the deformation and failure of the rock mass in the floor during the mining process are simulated,and the deformation and failure characteristics of the rock mass before and after the working face are obtained.(3)Based on the actual engineering background of Chaili Coal Mine,taking 236 East Rail Uphill as the research object,the damage law of surrounding rock of roadway is studied by elastoplastic mechanics method,and the elastic zone and plastic zone range of surrounding rock are calculated.At the same time,a numerical simulation model is established to simulate the deformation and failure of the surrounding rock under different depths under actual mining conditions.Therefore,the deformation characteristics of the surrounding rock of the roadway across the mining layer are determined under different vertical distances.(4)Propose the sectional control technology of the floor crossing across the roadway.According to the different distance between the roadway and the coal seam,divide the roadway into three sections of 6-10m,10-20m and 20-30m,and propose the use of Siamese rafts.Sectional control scheme for single raft and bolt(cable)support.At the same time,for the reuse problem of the corresponding roadway in the future,the reinforcement support technology of 6-10m and 10-20m sections is studied,and corresponding support measures are proposed for different sections.