Research On Asymmetric Deformation Mechanism And Control Technology Of Roadway In Inclined Soft Coal Seam

Based on the actual geological conditions of the air roadway 8204 in Guobei mine,this paper applies the methods of field investigation,laboratory test,theoretical analysis,FLAC^3D numerical simulation,industrial experiment and so on to study the"asymmetric deformation mechanism and control technology research of roadway in inclined soft coal seam".This paper analyzes and demonstrates the cause of asymmetric instability of surrounding rock of roadway,simulates roadway tunneling with actual geological conditions,analyzes the displacement change rule of asymmetric deformation of roadway in inclined soft coal seam,and proposes a new support scheme in terms of surrounding rock control combined with early roadway evaluation.The main conclusions are as follows:?1?The geological conditions and characteristics of the 8204 wind tunnel in Guobei coal mine were explained in detail.Through on-the-spot investigation,coal mine data and borehole observation,it was analyzed that the deformation amount and form of the left and right sides of the 8204 wind tunnel were quite different.The deformation amount of the right side was larger than that of the left side,and the internal cracks were more developed.?2?According to the mechanical tests of coal and rock mass conducted in the laboratory,the mechanical parameters of no.8 coal and mudstone from roof and floor were obtained.X-ray diffractometer?XRD?and X-ray fluorescence spectrometry?XRF?were used to quantitatively analyze the composition of 8 coal.?3?Analyze the cause of asymmetric failure of inclined soft coal seam,and obtain the features of asymmetric deformation,movement of surrounding rock,floor heave and asymmetric failure of roadway.The asymmetric deformation of the surrounding rock of inclined roadway is classified simply by using the simplified beam structure model of material mechanics and elastic mechanics.?4?Different dip angles of 0°,10°,25°and 40°of coal seams were selected and FLAC^3D numerical simulation was used to analyze the displacement and stress variation rules of asymmetric deformation of roadway.Numerical analysis shows that the displacement of roof and floor of roadway in inclined soft coal seam is larger than that of two sides,and the deformation of high side is obviously larger than that of low side.The maximum displacement of the roof moves to the lower side with the increase of the dip Angle of the coal seam.The floor has weak lithology and the floor heave is serious.The maximum displacement moves to the upper side with the increase of the dip Angle of the coal seam,forming obvious dislocation deformation.With the increase of the dip Angle of coal seam the vertical displacement of roof and floor decreases gradually and the horizontal displacement of left and right sides increases gradually.?5?In the bolt support,the bottom of the arch supporting numerical simulation analysis,respectively,when the end of the arch supporting of roadway deformation under asymmetry decreased significantly,and can effectively control the deformation of surrounding rock of roadway,especially to the deformation of roadway floor control effect is better.So using the bottom arch support as the way of support.?6?Combined with the simulation analysis results and the displacement monitoring of roadway roof and floor and two sides,the surrounding rock control effect of inverted arch support was verified.There are 63 figures,9 tables and 83 references in the dissertation.