Study On Surrounding Rock Stability Control Technology Of Mining Roadway In Three Soft Coal Seams

The fourth layer of coal in Daliu Coal Mine is a typical three-soft coal seam,and the surrounding rock of its mining roadway has large deformation,long deformation time and fast deformation rate.In order to ensure that the mining roadway can meet the normal production requirements,it is often necessary to increase the section area of the roadway by means of roof lifting,undercover,sheet wall,etc.The existing supporting methods do not effectively guarantee the stability of the surrounding rock of the mining roadway.Through the analysis of the support scheme of 1405 return air corridor roadway,the water softening test of roadway floor rock,the pressure monitoring of anchor bolt and cable support,and the detection of loose circle of roadway surrounding rock,the factors affecting the deformation and failure of mining roadway in three soft coal seams are analyzed.It is pointed out that insufficient support strength,water softening of floor,influence of advance abutment pressure in mining area and no effective improvement of bearing capacity of roadway surrounding rock are the main factors affecting floor heave,slab wall and roof collapse of mining roadway in three soft coal seams.According to the influencing factors of deformation and failure of mining roadway in three soft coal seams,a new combined support technology of anchor net injection and single hydraulic prop temporary support is put forward,and its mechanism is analyzed.Through Abaqus numerical simulation calculation,the roof subsidence,floor heave and wall convergence of mining roadway in three soft coal seams are analyzed under the new support scheme,and the preliminary judgment is that the support scheme can effectively ensure the stability of roadway surrounding rock.Through the analysis of the deformation and failure of the surrounding rock of the mining roadway of the third soft coal seam under the new support scheme,it is further verified that the bearing capacity of the surrounding rock of the mining roadway of the third soft coal seam under the new support scheme has been improved and the deformation has been well controlled.By analyzing the factors affecting the deformation of the surrounding rock of the mining roadway in three soft coal seams,a new roadway combined support technology is put forward.By analyzing the action mechanism of the new support,the scientific nature of the new support scheme is verified,and the effectiveness of the new support scheme is verified by numerical calculation and field industrial test.The research results have certain reference value for guiding engineering practice.Figure 45 Table 12 Reference 92...