A Study Of Failure Mechanism Of Stopping Roadway And The Related Solutions In Hongshiyan Coal Mine

Mechanism of floor heave in soft rock roadway is a difficult issue in mining field, sostudying coal mines stopping roadway failure mechanism and support technology is of greattheoretical significance and engineering practical value. Through field research, observationand theoretical analysis, we study the deformation failure mechanism in working face returnair laneway12406in Hongshiyan coal mine. Then reinforcement and maintenance schemesare put forward to return air laneway12407.After field research and observation, we did detailed description on damage conditions inreturn air laneway12406, where the damage has appeared but the floor has not been shoveled.The observation tells that the degree of damage varies and conditions differ greatly accordingto different zonesDue to the trait that different failure mechanisms result in different damages and researchon geologic structure of the roadway, this roadway goes through two geologic sections andgeologic structure influences the roof and floor rock thickness and its joint developmentgreatly. The influences lead to different roof rock caving conditions in different zones ofworking face12405goaf, and then surrounding rock in12405return air laneway is underdifferent stress; by hydrological environment investigation, we know roadway’s hydrologicalenvironment is fine, so it is impossible that floor heave results from swelling after contactingwater; after experiments on roof and floor and coal lithology, we learn that roof rock is harderwith good self-supporting ability while floor rock is softer. The floor rock is vulnerable to bedamaged to be heaving floor under two sides’ high stress, which matches the filed observationperfectly. Through the relationship between floor heave and mining time, as well as Rankine’searth pressure theory, we analyze the floor heave failure mechanism affected by mining.Finally floor heave failure mechanism in12406return air laneway has been decided and thedeformation is extrusion flow type. Combine dialectic analysis of various solution schemes for floor heave deformation andthis laneway’s deformation traits, we decide the solutions of grouting, reinforcement anddigging pressure relief groove in12407return air laneway to avoid similar deformation to12406laneway. Flac3D software is adopted to simulate and then compare the surroundingrock force distributions and displacement changes under unsupported situation, originalsupporting scheme and solutions scheme. Finally, the reasons for original scheme’s instabilityand new scheme’s feasibility have been decided.