Research On Large Section Stratification Roadway Stability Evolution And Controling Technology In Western Deep Mine

As we all know, China’s western coal seam occurrence is mainly shallow overburden condition, but near the Yushen coalfield region where coal seam buried depth is about 600-800 m, which is typical western deep mine, and the roof is a composite roof and stratification development, and the roadway deformation is large and prone to occur roof fall accident, which are belong to difficult control conditions and seriously influence the safety and high effective production of the mine. Therefore, this paper combined with characteristics of roadway with large section and buried depth or surrounding rock with development layered joint and low overall strength in Mongolia Shilawusu coal mine of Yanzhou mine, appling the method of theoretical analysis, numerical simulation and field measurement analysis the law of large section roadway surrounding rock stability and evolution and its support control technology in western deep mine.Based on characteristics of roadway surrounding rock has identified layered joints and layer thickness is small and poor cementation, this paper carried out theoretical analysis make clear the mechanical properties of composite roof roadway with large section, applied elastic-plastic mechanics to anasylis the mechanism of composite roof deformation and failure, and gained the stability conditions of composite roof rock.Numerical investigation is carried out to analyze large section roadway of western deep mine deformation law under the conditions of roof different lithology and soft rock different thicknesses. The results showed that the roof strata lithology has a greater impact on the surrounding rock stress and stress concentration area; with the roof soft rock thickness increases, the shear stress’ span and thickness in the direction of roadway roof is increased, and the amount of displacement of roof is also increased. Because of weak rock interlayer adhesion is weak and its developed joint fissures, roof strata prone to shear slip along the contact surface under the effect of shear stress, and undermined the stability of surrounding rock eventally.According to deformation evolution law of large section roadway of western deep mine, proposed excavation by steps controlling technology of large section roadway of western deep mine, and analyzed the influence of excavation by steps to large section roadway deformation, and optimizated the support parameters for the large section roadway, and determined the roadway support programs.Industrial experiments were carried out which was combined with the engineering instance, and the coupled support program of anchor and shotcreting were using to practice, and which were monitoring and analysis. The results showed that the support system of anchor, anchor and rock formation could bearer timely and control the deformation of the surrounding rock, and achieved geeater control effective.