Study On Stability Of Surrounding Rock Of Three-soft Coal Roadway And Supporting Technique In Xinyi Coal Mine

Along with the mines toward deep level in China,the problems of soft rock are becoming more and more outstanding, especially controlling surrounding rock of three-soft coal seam. In this thesis, based on many relevant materials, in-situ investigation, the soft rock tunnel engineering properties, character and influencing factors of buckling deformation are summarized. Based on the domestic and foreign research existing state and the geological condition of 11011 gateway in Xinyi Mine, Ltd. Adopting the combining method of laboratory and industrial experiment, the characteristics of tunnel stress distribution and roadway deformation are studied under the complex stressed state. Surrounding rock stress was measured in-situ and geomechanics was evaluated. Use the numerical simulation software FLAC3D. Simulating the displacement, stress distribution and surrounding rock plastic zone in different forms of support, finally the best support and rational support parameters are chosen. The micro arch roadway I-beam steel support is adopted and arranged along the bottom of coal seam when the impact is weak or no impact tendency and coal seam is hard-and-thick. The valgus leg U-shaped tent support is adopted and arranged the middle of coal seam when the impact is medium. The circular support is adopted and arranged along the top half of coal seam. At last, the in-situ industrial experiment is carried in 12011 coal transportation lane. The result indicated that the deformation of surrounding rock can be controlled very well and supporting effect was remarkable. It shows that the support project is reasonable.