Study On The Laws Of Surrounding Rock’s Asymmetric Deformation Mechanism In Deep Roadway

With the development of coal mining to the deep constantly, large deformation and stability of surrounding rock of the deep roadway is becoming more and more outstanding. In view of the characteristics of deep roadway surrounding rock deformation, this paper adopted the method of combining the theoretical analysis and numerical simulation, the asymmetric deformation mechanism of deep roadway are analyzed.Based on the understanding of deep rock mass mechanics characteristics, considering the influence of the after rock peak strength, analyzes the support resistance, buried depth and intensity of surrounding rock of roadway surrounding rock deformation and failure, Combined with concrete examples, it is concluded that after peak strength characteristics of rock drop of modulus7changes on the development of plastic zone of surrounding rock has a great influence. In based on the analysis of the characteristics of deep engineering rock mass in-situ stress, discuss the roadway surrounding rock under the condition of different lateral pressure coefficients of the stress distribution and damage, Combined with numerical simulation analysis shows that when the lateral pressure coefficient λ≠1, the characteristics of the roadway surrounding rock stress distribution presented asymmetric, scope of the plastic zone of surrounding rock of roadway has a great difference in different locations around the roadway.On the basis of theoretical analysis, using the FLAC3D numerical simulation software recreates the asymmetry of deep roadway deformation phenomenon, combined with different lateral pressure coefficient, buried depth and different lithology and different factors such as strata occurrence, simulated analysis respectively. The simulation results show that the asymmetry of deep roadway deformation to produce the necessary conditions include:(1) high geostress,(2) tilted strata distribution,(3) layered rock structure, and the layered different lithology. Under the condition of the three, the structure of the left and right sides of the surrounding rock of roadway is asymmetry, even under the condition of symmetrical ground stress field, the roadway surrounding rock stress redistribution also presents the characteristics of asymmetric, leading to the left and right sides of roadway deformation will be different, the asymmetric deformation phenomenon. Deep high geostress, tilt, and, therefore, the heterogeneous formations, is the root cause of the asymmetry of roadway deformation, stress distribution due to the asymmetry and structure of surrounding rock of roadway surrounding rock the influence of asymmetry caused the deformation of surrounding rock of roadway asymmetry, this is the mechanism of the asymmetry of deep roadway deformation.According to the researches on the mechanism of the asymmetry of deep roadway deformation, judgment of deep roadway surrounding rock deformation characteristics, can be based on the study to judge the biggest deformation of roadway position, thus providing a certain wrong as large deformation in advance in order to support the judgment.