| Rock burst is a complex dynamic phenomena and one of the difficulties of research on mine disasters controlling. The number of mines in which rock burst occurred is increasing and the rock burst distribution is extending as the mining depth and intensity increases, which threatenes the production and safety of mines, so the study on controlling theory and technology of deep coal mine rock burst is immediately needed. This dissertation systematically researched the response regularity of deep thick seam roadway suffering static load and dynamic load through theoretical analysis, numerical simulation and field measurement etc, and stress, velocity, acceleration and energy distribution of roadway under impulsive load were gained. The mainly original works and achievements are as follows:(1) Stress distribution equations of double-layer and four-layer thick walled cylinder under confining pressure were deducted with elasticity theory, and finite element theory was used to analyze the stress distribution of triple-layer cylinder, also suffering confining pressure. Zoning, structure and function of coal mass in deep super thick seam and its support structure were studied. Based on those studies, we can bring forth the standpoint that roadway surrounding rock can be simplified to a"strong-weak-strong-weak(S-W-S-W)"mechanical model including the following parts: constraint circle formed by U-shaped contractible metal stents; support circle made up of bolt-mesh-cable support and surrounding rock; pressure relief and buffering circle formed after water injection or loosening blasting; fully arch circle formed by initial rock. Rock burst controlling mechanism of the S-W-S-W model was analyzed.(2) Based on the analysis of shock wave spreading characteristic, single-layer and multi-layer composite roadway surrounding rock under impulsive load were analyzed in universal explicit dynamic analysis program ANSYS/LS-DYNA. Comparison between stress, velocity, acceleration field of roadway and surrounding rock shows that the composite structure roadway containing weak interlayer has a better effect of rock burst controlling, and its controlling mechanism was analyzed.(3) Stress condition and distribution of concentrated elastic strain energy in surrounding rock of roadways with different shaped sections were analyzed by using numerical simulation, proper shapes of roadway section better for preventing rock burst and other dynamic disaster was gained. Mechanics and energy response of roadways with three different shaped sections were analyzed and compared, stress distribution and energy concentration characteristics during impulse were acquired, a feasible method for rock burst analysis can be derived from those results.(4) The rock burst controlling method of pre-excavating pressure relief chambers orient fully mechanized top coal caving face has been advanced for the first time. Proper interval and depth of pressure relief chambers were decided in numerical simulation. Pressure relief chambers and transport gateways surface displacement and stress in the bolts were measured in the field to study the pressure relief chambers design's effect of controlling rock burst. Stress in some of the pressure relief chambers and nearing roadways'roof bolts was acquired, and that confirmed the pre-excavated pressure relief chambers'effect of controlling rock burst.There are 139 figures, 20 tables and 177 references in this dissertation. |
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