Heterogeneous Random Crack Model And Coupled Process Analysis Of Seepage Field And Stress Field In Coal Mass

Gas drainage not only solves environmental pollution and energy waste caused by gas discharge,but it also reduces coal seam methane content and eliminates danger of gas outburst or explosion. Coal body conceives a large amount of fracture and random cracks which can greatly affect and even control coal mechanicals and seepage property. The effect and control of coal anisotropic and its internal random crack on gas drainage requires numerical approach to analyze gas movement in coal bed, and must take anisotropic mechanical property and internal random crack spreading consideration. Only by this way, can calculating result provide engineering value. It is evident that scientific simulation on anisotropy coal reservoirs’mechanical property and random crack spreading is the key for theoretical research and engineering design of coal seam gas drainage’s numeral applicationThe article takes it as an aim to build a representation model of anisotropic and random cracking coal body. The research content as follows:1. Build coupling model of coal deformation and gas movement through research of gas seepage property in coal.2. Through research on statistic distribution principle of coal block’s mechanical index, build probability model concerning mechanical property by utilizing Weibull distribution to simulate anisotropy of coal’s mechanical index, consequently form anisotropic seep stress coupling model of coal considering the anisotropic coal.3. Research simulating means of random crack in coal, and build probability representation model of random crack coal, furthermore, develop a seep stress coupling model of random crack coal.4. Above all, setting up representation model of anisotropic an random crack coal,providing generating steps of anisotropic and random coal body, programming relative virtual coal body generation.5. Set up random probability model of anisotropic coal concerning mechanical index relevance with experimental research on related principle of mechanical index in coal. 6. Discuss the peak post softening feature of coal and expansion,build peak post softening model of coal and expansion model with concern of confining pressure, and achieve the goal under FLAC.