Coupling numerical simulation method of seepage-damage-stress for coal and rock mass water injection

Abstract

The invention discloses a water injection seepage flow in coal and rock mass zoning, damage-stress coupling numerical simulation method, according to the geological survey results, the coal seam modelis established; water injection seepage flow in coal and rock masses in non-mining affected area and mining affected area is simulated by zoning. In the non-mining influence area, the program can judge whether the coal body is deformed or even fractured under the action of water pressure stress by calculating and comparing the tensile and shear moments of each grid. At the same time, the meshlessmethod is used to simulate the fracture process of coal mass and the boundary element method is used to simulate the seepage process, which combines the advantages of the two methods on the micro-scale. In the mining-affected area, N-S equation and Darcy's law to accurately simulate the coal and rock mass water injection process in the coal and rock mass damage and moisture transport law. A soliddata basis for coal seam water injection is provided, greatly reducing the possibility of coal broken into dust particles, reducing the production of coal dust, ensuring the safety of coal seam mining.

Description

technical field [0001] The invention relates to the field of mine rock mechanics, in particular to a numerical simulation method for water injection seepage-damage-stress coupling in coal and rock mass with geological structure. Background technique [0002] Coal seam water injection is the process of injecting pressure water and aqueous solution into the coal body through drilling holes. The wetting effect of water increases the plasticity of the coal body and weakens the brittleness. The possibility of coal being broken into dust particles is eliminated, and the generation of coal dust is reduced. The whole process involves multiple disciplines such as computational fluid dynamics, fracture rock mechanics and fluid-solid coupling, and the process of numerical simulation is relatively complicated. [0003] At present, most of the numerical simulation studies on water injection in coal seams are carried out from a macro perspective, and the law of water migration in coal is...

AI Technical Summary

Problems solved by technology

However, as a typical porous media material, the essence of coal wetting is that water enters the many fine pores in the coal body, and the simulation from a macro perspective cannot reproduce this process for in-depth research

Moreover, most of the research on water seepage in the prior art is based on finite element or discrete element analysis alone, but finite element is difficult to realize coal fracture, and discrete element cannot accurately describe the seepage process and water increment data

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