Seepage-Stress-Damage Coupled Model of Coal Under Geo-Stress Influence

摘要

In the seepage-stress-damage coupled process, the mechanical properties and seepage characteristics of coal are distinctly different between pre-peak stage and post-peak stage. This difference is mainly caused by damage of coal. Therefore, in the process of seepage and stress analysis of coal under the influence of excavation or mining, we need to consider the weakening of mechanical properties and the development of fractures of damaged coal. Based on this understanding, this paper analyzes the influence of damage on mechanics and seepage behavior of coal. A coupled model is established to analyze the seepage-stress-damage coupled process of coal. This model implemented into COMSOL and MATLAB software to realize the numerical solving. Two examples are adopted to verify the correctness of the model and some useful conclusions are obtained. The numerical model establishes the relationship between microcosmic damage evolution and macroscopical fracture and simulates the whole process of coal from microcosmic damage to macroscopical fracture, and the dynamic simulation of fluid flow in this process. It provides a numerical tool for further research on the seepage-stress-damage analysis.