ABSTRACT
The stress field and the seepage field interact and interact with each other until they reach a dynamic and stable state. This dynamic relationship constitutes a fluid-solid coupling mathematical model. For the actual engineering rock mass, the porosity and permeability coefficient K change dynamically with different stress and strain states of the rock mass. Therefore, in the numerical calculation and analysis, the dynamic change of the permeability coefficient should be considered so that the calculation results can be more in line with the actual engineering. According to the characteristics of the water softening of coal and rock, the fluid-solid coupling calculation related to water content is further carried out. The calculation results show that with the increase of water content, the degree of weakening of the mechanical parameters of coal and rock mass increases, the infiltration range increases, the plastic zone extends to the deep part of the coal pillar, and the range of the plastic zone increases.
