Rule Study on the Risk of Floor Water Inrush Based on the Plate Model Theory

Abstract

In order to mitigate the potential issue of abrupt water inrush in coal mining operations, the elastic-plastic mechanics theory was employed to simplify the water barrier of the floor strata into a thin rectangular plate. Subsequently, a fluid-solid coupling damage model was designed through the utilization of COMSOL Multiphysics software to investigate the coupled seepage and damage effects of the rock mass in an equivalent continuous medium. The results indicate that (1) the analysis of the theoretical equation of elastic mechanics shows that the fracture position of the four-sided clamped thin plate is in the center of the four sides, and the theoretical limit span and the theoretical limit water pressure formula are derived. (2) The damage factor is used to characterize the damaging effect of different mining distances and different pore water pressures on the rock mass of the floor aquiclude in the numerical simulation. It is found that the damage tends to the open-off cut and stop-mining line of the floor waterproof layer and the center position on both sides of the coal wall, and the stress is the most concentrated. (3) The results obtained by the two research methods are highly consistent, which provides a theoretical basis for the prevention and control of water in ground mining mines, so as to realize safe mining above the confined aquifer.