Influences of water pressure and advance length on floor water inrush based on mechanism of fluid-solid coupling

To study the influences of the pressure of floor confined water and the advance length on the surrounding rock stress, through doing an experiment which makes researches on its changes by simulating the pressure of floor confined water respectively as 3MPa, 6MPa, 9MPa and the advance length from 20 to 380 meters, this paper, under the actions of different advance lengths and water pressures, has analyzed the basic laws of the changes of surrounding rock's horizontal and vertical stresses and predicted the damage depth of floor by the use of the rock-water relation method. The results show that, under the effects of different water pressures, as the advance length increases, the increasing scope of vertical stress of surrounding rock is larger than that of horizontal stress and the former plays the dominating role in the floor damage; the floor water inrush is the result of combined actions of ground pressure and the pressure of confined water and it is efficient for predicting the happening of mine water inrush by establishing the critical exponent of water bursting I and comprehensively thinking about the combined actions of ground pressure and the pressure of confined water.