ABSTRACT

Base on the assumptions that Yang’s modulus, Poisson’s ratio, compressive strength, friction angle, permeability and porosity pressure coefficient to obey the Weibul distribution, a finite element model of water seepage in full-mechanical top-coal caving is built. Numerical simulation of water seepage field in over broken rock of gob is carried out by RFPA (rock failure process analysis), respectively in both vertical and horizontal planes. The calculation results show that the gob is divided into three areas, namely: natural accumulation area, structure supporting area and compaction steady area. This is in accord with mining site practice perfectly. It indicates that the O-ring of the over broken rock in gob, about 20 meters in width, is the main channels of water seepage. The flow velocity of water is directly proportional to water pressure in the process of water inrush. It has important reference value to study the water seepage and water disaster in gob.