The Study On Water Inrush Through Instability Faults For Caol Minging Above Confined Aquifer

Many coal mine in our country suffers from the Ordovician period Karst containing water inrush frequently due to the complex geology condition, Water inrush is a serious disaster in coal mining. Along with the mining deeply and the scale extends, the disaster of water inrush increasingly seriously. The large quantity instance indicate that great majority disaster of water inrush in coal mining above confined aquifer have the direct relation with fault. Therefore, study on the deformation and breakage law of upper and down floor of coal layer ,the character of formation ,each fault factor are the key problem for prevention the water inrush.Based on the study about the mechanism of water inrush from coal seam floor in coal mining above confined aquifer and the compute principle and compute method of finite element method, mechanics model is made about displacement and failure on wall rock which contain fault, and FEM calculation program is made with "Fortran". With the method of numerical simulation, the paper studied systematically the distributing law on the stress and displacement of upper and down floor of coallayer, coal pillar and fault; through analysis each fault factors which influence water inrush, gained relation that each factor influence water inrush, and the relation that between the remaining coal pillar and the factors. Under the certain conditions of other factors, the regulation of correlating is studied on the faults' dip angle, thickness and fall with the remaining reasonable coal pillar.Numerical simulation for coal mining above confined aquifer is advantageous for us to offer rational waterproof coal pillar and mining scheme, to improve productivity and escape accident of water inrush.