Numerical Simulation And Application Of Fault Based On FLAC^3D

China has abundant coal resources, storage conditions are very complicated, the fault affect coal mining. It is a major geological factor. Coal mining caused fault activation, coal and gas outburst and water inrush incidents occur frequently, safety and efficient exploitation of coal mine has brought problems, so searching a set of forecast methods of geological hazards is necessary, and has considerable practical significance.Fault destroyed the coal seam continuity and integrity, the stress differences distribution around the fault is great. During the excavation the displacement field, plastic zone and stress field will change. For this particular geological condition , the coal mining can not get analytical solution of stress and displacement. With the development of computer technology, numerical calculation method has been significant progress, For the complex engineering problems, numerical methods can be used. It can meet the numerical solution of various value analysis. Numerical calculation method has become a rock physical science research and important means of engineering design and calculation. When the initial conditions and boundary conditions choose reasonable, the numerical simulation can replace the expensive physical testing methods.The first part of paper, by using numerical simulation software FLAC3D simulated fault tip stress distribution and analyze the impact factors of the fault tip stress concentration. The second part of paper, 10.13 coal and gas outburst of Hebi Coal mine as studying background, to simulate stress distribution of coal mining on faults ,and analyzing the main factors of causing the accident. The last part of the paper, by using numerical simulation software-FLAC3D simulated fault reactivation and inrush of water when normal fault dip angle is different. To prevention of coal seam floor water inrush provide some useful reference.