Stress Characteristics Analysis of Hydraulic Fracturing Influenced Zone Based on FLAC^3D Numerical Simulation

For the problem that the implementation of hydraulic fracturing in the shaft will produce stress redistribution and affect the safe production in mining face, in order to further understand the hydraulic fracturing process and characteristics of stress distribution of coal and rock, the simulation software FLAC^3D is adopted to study stress variation in the process of hydraulic fracturing. The down hole hydraulic fracturing FLAC^3D numerical simulation show that the pressure in the ground stress is greatly reduced, on both sides of the original stress increased drilling on both sides of the displacement of coal occurrence and z direction, scope of fracturing effect reduce internal stress, appear unloading area, it is good for eliminating coal and gas outburst danger; the flaws of the down hole hydraulic fracturing is also found; the fracture tip will appear with the new stress concentration, which brings potential safety hazard for the working face.