In-Situ Stress Inversion Of Deep Mining Area By Nonlinear Chaotic Method

In-situ stress data is essential to mining safety, so a small-scale in-situ stress measurement was completed in Fankou mine (largest lead-zinc mine in China). Due to the high cost of in-situ measurement, in-situ stress inversion by nonlinear method was studied. Firstly, massive measured in-situ stress data was collected for fitting analysis, which revealed varying law between in-situ stress components and depth. Then, boundary condition for numerical inversion was determined. Numerical inversion model containing various geological information was built by Surpac-FLAC(3D) modeling technique. With these works, approximation function of inversed stress and measured stress was built, while the function was solved by chaotic iteration method. From this, numerical simulation for in-situ stress inversion of deep mining area was conducted. The fitting accuracy between inversed stress and measured stress exceeds 90%. It proves that nonlinear chaotic method is useful for in-situ stress inversion, which is critical for mining safety.