ANALYSIS OF NUMERICAL SIMULATION METHOD FOR PALEO-TECTONIC STRESS FIELD

This paper analyses the numerical simulation method for Paleo-tectonic Stress Field from three aspects, namely tectonic simulation target, building of the tectonic model and tectonic modeling. Taking Chengzhuang coal mine, Jincheng City of Shanxi Province as an example, and based on field investigation on macro- and micro-tectonic features, the authors have established a plane-strain and three-dimension geological model, and obtained the mechanics parameters and fracture criterion of rock and boundary condition of the model. Using the large numerical simulation analysis software such as ANSYS and FLAC, they have determined the magnitude of palaeo-tectonic stress as the boundary condition of model and the loading sequence of palaeo-tectonic stress. The simulation results reveal two stages of large tectonic movement in the study area, the first movement in E-W and then another in N-S. Accordingly, a tectonic stress of 60 MPa was imposed in E-W deirection and 110 MPa in N-S direction. The acting pattern of the stress caused the simultaneous appearance of most shear joints on the earth surface and in the 3^# coal rock. These rules not only offer important reference for understanding of deep condition of coal and the gestation condition of move fault in coal, but also have great significance for prediction of coal and gas outburst in stress concentration area of rock mass.