基于地应力实测值的断层构造区域地应力场有限元回归反演分析

结合四川省长河坝水电站地下厂房硐室工程，考虑地形、地貌与断层等地质构造，建立了三维有限元模型，基于实测地应力值，采用多元线性回归分析方法对地应力场进行反演，以分析地下厂房区的地应力分布情况.结果表明：地下厂房硐室岩体地应力的实测值与有限元法所得反演值吻合较好，回归分析方法适用于对地应力场的反演；工程区域的水平地应力大于竖向地应力，并且地应力量值随着垂直埋深与水平埋深的增加而增大；断层附近的地应力出现了局部应力集中现象，须引起注意.

Finite Element Method Regression Back Analysis of Initial Stress Field in a Large Underground Chamber Area

Based on the measured initial stress, topography, geomorphology, and geological structure such as fault, a 3D FEM model was established for the multivariable regression back analysis of initial stress field in the underground powerhouse area of Changheba Hydropower Station. The results show that the FEM regression stress values are in good agreement with the measured values of the rock mass in the underground chamber area, and the regression method is effective for the back analysis; the horizontal stress is larger than the vertical stress, and the initial stress increases with the horizontal and vertical depth; and stress concentration appears near the fault, which should be paid attention for.