江坪河水电站坝址区初始地应力场三维数值反演分析

Three-dimensional numerical inverse analysis of initial geostress field at dam site of Jiangpinghe Hydropower Station

在对江坪河水电站区域地应力场特征进行实测分析的基础上,通过对三维模型施加不同的边界载荷,对比分析应力拟合点处的计算应力与实测应力,采用三维数值分析方法对水电工程坝址区初始地应力场进行反演分析。结果表明:江坪河水电站坝址区初始地应力场量值较低,最大主应力为2.5 MPa,方向为N45°W;最小主应力为1.5 MPa,方向为N45°E。应力拟合点处应力计算值与实测值较为接近,表明反演得到的坝址区初始地应力场是合理的,符合坝址区地质构造历史背景。

Based on analysis and measurement of a geostress field at the dam site of the Jiangpinghe Hydropower Station, and comparison of calculated and measured stress at the points for stress fitting, inverse analysis of the initial geostress field at the dam site of the Jiangpinghe Hydropower Station was conducted using a three-dimensional numerical model with different boundary loading conditions. The results show that the initial geostress is low at the dam site of the Jiangpinghe Hydropower Station, the maximum principal stress is 2. 5 MPa and its direction is N45° W, and the minimum principal stress is 1. 5 MPa with a direction of N45°E. There is agreement between the calculated and measured stress at the points for stress fitting, indicating that the initial geostress field at the dam site obtained by inverse analysis is reasonable and conforms to the historical background of the geological structure.