关键词: 天然渗流场, 初始地应力场, 反演回归分析, 开挖顺序

Abstract: Based on the engineering-geological conditions and the measured data of geostress at Dagang-shan Hydropower Station, the 3D geological models under each affecting factor were calculated with ABAQUS as a tool for finite element calculation. Then, a multivariate regression model was developed between measured and calculated results of geostress at measurement points, and the regression coefficient of the model was derived. With the model, the regularities of initial geostress distribution were obtained. It is the first time to take the crude seepage field as an affecting factor. By comparing the results with that only taking into account of the effects of dead weight and tectonic function on the initial geostress field, it is found that the crude seepage field can make regression better. Comparisons of different excavation sequence were made based on the back analysis geostress, and the calculation result showed that main openings are well stable with the optimized construction sequence.

Key words: crude seepage field, initial geostress field, back regression analysis, excavation sequence