Abstract:

Based on the measured data of geostress and engineeringgeological conditions at a hydropower station, possible factors affecting the initial geostress field were discussed. Under individual effect of factors, the established 3D simplified geological model was calculated by FLAC^3D. Then, a multivariate regression model was established between the measured and calculated results of geostress at measurement points. Through multiple regression analysis, the optimumregression coefficient could be derived. Thereby, the distribution tendency of the initial geostress field can be obtained. In order to show the influence of area coverage on initial geostress, a large and small model in the engineering region were  separately calculated. The numerical calculation results indicate that it is necessary to select a large model for the geostress regression of engineering in the alp region. The function of initial stress in the engineering region can be obtained from the statistical analysis of stress by using SPSS.

Key words: hydraulic engineering; initial geostress; FLAC^3D; regression analysis; SPSS