Analysis of coupled seepage and stress fields in rock mass around the Xiaowan arch dam

摘要

The Xiaowan arch dam, with a maximum height of 292 m, is located across the Lancangjiang River in Yunnan Province of China, and once completed will be the highest arch dam in China. Because of the high water head and the arch action, it is necessary to analyse the interaction between seepage and stress fields in rock mass around the Xiaowan arch dam. Numerical solution of coupled seepage and stress fields in rock mass around the Xiaowan arch dam is analysed by means of the multi-level fracture network model and the finite element method. It can be shown from the computation results that storage of the reservoir makes the seepage field change much, and makes the effective vertical stress in rock foundation near the dam and the tensile stress in the abutment rock mass increase, and that the coupled action between seepage and stress fields should be taken into account.