Analysis Of Seepage And Stability Against Deep Sliding For The Gravity Dam On Complex Foundation

As time passing on, all working conditions (such as structure. foundation environment) of built dams change constantly, and the safe status of dams varies too. In this article, seepage and stability against deep sliding are studied and discussed in detail as regard to Dongzhang Dam which has glacis weak surfaces in the dam foundation, some valuable results are obtained. The main contents are as follows:Firstly, the principal theories and methods to analyze monitoring data and about finite element method applied in seepage are illustrated in the article, which provide warrants in theory on choosing reasonable seepage control measure and evaluating safety reliability of dam project.Secondly, the article discusses the fundamental theories and methods to optimize seepage coefficient inverse problem. It develops computer program in seepage inverse problem-optimize arithmetic (DFP method).'Thirdly, the seepage monitoring data of Dongzhang Dam are analyzed with Stepwise regression method; the origin of some abnormal uplift pressure drill holes is studied. The factors affecting seepage are revealed and several disadvantages will be controlled. Some conclusions are drawn and suggestions put forward, which provide a good basis for safe operator of dam.Fourthly, with the optimized seepage coefficient, the seepage state of Dongzhang dam foundation and effect of grouting are appraised by comparing several different seepage control schemes, and then some seepage control measures are concluded.Finally, the stress and strain distributions of dam foundation in which there have glacis weak surfaces are studied by means of nonlinear FEM. With deducing parameters of weak surfaces gradually, stability of the dam against deep sliding is verified. Therefore safety of dam and foundation would be estimated.