Study On Seepage Analysis And Anti-Seepage Measures By 3-D Fem Of Bingling Hydropower Cofferdam

For earth rock-fill cofferdam and earth dams in deep overburden foundation, the problems of water leakage and seepage failure are the most important problems in design. If the design of impervious measures is improper, it may cause the problems of water leakage which can influence the normal construction in foundation pit or the problems of seepage failure of the body of cofferdam and the foundation, endangering the cofferdam. So for large earth rock-fill cofferdams which will be built in deep overburden foundation, it is necessary to design reasonable impervious measures with the help of accurate results by numerical calculation method in the process of design. This thesis which is linked with the seepage problems of the cofferdam of Bungling hydropower project, adopts the finite element theory of 3D unconfined steady seepage and analyses the problems of seepage through cofferdam and seepage bypass dam with the numerical calculation method.Chapter 1 introduces the thesis's origin and significance and summarizes the main works of this thesis.Chapter2 introduces the finite element theory of 3D unconfined steady-seepage, calculation method and the method of classifying the FEM results.Chapter3 introduces the general situation of the upstream cofferdam of Bungling hydropower projectChapter4 gives the preliminary impervious measure and the scheme to be calculated by FEM.Chapter5 gives the finite element model, boundary conditions and values of parameters for calculation.Chapter6 analyses the results of numerical calculation by FEM for seepage, gives the optimum impervious measure.