Study On Optimization Of Anti-seepage System For Rockfill Dam On Deep Overburden Layer

Because of the topographic and climatic conditions, Chinese water resources are mainly located in the western mountain valleys, but the problem of deep overburden layer is often encountered when developing hydropower resources in west, especially in the southwestern region where has rich hydropower resources.The foundation treatment and anti-seepage technology of deep overburden layer is worth studying. But there is not a general law to deal with the problem because of the different geological condition.The paper take Luding hydropower station as the research object, on the basis of research production of predecessor, the state of seepage stability of the deep overburden layer of the dam site is studied, the characteristics of seepage field of dam site is analysised on applying 3-dimension seepage finite. the finally optimized plan is obtained on the basis of the comparation of various plans and economic evaluation. The main research content is as follows:(1) Based on the seepage control principle of" combining anti-seepage and drainage, and filter protect the export of the seepage", seepage control measures and anti-seepage system connecting form on deep overburden layer and project application are relatively system explained ,the choice of anti-seepage technology of Luding hydropower station on deep overburden layer is provided.(2) According to the basic characteristics and distribution of deep overburden layer of Luding hydropower station, its permeability and seepage stability is analysised, and the guidelines of seepage analysis and evaluation is set up.(3) Applying on 3-dimension seepage finite, the seepage of Luding hydropower station dam site is analysised, and designed anti-seepage plan is studied, it is drawn that the designed anti-seepage technology satisfies the seepage stability and seepage discharge control.(4) The anti-seepage effection of different anti-seepage plans are compared and studied ,and refer on economic evaluation,the optimized plan of seepage control is suggested,it is that abolishing the standard bedding on the basis of the designed plan. In addition, the seepage when impervion wall cracked is analysised, and design and function of filter is studied.