Seepage And Stability Analysis Of Plain Reservoir Anti-seepage Using Geo-membrane

Because of the influence of the soil, the plain reservoirs along the Yellow River have serious problems of leakage; geomembrane used in seepage control has become a common engineering measure. Although the geomembrane has the advantages of well seepage control, high capacity adapting to the deformation, corrosion resistance, frost resistance.etc, it performances geomembrane defects easily in laying and using. These geomembrane defects are very small and hard to be found, causing inconvenience to reservoir seepage and stability analysis. The influence of geomembrane seepage to dam studied lately in Domestic, especially the study of geomembrane defect leakage was from1980s and still in a state of half experience and half theory.Based on referring to a large number of domestic and foreign references, summarizing and analyzing predecessors’ research results, this paper studied the impact of various factors of geomembrane defects to seepage and stability analysis. The seepage and stability of geomembrane in seepage control is studied by finite element method, mainly for the following:1、The saturated-unsaturated seepage analysis method is discussed, and the soil water characteristic curve and the estimation method of osmotic coefficient equation abroad is introduced in detail.2、Based on all kinds of influence factors to geomembrane defects leakage, the theory of geomembrane thickness equivalent transformation is used to build finite element. The hardness of numerical simulation of thickness geomembrane is solved. The finite element model of geomembrane in seepage control is established. Discussing the dam’s steady seepage field with geomembrane by numerical simulation, and the difference of seepage analysis results between considering the ansaturated seepage field or not.3、Seepage and stability analysis is done to the dam and its foundation by using experience formula method and finite element method. Compared with the engineering practice, analyzing the advantages and disadvantages of various methods, and analyzes the advantages of the geomembrane in seepage control by calculation.4、The influence of geomembrane defect to leakage fluxes,seepage line, as well as the stability of the dam slope is studied. The influence of geomembrane defect location, size, intensity and the condition of geomembrane in contact with layer soil to seepage parameters as well as stability respectively is analyzed. The influence of dam drainage layer to stability is researched.