Stress Deformation Analysis Of Seepage Prevention Oblique Wall Of Composite Geomembrane For Earth-rockfill Dam

Composite Geomembrane as a new seepage prevention material, compared with tranditional seepage prevention material, it has its own advantage such as low-permeability, high ability to adapt deformation, well stability of material, lower cost, light quality, convenient transportation, construction shortcut, sufficient source, environmental protection etc, so composite geomembrane has been widely applied in the domestic and international anti-seepage project. Especially after the "98devastating floods"in china, geomembrane and composite geomembrane get a broader understanding and a high degree of attention.In this paper, on the basis of summing up the results of previous studies, from the perspective of the composite geomembrane structure, combined with practical engineering, using the large general-purpose software of ABAQUS, three-dimensional finite element numerical calculation of the sloping wall of earth-rockfill dam composite geomembrane stress and deformation under different anchor types, different dam hight, different coefficients and different dam slope conditions, get the characeristics and law under different conditions of composite geomembrane sloping wall stress and deformation of earth-rockfill dam:(1) Composite geomembrane at the top of the dam at different types of anchoring, the anchoring end at composite geomembrane stress-strain values are the maximum, which reflects the "clamping effect"phenomenon.In different types of anchoring, anchoring the wave wall composite geomembrane stress-strain is maximum, minimum in the "U" anchor type. In practical engineering, the use of the "U" shape anchor type, stress and deformation of composite geomembrane appropriate improvement.(2) In different dam hight, especially in the high dam in the application of composite geomembrane, compared with the low earth-rockfill dam of composite geomembrane, with the dam height increases, the composite geomembrane is not only in the crest anchorage zone at the larger stress and strain, and stress-strain cross-strait anchoring at the dam height increases with increasing the anchor end at the cross-strait toe stress-strain value is reached. Simulation of the high dam situation, verify the feasibility of composite geomembrane application to the dam of one hundred meters level.(3) Composite geomembrane used in the different coefficient of friction under the conditions of the earth-rockfill dam engineering, composite geomembrane stress-strain values will change. With the increase of the friction coefficient between the composite geomembrane cushion, its stress-strain value decreases.(4) Applications in different dam slope conditions in earth-rockfill dam engineering of composite geomembrane, with dam slope steepens, composite geomembrane by the stress-strain gradually increases, its vertical displacement decreases slightly, while down the river to be increased displacement to the downstream level. With the dam height increase of composite geomembrane stress and deformation values have increased, through the simulation of the high dam, verify the feasibility of the different dam slope of the composite geomembrane used in the high dam conditions.