Numerical Analysis of Wetting-induced Deformation for Rockfill Dams
Abstract
The wetting-induced deformation can lead to serious engineering hazards for rockfill dams. A new computaitional method of wetting-indueced deformation was proposed here to perform stress-deformation analysis on rockfill dams. Based on the resulst of triaxial wetting tests of rockfill materials, the influence of confining pressure on wetting-induced volumetric strain was considered by revising the existing double yielding-surface model for rockfill materials. The nonlinear finite element code was programmed to perform stress-deformation analysis on one concrete-faced rockfill dam under the conditions of the steady seepage and the rise of tail water table with an elasto-plastic constitutive model. The computation results demeonstrate that (i) the wetting-induced deformation of roclfill mateirals under the phreatic line has great influences on the distribution of deformation and stress in the dam body; and (ii) accompanied by the wetting-induced deformation, the settlement of dam body increases and the horizontal displacment moves towards dowmstream, the relatively higher increment of compressive stress in the face slab appears, and the peak values of both compressive and extensive stresses in the horizontal direction increase.References
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