Abstract:
In the past, embankment dams were preferred in wide valleys up to modest heights only. The advancement of soil mechanics ,evolution of earth and rockfill dams and improved design procedures have gradually lead to construction of high embankment dams in narrow gorges with steep side slopes, unfavourable foundation conditions and seismic areas. A number of dams higher than 200m have been constructed in the recent past. Detailed and comprehensive analysis of the dam duly considering all aspects into account is required for a safe structure.
Limit equilibrium approach is extensively used ignoring the deformability characteristics of the material and concentrating on the collapse mechanism. This method fails to evaluate the stress and deformation condition in the dam and could not take nonlinearity aspects of the soil into account. The Finite Element Method (FEM), at its present stage of development, is a powerful tool in the hands of dam designer. It enables the computation of stresses and strains within the dam, taking variation of properties of materials in different zones and foundations into account, as well as the effect of sequential construction. Nonlinear FEM approaches which establish the constitutive relation provide more realistic and accurate behaviour of the dam under static as well as dynamic loading conditions.
