This research presents a nonlinear coupled analysis of a dam-reserviour problem with aspects of class I coupling for fluid-structure interaction and class II coupling for soil-pore fluid–structure interaction under earthquake excitations using finite element method. The analysis involves the compressibility of water, the flexibility of the dam, the earthquake excitation, the structural damping and the material nonlinearity on the response.
An efficient computer program is developed for this analysis from the original computer code named as MIXDYN. The new software for analyzing the coupled behaviour is established using the pressure formulation for modelling of fluid and the u-p formulation for modelling of soil-pore fluid.
Two differenent schemes for coupled field problems are implemented in the new computer code using the staggered partitioned solution technique in terms of sequential execution of single-field analyzers .Eight-nodded two-dimensional isoparametric element is adopted for idealization each of soil, fluid and structure. The Drucker Prager model is used to simulate the behavior of soil and concrete. Implicit-Implicit Newmark’s scheme with corrector predictor algorithm is employed for time integration of the equations of motion. The capability and the efficiency of the model are found to be very useful.