DYNAMIC ANALYSIS OF 2-D STRUCTURES USING DIRECT TIME INTEGRATION

Abstract

A two-dimensional dynamic study for elastic response of gravity dam has been carried out here. The study has been confined to plane-strain case of the non-overflow section of the dam. A test model idealized from an earth dam has been studied for a fixed ground acceleration and results are veri-fied. A mathematical model has been constructed for Koyna dam with the help of discretizat ion procedure of finite element method using 8-noded isoparametric elements. Other finite element idealized models considering foundation for different depths are also taken-up for studying the dynamic behaviour. The dynamic analysis includes the study of the dam with or without the hydrodynamic effect of the redervoir water, with fixed boundary condition. All the Koyna Dam models have been subjected to the Koyna Earthquake (Dec. 119 19679 transverse component) and dynamic responses are determined. All numerical works involved in determining the respon-ses in terms of displacements and stresses include the finite element technique for discretization of the system and the direct step-by-step implicit integration scheme for numerical integration of the equation of motion.