dynamic soil – structure interaction analysis of concrete structures by using finite elements method

in practice, foundations are settled on the soft layers of soil, so the ground must be designed as well as the structure. wave propagation and hysteresis damping of soil layers may alter the seismic response of flexible-base design in comparison to controversial fixed-base. lots of uncertainties about this issue, necessitate most of seismic design standards including iranian standard no. 2800 to neglect the soil – structure interaction (ssi) effects on seismic response of structures. a simplified finite elements method is proposed in this research and applied according to the standard no. 2800 criteria on reinforced concrete structures. the accuracy and efficiency of this method is compared with four other similar researches, and the results of time history and modal analyses for descriptive reinforced concrete systems are ilusterated in the form of figurs and charts.