Evaluation the seismic response of soil-structure interaction on based-isolated structures subjected to near-field earthquakes

Recently considerable attention has been paid to the passive control systems, which widely used to dissipate earthquake excitations without using any energy source. Base isolation is a seismic response modification technology, which was developed to mitigate the structural damage to structures. The present study is focused on the effect of Soil-Structure Interaction (SSI) on the response of base-isolated structures with and without considering a vertical component of the earthquakes. For this purpose, two-dimensional seismic Lead Rubber Bearing (LRB) base-isolated structures with 5, 10 and 15 stories, which designed according to International Building Code (IBC) provisions, have been analyzed. Accordingly, three medium-to-high-rise base-isolated structures based on a shallow mat foundation located on a soil type, IV, or I, were examined. The effect of SSI has been considered using relations derived from National Earthquake Hazards Reduction Program (NEHRP). The numerical results indicate the significant effect of the vertical component of earthquakes on the response of structures. Neglecting the vertical component of earthquakes, which have a high vertical amplitude, will result in unacceptable estimation in axial forces and energy dissipating in the seismic LRB isolator systems. Moreover, considering the SSI effects have a significant influence on the hysteresis curves

کلیدواژه ها:

Vertical component of earthquake ، Base isolation ، Soil-structure interaction ، Near-field earthquakes