Sharif University of Technology Scientia Iranica 1026-3098 24 3 2017 06 01 Influence of foundation flexibility on the seismic response of low-to-mid-rise moment-resisting frame buildings 979 992 4081 10.24200/sci.2017.4081 EN H. Tahghighi Department of Civil Engineering, University of Kashan, Kashan, P.O. Box 87317-51167, Iran M. Rabiee Department of Civil Engineering, University of Kashan, Kashan, P.O. Box 87317-51167, Iran Journal Article 2015 10 24 Recent studies have shown that the effects of Soil-Structure Interaction (SSI) may be detrimental to the seismic response of structure, and the neglect of SSI in analysis may lead to an un-conservative design. The objective of this study is to simulate the performance of multi-storey building-foundation systems through a Winklerbased approach. Four typical steel Moment-Resisting Frame (MRF) buildings on three soil types with shear wave velocities of less than 600 m/s subjected to actual ground motion records of varied hazard levels are modeled with and without SSI. It is observed that the performance level of models supported by <br />flexible foundation, particularly in an intense earthquake event, may alter signicantly in comparison to fixed-based structures. Moreover, for MRFs on soft soil, the nonlinear foundation is found to have a signicant<br />effect on the force and displacement demands. This indicates the necessity for consideration of <br />flexible foundation behavior in the modern design codes in order to accomplish a more economic yet safe structural design. https://scientiairanica.sharif.edu/article_4081_584b5cb4fa10a69e40eb0bc2734e50a5.pdf