en Geotechnique Geotechnique Research Paper Research Paper <p class="a"><span lang="EN-CA">The distinctive characteristics of near-field earthquake records can lead to different structural responses from those experienced in far-field ones. Furthermore, soil-structure interaction (SSI) can have a crucial influence on the seismic response of structures founded on soft soils however, in most of the time has been neglected nonchalantly. This paper addresses the effects of near-field versus far-field earthquakes on the seismic response of single degree of freedom (SDOF) system with considering SSI. A total 71 records were selected in which near-field ground motions have been classified into two categories: first, records with a strong velocity pulse, (i.e. forward-directivity) second, records with a residual ground displacement <a name="OLE_LINK2">(i.e. </a>fling-step). Findings from the study reveal that pulse-type near-field records generally produce greater seismic responses than far-field motions especially at high <a name="OLE_LINK65">structure-to-soil stiffness ratio</a>s. Moreover, the importance of considering SSI effects in design of structures is investigated through an example. Finally, parametric study between Peak Ground Velocity to Peak Ground Acceleration ratio (PGV/PGA) of pulse-like ground motions and maximum relative displacement indicate that with increase in structure-to-soil stiffness ratios, earthquakes with higher PGV/PGA ratio produce greater responses.</span><!--stripped--><!--stripped--></p> Soil-structure interaction, SDOF system, Near-field earthquake, Far-field earthquake, PGV/PGA 153 166 http://ijce.iust.ac.ir/browse.php?a_code=A-10-326-2&slc_lang=en&sid=1 M. Davoodi m-davood@iiees.ac.ir 1800319475328460010436 1800319475328460010436 Yes International Institute of Earthquake Engineering and Seismology M. Sadjadi mani.sajadi@yahoo.com 1800319475328460010437 1800319475328460010437 No International Institute of Earthquake Engineering and Seismology