The role of soil-structure interaction in the inelastic performance of multi-storey buildings

A comparative evaluation study is reported of the response of a group of 3-storey reinforced-concrete building structures designed according to EC8 and EC2 code provisions subjected to a wide set of seismic excitations. The buildings under consideration employ different structural systems and have been designed as fixed-based according to current design practices. A comprehensive set of non-linear time-history analyses were performed using seismic excitations on soft soil, taking into account the soil structure interaction effect by means of a set of multi-axial springs and dashpots attached at the base of the structures. The results highlight the role of soil in the structural response and show that soil-structure interaction should always be considered in design as it leads to significant redistributions of internal member loads.