Abstract

As urban populations grow, cities face the challenge of accommodating diverse typologies of structures in increasingly smaller spaces. Traditional seismic analysis considers buildings as stand-alone structures with no adjacent buildings (i.e. Soil-Structure Interaction); however, this is not representative of modern city planning. So, considering the dynamic interaction between neighbouring buildings through the common soil, known as Structure-Soil-Structure Interaction (SSSI), has become an important issue in recent years. This research investigates the influence of the dynamic SSSI on the seismic response of two structures, where one of the buildings is considered base-isolated. A discrete nonlinear low-fidelity parametric formulation that accounts for various building and soil parameters is proposed, facilitating extensive scenario exploration. The complex nonlinear behaviour of the lead rubber bearings is modelled using the phenomenological Bouc-Wen formulation, which can effectively simulate the rubber’s stiffening at large strains and strength degradation properties. The parametric explorations of the nonlinear system consider 17 strong ground motion records. Over one million response-history analyses evaluate SSSI impact on seismic responses while distinguishing between nonlinear SSSI and SSI analyses and identifying key governing parameters. When the interaction response scenarios are considered, the SSSI effects may amplify seismic displacements and accelerations by as much as 20% and 70%, respectively. The results presented here improve our knowledge of SSSI in urban seismic risk management since they reveal significant amplifications in the isolated building caused by the nearby structure. © The Author(s), under exclusive licence to Springer Nature B.V. 2025.