Soil–structure interaction effect on seismic response of controlled asymmetric buildings

Lateral torsional coupling of asymmetric buildings governs their seismic response. Other than building eccentricity, the extent of this impact depends on the interaction of the building foundation with the surrounding soil – soil–structure interaction (SSI). This study investigates the seismic response of a representative asymmetric building, equipped with semi-active dampers, by accounting for the effect of SSI. Two semi-active damping schemes – friction-type and two-step viscous – are considered and their relative efficiencies are measured when compared with passive dampers. All analyses, including building eccentricity, SSI and dampers, are performed under ten earthquakes with different characteristics and peak intensities. Results obtained imply that SSI can have a significant impact on the lateral torsional coupling of the building if not realistically considered, and thus can greatly influence the seismic response of an asymmetric building. Comparative assessment between semi-active and passive dampers, with respective optimal damping parameters and placement, reveals the superiority of friction-type dampers over the others in reducing the response of the asymmetric building during seismic shaking. Nevertheless, all dampers are found to be efficient in regulating the seismic response of the asymmetric building–SSI system by lowering the adverse effect of lateral torsional coupling on the seismic response of the building.