Structural pounding in the seismic vulnerability of buildings located on soft soils

Abstract

This study analyzes the effect of structural pounding on the nonlinear dynamic response of buildings located in the soft soil zone of Mexico City when subjected to seismic actions.To this end, the structural typologies to be studied were identified, and their behavior was evaluated through incremental dynamic analyses that is, nonlinear step-by-step analyses with a monotonic increase in seismic demand. The study was carried out using the OpenSees software, where nonlinear behavior due to lateral displacements was modeled using concentrated plasticity in the structural elements, employing the corresponding moment-curvature and moment-rotation diagrams.To represent the pounding phenomenon, a linear elastic contact-force model was used to simulate collisions between structures, assuming that contact occurs between the floor systems of adjacent buildings.The results obtained show that structural pounding has a significant impact on buildings, as it amplifies the seismic response and increases the interstory shear, which can lead to structural collapse. The information generated in this study is valuable for assessing the seismic structural vulnerability of buildings subjected to pounding and, if possible, for implementing preventive actions that help mitigate the associated risk.