Soil-Structure Interaction, A Case Study of a Building in Cochabamba, Bolivia

The present investigation studies the incidence generated by the soil-structure interaction (SSI) in an existing building located in Cochabamba, Bolivia, following the implementation the proposed FEMAP-2091 models. In this sense, the structure was verified with seismic analysis methods, examining that the inelastic drifts do not comply with the value established for reinforced concrete. Next, the significance value of SSI was analyzed, indicating that the inertial effect is significant, and the SSI models can be applied. The real system was analyzed by separating the kinematic and inertial interaction. Initially, the kinematic interaction was incorporated with two variables: the reduction due to the foundation connection and the embedment effect, which reduces the design spectrum. On the part of the inertial interaction, the dynamic stiffnesses were calculated with the impedance functions of ASCE 4–17. The SSI variables were incorporated into the models proposed by FEMA P-2091; the first two models were performed by linear analysis, and the other three models were performed with nonlinear pushover analysis. The results indicate an increase in the structure's fundamental period when considering the soil's flexibility. Such a decrease generates a decrease in the seismic demand, a decrease in the drift range of 19.9–62.4%, and an increase in the period from 0.036 to 1.155% with the implementation of the SSI models.