Influence of soil-structure interaction on the dynamic behavior of a structure subject to seismic action

Resumo

The soil-structure interaction (SSI) is present in the structural analysis in the coupling between structure,
foundation, and the soil. The consideration of this interaction is important in studies involving seismic events,
considering that the structure interacts with the soil, which alters the structural response. Attentive to the damages
caused by dynamic loads coming from the ground, the study aims to compare a structure receiving excitation
directly at the structure without considering the effects of SSI and another case considering these effects. The
excitation would be represented by an already known seism. The structures of the two situations would, firstly, be

modeled in discrete spring-mass-dampener systems and solved through the state-space method for a linear time-
invariant system. This solution method allows solving problems composed of a set of input, output, and state

variables from first-order differential equations in a matrix form. The two models were implemented in Matlab
Software. The results were expressed in the time domain via state-space and frequency by applying the Fast Fourier
Transform (FFT) in terms of displacement and velocity. The results were compared to verify the influence of SSI
on the dynamic response of the structure, which was shown to be beneficial to the structure.