Earthquake-Induced Structural Pounding Between Two Inelastic Sdof Structural Systems

Abstract

Earthquake-induced pounding among contiguous building structures with insufficient separation distance, common in highly populated areas, may generate large impact forces that can significantly modify the overall dynamic behavior of the intervenient buildings. Serious structural damage or global collapse is among the negative consequences of building pounding. Inelastic behavior is inherent in building structures subjected to moderate to severe seismic excitations. Hence, the consideration of the inelastic behavior of building structures in the occurrence of pounding is extremely important to obtain more realistic results in the study and modeling of these phenomena. To this end, a Matlab-Simulink model was developed to emulate the elastic and inelastic behavior of two lumped mass SDOF structural systems under an earthquake excitation, where pounding is likely to occur. Using a smooth hysteresis model different hysteresis cases will be considered in the inelastic behavior of the structural systems, namely, stiffness degradation, strength deterioration, and pinching effect, arising in cyclic behavior of materials that compose civil engineering structures. A non-linear viscoelastic impact model will be used to assess the magnitude of pounding forces and their relation with the interpenetration depth. It was verified that the consideration of elastic behavior in buildings prone to pounding overestimates the magnitude and number of impacts that the structures experience, and underestimates structural displacements, especially in flexible structures.