Dynamic Calibration of the Transverse Elastic Modulus of Shredded Rubber for Use in Seismic Isolation

Abstract

Seismic isolation aims to prevent the direct transmission of seismic wave energy to the main resistant structure. Typically, this is achieved by using a flexible support system that isolates the base of the structural system from the ground, absorbing the relative deformation at the soil–structure interface. Meanwhile, the main structure tends to move as a rigid body on this flexible support. This article proposes an alternative approach for the dynamic characterization of shredded rubber, which is used in geotechnical seismic isolation (GSI). Traditional testing methods are expensive and require specialized equipment, making them less practical for routine determination. The article details the most important parameters needed to evaluate the applicability and effectiveness of the material in the context of GSI. The parameter of interest, i.e. the transverse elasticity module GR, was calibrated numerically from an experimental model of a column of shredded rubber subjected to free vibrations tests. The results were consistent with those obtained from resonant column and hollow cylinder tests. In this way, it is shown that the presented approach is capable of providing valid estimations of the transverse modulus of elasticity of shredded rubber.