Tuning the lateral response of unbonded fiber reinforced elastomeric isolators (U-FREIS): Experimental - Numerical findings

Fiber-reinforced elastomeric isolators (FREIs) are elastomeric devices which have been introduced as a low-cost alternative to the well-known steel-reinforced elastomeric isolators (SREIs). As common in rubber-based devices, the application of FREIs to lightweight structures is challenging: when the mass is limited, the resulting slender bearings tend to become unstable under large horizontal displacements. On the basis of numerical and experimental findings, this research work aims to demonstrate a simple to implement and low-cost approach to extend the application of FREIs to lightweight structures. The technique here discussed allows (i) to reduce the horizontal stiffness of FREIs, (ii) to increase the stability range of the bearings, and (iii) to obtain a desired hardening response for large lateral deformations, with no instability.