Experimental Study on the Cyclic Performance of Novel Seismic Base Isolators Made by Scrap Tire Rubber Pads

To provide cost-effective protection for low-rise buildings, an alternative approach involves the utilization of sustainable and economical seismic base isolators made from scrap tires. This study aims to examine the performance of experimental specimens of three distinct types of scrap tire rubber pad (STRP) isolators when subjected to both gravity and lateral cyclic loads. One of the isolator specimens was fabricated without adhesive between the stacked rubber layers, whereas the remaining two specimens featured bonded rubber layers. In one of these innovative STRPs, layers of rubber and steel were connected using adhesive, while in the other one, the rubber layers were bonded together while incorporating four steel rods at the corners of the isolator. The inclusion of these rods serves to dissipate seismic energy through friction. The findings of this investigation indicate that the base isolator featuring steel rods exhibits the most favorable performance, with a significantly low construction cost of approximately $400. It demonstrates the second lowest effective horizontal stiffness (0.28 kN/mm), as well as the highest values for other parameters such as effective damping (0.24), vertical stiffness (12 kN/mm), and total dissipated energy (11,692.41 kN.mm) when compared to the other two STRPs. Therefore, it can be concluded that this specific STRP isolator effectively mitigates the destructive effects of earthquakes on low-rise buildings.