3D Shaking Table Tests Of A Full Scale 2-Storey Building With Fiber-Reinforced Elastomeric Isolators

Abstract

During the last two decades fiber-reinforced elastomeric isolators (FREIs) emerged as a promising option to reduce both the cost and weight of rubber bearings. The project ERIES-FREISUST (Fiber-Reinforced Elas-tomeric Isolators for seismic resilient structures with SUSTainable Solu-tions) aims to demonstrate the reliability of FREIs in limiting damage to structural and nonstructural components and contents. Two FREI systems were designed for a full-scale 2-story reinforced concrete (RC) infilled frame, differing in standardization and cost levels, namely a Virgin-rubber Carbon-fiber FREI (VC-FREI) and a Reclaimed-rubber Polyester-fiber FREI (RP-FREI). These isolation systems were installed in unbonded con-figuration at the base of the building and tested at the ST3D shaking table facility of Laboratorio Nacional de Engenharia Civil (LNEC), Lisbon, Por-tugal. The novel base-isolation systems demonstrated lateral stability and re-centering capability, as well as adequate vertical stiffness and load-bearing capacity under different ground motions. RP-FREIs were designed and tested up to a design displacement of 105mm corresponding to 150% shear strain. Due to recessing plates VC-FREIs were tested with higher scaling factors compared to RP-FREIs showing higher displacement capaci-ty with negligible residual. The building had no minor damage after the whole testing sequence with contents undergoing limited accelerations and displacements thus ensuring functionality even after major earthquakes.