3D Shaking Table Tests of a Full Scale 2-Storey Building with Fiber-Reinforced Elastomeric Isolators

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 Elastomeric Isolators for seismic resilient structures with SUSTainable Solutions) 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 configuration at the base of the building and tested at the ST3D shaking table facility of Laboratorio Nacional de Engenharia Civil (LNEC), Lisbon, Portugal. 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 capacity 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.