Experimental study of a scaled bridge model with a unidirectional rocking isolation bearing system (Uni‐RIBS) through shaking table tests

Abstract

AbstractThis study presents the experimental results on a scaled bridge model with a newly proposed unidirectional rocking isolation bearing system (referred to as Uni‐RIBS) on a shaking table. The bridge model features one superstructure girder and four bearings. The experimental input encompassed a variety of recorded, design, and harmonic ground motions, characterized by differing peak accelerations, with or without vertical components, and time‐scaled attributes. The superstructure girder's mass was altered for two conditions (full and half). The test results validate the rocking mechanism inherent in the Uni‐RIBS and demonstrate the analytical model's accuracy in predicting the system's dynamics, including its negative stiffness, mass‐independent, and energy dissipation characteristics during bearing rotation reversals. Additionally, this study examines the effectiveness of a simplified numerical model in varying complexities for predicting the seismic responses of the bridge model.