Bidirectional shaking table tests of a low‐cost friction sliding system with flat‐inclined surfaces

Abstract

A novel low-cost friction sliding system for bidirectional excitation is developed to improve the seismic performance of reinforced concrete (RC) bridge piers. The sliding system is a spherical prototype developed by combining a central flat surface with an inclined spherical segment, characterized by stable oscillation and a large reduction in response accelerations on the flat surface. The inclined part provides a restoring force that limits the residual displacements of the system. Conventional steel and concrete are employed to construct a flat-inclined spherical surface atop an RC pier. The seismic forces are dissipated through the frictions generated during the sliding movements; hence, the seismic resilience of bridges can be ensured with a low-cost design solution. The proposed system is fabricated utilizing a mold created by a threedimensional printer, which facilitates the use of conventional concrete to construct spherical shapes. The concrete surface is lubricated with a resin material to prevent abrasion from multiple input ground motions. To demonstrate the effectiveness of the system, bidirectional shaking table tests are conducted in the longitudinal and transverse directions of a scaled bridge model. The effect of the inclination angle and the flat surface size is investigated. The results demonstrate a large decrease in response acceleration when the system exhibits circular sliding displacement. Furthermore, the inclination angle that generates the smallest residual displacement is identified experimentally. K E Y W O R D S3D printer, bidirectional motion, friction sliding system, RC bridge pier, seismic resilience

Development of a bidirectional rocking isolation bearing system (Bi‐RIBS) to control excessive seismic response of bridge structures

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Experimental Parametric Study and Phenomenological Modeling of a Deformable Rolling Seismic Isolator

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Shake-Table Testing of Low-Cost, High-Performance Seismic Isolators Based on Rolling Rubber Spheres

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