Seismic behavior of self-centering precast segmental bridge piers with external auxetic steel shear panel dampers

Precast self-centering segmental bridge piers have gained significant attention in bridge construction. Among them, development of the energy dissipation devices that are applicable for the self-centering bridge piers has been a major focus over the past three decades. This study develops a novel post-tensioned precast segmental bridge piers (SC-PSBPs), incorporating replaceable external auxetic steel shear panel dampers (ASSPDs) at the bottom and connecting steel plates at the intermediate segments. The seismic behavior of the SC-PSBPs is investigated through experiments and numerical simulations. Auxetic metamaterials are utilized to develop two kinds of perforated steel plates, including elliptical and peanut-shaped perforations, for the ASSPDs. Eight SC-PSBP specimens are tested to study failure patterns, hysteresis response, residual displacement, segment gap opening behavior, and local response of steel components. Test results show that the proposed SC-PSBP, equipped with unbonded post-tensioning (PT) tendons and ASSPDs, exhibits stable hysteresis response and self-centering capacity with minimal concrete damage. Plastic deformation is concentrated in the ASSPDs, while the intermediate connecting steel plates behave elastically throughout the loading history. A numerical model is developed to investigate the influence of design parameters on the hysteresis behavior of SC-PSBPs. Parametric analyses using the validated FE models explore the seismic behavior of SC-PSBPs with different geometries of ASSPDs, connecting steel plates, and initial PT forces. Numerical results show that both the ASSPDs and the connecting steel plates are imperative to achieve the desired rocking and damage concentration mechanisms of SC-PSBPs. The numerical findings also indicate that decreasing the porosity of ASSPDs effectively enhances the bearing and energy dissipation capacity of SC-PSBPs, as well as increases their residual displacement.