Experimental study on the seismic performance of precast and cast-in-place hollow circular piers under chloride-induced corrosion

Abstract

The seismic performance of five hollow circular piers with different corrosion ratios and connections is investigated by quasi-static tests in this work. The specimens can be divided into cast-in-place piers (CIP) and precast piers (PBP) connected by ducts. The electrochemical chloride erosion method was adopted to accelerate the speed of corrosion. The experimental results showed that the corrosion damage of PBP specimen was more severe than that of CIP specimen. The type of damage in the PBP specimens was of pitting corrosion, while uniform corrosion was observed in the CIP specimens, respectively. The closer to the interface between pier and footing, the more serious the corrosion of the longitudinal rebar in PBP specimens. However, the hysteretic performance and failure mode were similar between virgin CIP and PBP specimens. With the increasing corrosion ratio, all of the mechanical behaviors of corroded piers decreased significantly, especially in the peak load, energy dissipation, stiffness degradation, and residual displacement. Furthermore, a numerical model was established by OpenSees to predict the seismic performance of piers, and the bond-slip behavior of rebar and the hysteretic behavior of interface were considered in this model. For the corroded piers, the deterioration laws of materials were defined to simulate the influence of corrosion. The results showed that the proposed numerical method can effectively capture the performance of piers with different connection types and corrosion ratios.