Experimental study on seismic performance of precast segmental concrete columns after seawater freeze-thaw cycles

Abstract

To accelerate construction speed, precast segmental concrete bridge columns are widely used in offshore bridge construction. Due to the cyclic action of the tide and the difference of temperature between seawater and atmosphere, offshore piers inevitably experience seawater freeze–thaw cycles in cold climates. The purpose of this paper is to study the seismic performance of precast segmental concrete columns after seawater freeze–thaw cycles through experimentation. Based on the low cyclic loading test on 12 specimens with different freeze–thaw cycles, stirrup spacing values, axial compression ratios, and longitudinal reinforcement diameters, the seismic performance of precast segmental concrete columns was evaluated through analyzing cracking and failure patterns, hysteresis characteristics, skeleton curves, stiffness degeneration, and energy dissipation capacity. The experimental results reveal that, for the specimens with the same design parameters, increasing the number of freeze–thaw cycles from 0 to 125 gradually reduces the peak value of the lateral load, the initial stiffness, and the cumulative energy dissipation but continuously increases the peak displacement. Moreover, for the specimens experiencing 125 freeze–thaw cycles, longitudinal reinforcement diameter, axial compression ratio, and stirrup spacing are the main factors affecting the seismic performance of precast segmental concrete columns.