Combining the feature that railway self-centering bridge piers require a pedestal at the pier bottom due to the stringent lateral stiffness demand, a study on the mechanical behavior of railway self-centering bridge piers with an orderly sacrificial mechanism is conducted, in which unbonded energy-dissipating bars are arranged in the pedestal and unbonded prestressing tendons are arranged in the pier body. By discussing the influence of the configuration form of unbonded reinforcements on the seismic performance, a hybrid configuration form of reinforcements to enhance the seismic performance of self-centering piers is proposed. The analysis of the process of change in the mechanical behaviors of reinforcements under the action of lateral cyclic loads is carried out. The factors influencing the hysteresis characteristics of self-centering pier and relationship between the key seismic performance indicators were investigated. The results showed that the high-strength reinforcements are arranged in a single row, the sudden drop in loading capacity caused by reinforcements fracture can lead to the failure of bridge piers. Based on the limited strain variability of reinforcements with different grades, mixing low-grade steel bars(HRB400) with high-strength steel bars(HTRB630) in a staggered arrangement can achieve orderly sacrifice of different grades of reinforcements and the continuous regulation of the compression area of the pedestal, and improve the deformation and bearing capacity of the pier. The reinforcement ratio of prestressing reinforcements affects the post-yield stiffness and lateral strength of self-centering pier. Initial prestressing values, reinforcement ratios, and vertical axial forces affect lateral stiffness. The distance ratio of reinforcements affects the failure of displacement of piers. The three main seismic performance indicators of the self-centering piers have significant positive correlations, i.e., the load carrying capacity decreases, the energy dissipation capacity and the residual displacement also decrease, whereas the maximum displacement and the residual displacement do not show a positive correlation.
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