Seismic Performance of Precast Segmental CFST Bridge Piers with External Replaceable Energy Dissipation Devices

To meet the new requirements of bridge piers for rapid repair after earthquake and improve the suitability of precast segmental bridge piers in medium and high intensity areas, a precast segmental concrete filled steel tube (CFST) bridge pier with external replaceable energy dissipation devices was proposed. Based on the ABAQUS software, the analysis models of the post-tensioned prestressing precast segmental CFST piers with three segments were established. The seismic performance of the precast segmental CFST piers with the energy dissipation devices of three different control parameters (section contribution rate, slenderness ratio and arrangement) was analyzed under cyclic loading. The results show that the precast segmental CFST piers can be rapidly repaired by replacing energy dissipation devices and other measures due to the damage level of piers can be controlled by using external energy dissipation devices. Compared with the pier without energy dissipation device, the lateral strength, initial stiffness and energy dissipation capacity of the precast segmental CFST piers with external energy dissipation devices are increased 11%−88%, 2.86%−6.87% and 2.3 times−12.9 times, respectively. Meanwhile, to ensure the feasibility of repair after an earthquake, it is suggested that the section contribution rate of the external energy dissipation devices should not exceed 1.9%. Due to the small diameter of the energy dissipation bar on the middle joint which will cause the energy dissipation bar at pier bottom to not be fully utilized, it is suggested that the reduction factor of the energy dissipation devices along the pier height should not be less than 0.5. The change of slenderness ratio of energy dissipation bars has an effect on the lateral strength and ductility of the piers. With the decrease of the slenderness ratio, the energy dissipation capacity increases but the residual displacement of the piers also increases gradually. It is suggested that the slenderness ratio of energy dissipation bars should be greater than 4.5. © 2022 Science Press. All rights reserved.