Cyclic Load Tests on Precast Segmental Bridge Columns with Both Steel and Basalt FRP Reinforcement

Abstract

This paper presents an experimental investigation of a novel precast segmental bridge column (PSBC) that is longitudinally reinforced with both fiber-reinforced polymer (FRP) bars and conventional steel bars. The major objectives of this study were (1) to compare the seismic performance of FRP-steel–reinforced PSBCs (FSR-PSBCs) with the conventional steel-reinforced PSBC (SR-PSBC) members; and (2) to investigate the effects of the proportion of FRP to steel reinforcement and the gravity load level on the cyclic behavior of the FSR-PSBC. To this end, quasi-static tests were conducted on four large-scale PSBC specimens with heights of 4.2 m and cross sections of 0.6×0.4 m. Basalt FRP (BFRP) bars were employed in the FSR-PSBC specimens. Test results showed that as compared with the SR-PSBC, FSR-PSBC specimens exhibited appreciably improved self-centering capacities, postyield stiffness ratios, displacement ductility, and comparable hysteretic energy dissipation abilities. Furthermore, after the FSR-PSBC specimens were cyclically loaded up to a drift ratio of 5.5%, the damages were insignificant and could be repaired rapidly, indicating promising post-earthquake serviceability of these bridge columns.