Seismic performance of precast segmental bridge columns repaired with CFRP wraps

Precast segmental bridge columns (PSBCs) have many advantages compared with monolithic bridge columns. However, PSBCs could be severely damaged during an earthquake due to their limited seismic capacity. Rapid repair of the PSBCs and the seismic behavior of the repaired PSBCs are critical to the post-earthquake recovery of bridges with such columns. In this study, an original PSBC specimen is designed, constructed, and tested under cyclic loading. After the cyclic test on the original specimen is carried out, carbon fiber reinforced polymer (CFRP) sheets and sticky steel glue are used to repair the damaged specimen. The repaired PSBC specimen is then tested under the same loading protocol as the original specimen to compare their cyclic performance. Test results show that the concrete damage of the repaired specimen is reduced compared to the original specimen, and the repaired column has a relatively larger energy dissipation and residual displacement than those of the original column. To leverage the test results, detailed three-dimensional finite element models are developed and calibrated with the results from the experiments. Closely replicating the test results, the validated finite element models are used to replace the lab experiments for the parametric modeling of the seismic performance of bridges with PSBCs while capturing effects of CFRP. Specifically, the influence of CFRP design variables, including the CFRP cross-sectional area ratio and the CFRP height ratio, on the seismic performance of the repaired PSBCs is evaluated by using the validated finite element model. It is found that the CFRP cross-sectional area ratio has little effect on the seismic capacity of the repaired PSBCs, and the repaired PSBC with a CFRP height ratio of 2.0 is the most suitable for the repaired PSBCs investigated in this study.