Seismic Behavior Tests of Centrifugal Circular Hollow Segmental RC Column With Flange Connection

To solve the problems faced by the flange connection in the application of concrete piers, such as difficult connection implementation, indistinct force mechanism, and unclear seismic performance, this paper proposes a new flange connection-based centrifugal circular hollow segmental RC column-column node assembly scheme. Thus, the prefabricated assembly technology of the bridge substructure can be further improved. Based on the Jianli-Jiangling Expressway Honghu No. 1 Special Bridge project, a 5.6 m height 1∶1 full-scale model was designed and fabricated. Its seismic performance and failure modes were studied by conducting the quasi-static load test and numerical simulation analysis. Based on the yield line theory and T-node model, the force mechanism of plates and bolts in flange connection nodes was analyzed, and the calculation model of the bending resistance of flange connection nodes was established. Results show that when the flange node is set at the most unfavorable bearing position, which is the plastic hinge area at the bottom of the pier, the mechanical properties of flange-connected precast piers are close to those of conventional cast-in-place piers in the elastic phase and meet the seismic design requirements of low-intensity zones in the actual projects. However, the damage occurs at the flange node after the bridge pier yielded, which indicates that its energy dissipation capacity has some limitations. Therefore, further research is needed for the application in medium and high-intensity zones. The proposed node force model reasonably explains the cause of the damage. Accordingly, a design method for plate thickness and reinforcement diameter applicable to this flange connection node is proposed to provide design recommendations for future applications in medium and high-intensity zones.