An emulative cast-in-place monolithic bridge column assembled with precast segments and UHPC materials

In order to improve the applicability of precast bridge columns in high intensity zones, a precast segmental column, equivalent to the cast-in-place(CIP) column was proposed, in which the ultra-high-perfornce concrete (UHPC) was used to connect precast column components. Two 1/4-scale precast segmental bridge columns assembled with UHPC and one monolithic CIP circular column with the same dimensions were designed and tested by applying cyclic quasi-static loading. Test and analysis results show that the UHPC-connected precast columns have the same typical characteristics as a conventional monolithic CIP column with respect to plastic hinge forming mechanism, failure mode, hysteretic behavior and energy dissipation capacity. There were no noteworthy cracks and damages observed around the UHPC connection areas, which may validate that the CIP column components can be firmly and reliably connected using UHPC due to its remarkable bond and confinement performance. Finally, a set of key parameters included by the Bouc-Wen-Baber-Noori (BWBN) model were identified based on the data recorded in the test. By means of the established BWBN model, the cyclic loading responses were recalculated, which matched well those from the test. This model can be further used for the seismic time- history analysis of bridge structural systems that include the UHPC connected precast columns proposed in this paper.