Experimental study on exterior precast RC beam to CECFST column joint under lateral cyclic loading

• Main Author: Ho, Brandon Lye Kiat
• Other Authors: Tan Kang Hai
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Civil engineering::Structures and design
• Online Access: https://hdl.handle.net/10356/164010
• Institution: Nanyang Technological University

Beam-column joints (BCJ) play an integral role in the reinforced concrete (RC) frame structure. However, due to high seismic design requirements, there is high complexity in reinforcement detailing which results in congested reinforcement and difficulty in the prefabrication and construction process in regions with high earthquake intensity. This report is an experimental study on external precast (PC) reinforced concrete (RC) beam to concrete-encased concrete-filled steel tube (CECFST) column joints to evaluate their structural performance under seismic loading. In this study, we evaluate the influence of cast-in-situ concrete strength and axial loading on the structural joint performance. An experimental programme was conducted on four precast RC beam-to-CECFST column connections under lateral cyclic loading. The specimens were fabricated such that there were two groups of external joints with wet connections of different cast-in-situ concrete strength. Axial loading was then applied on one of the two specimens in each group during the cyclic tests. The test results including shear-force horizontal displacement hysteretic curves and envelop curves were presented. The displacement ductility coefficients, cumulative dissipated energy, equivalent damping coefficient, strength reduction and stiffness reduction were then calculated and analysed. In general, higher concrete strength and the presence of axial load improved the seismic performance of the specimens.