Numerical Simulation and Experimental Investigation on Seismic Performance of Composite Structural Connection of Encased CFST Column and Reinforced Concrete Beam with Steel Ring

Abstract

Introduction: This paper discusses the seismic characteristics of the composite structural joint between the Encased Concrete Filled Steel Tubular (ECFST) Column and Reinforced Concrete (RC) beam. The hysteresis behaviour, envelope curves, ductility, rigidity degradation, energy absorption capacity, and equivalent viscous damping coefficient are also discussed. Methods: In this study, the reinforcement placed longitudinally in the RC beam, which is disunited at the joint due to the tubular section of the ECFST column, is connected by providing links in the form of steel rings at the joint. In this study, four specimens with circular steel rings and square concrete casing along with two control specimens are considered. The number of ring layers and concentric rings are used in different combinations among the specimens. Results: The structural connection with the circular steel rings and square concrete casing at the ECFST column and RC beam joint showed superior seismic performance due to the provision of the longitudinal bar and the increased confinement at the joint due to the steel rings and additional concrete casing. Conclusion: A comparative study was done between the experimental studies and the numerical analysis from the finite element developed using ANSYS. It was found that the experimental investigation results matched with the finite element analysis.