Parametric Study on Behavior of Moment Resisting RCS Composite Joints

Reinforced Concrete Column and Steel Beam (RCS) systems have gained widespread popularity, particularly in seismic regions. This innovative structural system utilizes the intrinsic benefits of steel and concrete and presents a compelling alternative to traditional steel and RC construction. The primary challenge in this system is design, construction, and execution of an effective moment connection between the steel beams and RC columns. Several experimental studies have been conducted on various joint configurations to understand the connection behavior under reverse cyclic loadings. In this research finite element analysis was performed using ABAQUS to observe the failure modes and understand the load transfer mechanism of composite RCS joints with cover plate. Numerical models were developed and simulation results were validated against previously tested RCS beam-column subassembly. Concrete damage plasticity model was considered to incorporate the material nonlinearity of concrete. 3-dimensional 8-noded hexahedral brick elements was utilized for modelling concrete elements. Reinforcement was modelled using 2-noded truss elements and the embedded method with perfect bond between reinforcement and surrounding concrete was adopted to capture the interaction between reinforcement and concrete. Sensitivity analysis was carried out with parameters like., dilation angle, viscosity and mesh size. Thereafter, parametric study was conducted to assess the behavior and strength of the RCS joints having cover plate of different thickness and heights. In addition to that, the effect of column axial load and transverse beam on load-deformation curve, yielding of steel beam, and stress variation in cover plate of a joint was also recorded.