Enhancing Seismic Performance of Reinforced Concrete Exterior Joints with Ultra-high-performance Steel Fiber Reinforced Concrete: A Parametric Finite Element Study

Beam-column joints are vital to the stability and performance of reinforced concrete (RC) frame structures, particularly under seismic conditions. Understanding their stress-strain behavior is crucial for evaluating their capacity and ductility. However, performing detailed experimental studies with numerous specimens is often impractical due to significant costs and time constraints. As a result, finite element (FE) analysis, supported by tools like ABAQUS, has become a preferred approach for studying joint behavior effectively. This study employs the finite element method (FEM) to analyze exterior beam-column joints designed for high ductility (DCH) and enhanced with ultra-high-performance steel fiber reinforced concrete (UHPSFRC). The FE results are validated against experimental data through comparisons of load-displacement responses, failure patterns, and reinforcement strain progression. Furthermore, the research examines the effects of parameters like UHPSFRC strengthening length, axial column load, and steel fiber content on joint tensile stress, providing insights into optimizing seismic performance.