BEHAVIOUR OF HIGH PERFORMANCE CONCRETE JOINTS ANALYSIS BY MATHEMATICAL MODELLING WITH MATLAB
High Performance Concrete (HPC) and its improved derivatives, Steel Fibre Reinforced High Performance Concrete (SFRHPC) and confined Ultra-High-Performance Concrete (UHPC), are being used more often in the beam-column joints of reinforced concrete (RC) frames due to their superior compressive strength, dense microstructure, and enhanced seismic resistance when compared to Normal Concrete (NC). Synthesized evidence reveals an important subtlety in structural response: while strength and stiffness gains scale directly with concrete compressive grade, ductility does not always increase and can deteriorate into brittle failure in the absence of explicit transverse confinement or fiber reinforcement. This research provides an extensive assessment of the behavior of HPC beam-column joints using experimental, analytical, finite-element (FE), and machine-learning (ML) literature. It creates a thorough five-phase mathematical modeling framework that can be implemented in MATLAB. It incorporates data-driven cross-validation modules, closed-form axial-flexural capacity formulations, degrading hysteretic bond-slip joint models, and strain-energy minimization based on Menabrea's theorem for internal joint force redistribution. Every quantitative dataset used to calibrate the framework has undergone cross-verification with its original publications from open-access sources.