PREDICTIVE MODEL ON THE BEHAVIOUR OF REINFORCED RECTANGULAR COLUMNS FOR ANALYSIS AND DESIGN

This study focuses on predictive modeling of the behavior of reinforced rectangular concrete columns for analysis and design. A total of 198 experimental samples were analyzed, including both plain (PL) and reinforced concrete (RC) columns using concrete grades M15 and M20, and reinforcement sizes Y8 and Y12. All specimens were subjected to axial compression tests to evaluate their load-bearing capacities across a range of Length to Depth (L/D) ratios from 1 to 13. The results revealed a consistent inverse relationship between L/D ratio and axial load capacity in all configurations. As the L/D ratio increased, axial capacity decreased significantly by approximately 80% to 87%, demonstrating the dominant effect of slenderness on structural performance, regardless of material strength or reinforcement details. Statistical analysis indicated that reinforced columns, particularly those made with higher-grade concrete and larger reinforcement bars (e.g., RC-M20-Y12), exhibited higher average axial capacities and lower variability, confirming their enhanced stability. A linear regression model was developed to predict axial load as a function of L/D ratio, providing a practical and efficient tool for preliminary column design and structural safety evaluation. The model effectively captures the axial strength reduction trend associated with increasing slenderness, allowing engineers to estimate column behavior based on geometry and material properties. This predictive approach supports the development of safer, more reliable, and cost-effective designs in reinforced concrete structures.