Comparative study of composite column behaviour under compressive load

This study investigates the performance of composite columns under compressive loads, specifically comparing reinforced concrete (RC) columns, concrete-filled steel tube (CFST) columns, CFRP-wrapped concrete columns, and hybrid composite columns. The study uses Finite Element Analysis (FEA) and experimental testing to examine the axial load-bearing capacity, failure modes, and efficiency of square and rectangular columns with various reinforcement strategies, such as angle and batten strengthening. The findings reveal significant improvements in load capacity, with hybrid composite columns (steel and CFRP) showing a 26.5% improvement and CFST columns showing a 23.2% increase over traditional RC columns. Square columns consistently outperformed rectangular columns, with CES composite columns showing a 5.33% increase in capacity for square columns. CFRP-wrapped concrete columns had a 19.8% higher load capacity than conventional RC columns. The study also clarifies the unique failure patterns connected to each column type. While concrete-filled steel tube columns buckled and carbon fibre-reinforced polymer-wrapped columns showed delamination at the concrete interface, reinforced concrete columns failed due to concrete crushing. Both materials worked together in hybrid columns to resist deformation, resulting in gradual failure. The results demonstrate the advantages of hybrid composite columns, particularly in terms of increased load capacity, resilience to failure, and durability. This study provides vital information for improving civil engineering column designs, opening the door for more robust and practical solutions in modern infrastructure, bridges, and high-rise buildings.