Manuscript title: Non-linear analysis for CFRP wrapped steel box sections under bi-axial load

Abstract

This study investigates the effect of bi-axial compressive loading on Hollow steel box columns (HSBC) and concrete-filled steel box columns (CFSBC) sections wrapped with low modulus CFRP. The CFSBC and HSBC sections are simulated in the finite element- software (ABAQUS) and validated using available experimental data. The bi-axial compressive loading is considered for various eccentricities i.e., eccentricity to depth ratio (e/D) ratio of 0 to 0. 32. The results suggest that for the CFRP wrapped HSBC sections at low eccentricity (e/D =0.08), the compact and non-compact sections are effective to carry higher load and slender section is effective for concentric loads; while in CFSBC, compact and non-compact sections are effective for eccentric (e/D= 0 to 0. 32) loads. Also, it is observed that the low modulus CFRP layer wrapped to the CFSBC section has no significant effect on strength. Additionally, an empirical relationship based on trend analysis has been proposed, which gives the load-carrying capacity of any section. For the CFSBC section, P-M interaction curves have been presented to validated the simulation results under biaxial condition.