Axial Loading Tests and FEM Analysis of Slender Square Hollow Section (SHS) Stub Columns Strengthened with Carbon Fiber Reinforced Polymers

摘要

This paper presents the experimental and analytical results of axially loaded stub columns of slender steel hollow square section (SHS) strengthened with carbon fiber reinforced polymers (CFRP) sheets. The total eight specimens were fabricated and the main parameters were: width-thickness ratio (b/t), the number of CFRP ply, and the CFRP sheet orientation. From the tests, it was observed that two sides would typically buckle outward and the other two sides would buckle inward. A maximum increase of 33% was achieved in axial-load capacity when 3 layers of CFRP were used to wrap HSS columns of b/t=100 transversely. Also, stiffness and was compared between un-retrofitted specimens and retrofitted specimens. To extend and better understand the experimental work, a companion analytical study (FEM study) was conducted. The comparisons between experimental observations and computed results show that the analyses provided good correlation to actual behavior.