EXPERIMENTAL STUDY ON STEEL CHS SLENDER COLUMNS STRENGTHENED BY CFRP UNDER AXIAL COMPRESSION

An experimental investigation was conducted on a steel circular hollow section (CHS) slender column and five steel CHS slender columns strengthened by CFRP under axial compression. The behaviour and failure modes of steel CHS slender columns strengthened by CFRP with different layers and reinforcing directions were studied. Furthermore, a finite element model composed of shells-spring-shells was developed using ANSYS. Based on the current British Code for Strengthening Metallic Structures using Externally Bonded Fibre-reinforced Polymers and Chinese Code for Design of Steel Structure, the design formulae are proposed in this paper for the stability capacity of steel CHS slender columns strengthened by CFRP under axial compression by introducing a correction factor (beta(c)). The stability capacity calculated using the proposed design formulae agreed well with the results obtained from the tests and finite element analysis, which indicates that the proposed design formulae are verified to be accurate. Therefore, the findings of this study provide support to the update of Chinese Code for Reinforcement Design of Steel Structures.