Effect of elevated temperature on bond behaviour of high modulus CFRP/steel double-strap joints

This paper investigates and provides experimental evidence of the bond characteristics between carbon fibre reinforced polymer (CFRP) and steel plates under elevated temperature exposures. A series of tensile tests was carried out on CFRP/steel plates specimens joined together in double-lap shear joints and subjected to a range of environmental temperatures between 20 °C up to 60 °C, which would be usually encountered in civil infrastructure applications. High modulus (640 GPa) unidirectional carbon fibre plies were used in wet lay-up fabrication method to strengthen the composite matrix. Three different epoxy resins were used for the fabrication of the CFRP/steel specimens. The objective of the current experimental work is to determine the ultimate strength, failure patterns, elongation development, and lap-shear stress and slip variation under those exposures. This will help in enhancing the competency of using CFRP in retrofitting steel structures at high-temperature environments, usually experienced in civil construction applications.