ENERGY RELEASE RATE OF STEEL PLATES BONDED BY CFRP WITH JOINT AND STEP

Abstract

 A carbon fiber reinforced polymer (CFRP) has begun to be applied to the deteriorated steel structures. In the debonding prevention design method in “Guidelines for Repair and Strengthening of Structures using Externally Bonded FRP”, an energy release rate is employed for the strength of the bonded joint where the required FRP bond length is sufficient.

 The length of the highly-elastic type of CFRP plates or CFRP strand sheets may be restricted by transportation and construction. In this case, it should be done the debonding prevention design at the joints between CFRP plates and design of required bond length of patch CFRP. In this paper, under the conditions of uniaxial force and pure bending, the energy release rate on the joint and on step ends of CFRP bonded on steel plates were given. Additionally, the simple equations of energy release rates were verified by the FEM results.