Study For Technological Mechanics In Carbon Fiber Reinforced Polymers Repairing Structures

Structures strengthening and repairing is very important in civil engineering. As a new strengthening technique, structures' strengthens with Carbon Fiber Reinforced Polymers (CFRP) is a concern focus in the field of strengthening and repairing. In contrast to the traditional methods of repairing damaged structures, the use of CFRP composites has several advantages, such as without stress concentrations, no residual stress, easy to construct and low maintenance cost.This paper developed a program based on ANSYS software, which can simulate the whole repairing progress automatically, mainly including the establishment of finite element model, analysis of the repair effect, and the influencing factors of repair effectiveness.The typical problems of bonded composite repair and reinforcement of cracked structures are considered in this paper. First, the effective FEM models are established by developing supplementary code combined with ANSYS software. For further, the influence of technological parameters including properties of CFRP, geometry of CFRP and the properties of adhesive layer on the repair effectiveness are investigated according to the variation of the stress intensity factor at crack tip before and after repair. The influencing parameters on the stress intensity factors at crack front are discussed by systematically numerical simulation. The results showed that the stresses near the crack tip will increase under tensile loading along the crack orientation, but will decrease under pressure stresses, and the increase in the elastic modulus or the thickness ofCFRP can improve the effectiveness of strengthening significantly, as well as the increase in the shear modulus or the decrease in the thickness of adhesive layer.The authors are grateful to the support of Liaoning Province Education Department in China, Grant No.20060164.