The Performance Research Of Stay Cable Strengthened With CFRP

With the development of transportation construction, cable-stayed bridge is more and more widely applied. In this paper, aimed at the disease of cables in cable-stayed bridge, carbon fiber reinforced cable design methods is proposed. Based on reading of so much relevant documents, static behavior of carbon fiber reinforced cable and the effect of carbon fiber reinforced cable on the dynamic characteristics of the structure have be show in this paper.Existing diseases of cables are summarized. Directing at the easily damaged section of cable, study on partial carbon fiber reinforcement of cable has been done. First, a finite element model of cable has been established, and the static performance of the composite cable has been analyzed. Two different type fiber cloth,4,8, and 12 layers, are used in the study to wrap the PES 7-139 steel tendon. After comparative analysis of the data, the conclusion can be drawn:The yield strengthen, tensile strength and the elastic modulus can be strengthened obviously.A cable which is reinforced in the 0.1 times length near the end connected with beam is modeled by the finite element program. Through the vibration analysis on the reinforced cable, it can be seen:the vibration frequency of the reinforced cable are increased, but lightly. High-order mode nature vibration frequency's increase is more obvious. Higher mode natural frequencies of a higher percentage increase. With the reinforcement of carbon fiber, cable fundamental frequency toward a favorable direction. Because of the reinforcement by the fiber cloth, cable's fundamental frequency changes towards the favorable derection.On the base of the above work, by modeling different structure system stayed-cable bridge, comparative analysis on the fiber reinforcement's effect to the whole bridge vibration characteristic has be done. The result of the analysis shows that partial reinforcement of cable has less effect to the nature vibration characteristic. The reinforcement of cable has different effect to stayed-bridge of different structure system, the effect on floating system and semi-floating stayed-cable bridge is obviously higher than it on the rigid system stayed-cable bridge. Partial reinforced cable effect on different order vibration mode of stayed-cable bridge in different degrees. The effect of vertical bending vibration mode of girders and towers are significantly, but the effect on the horizontal bending vibration mode is slightly.At the last, the lack of this paper is summarized and the future research work is conceived. On the next step, the research work should focus on the fatigue resistance and corrosion resistance of fiber cloth reinforced cable. It should make in-depth research on reinforcement method and the design of anchorage zone.