Analysis Of Anti-seismic Performance For Super Long-span Cable-stayed Bridge With CFRP Cables

CFRP is widely applied in engineering, such as reinforcement of bridges and maintenance of bridges and all kinds of civil engineering. In the design and construction of bridges, stay cables of long-span cable-stayed bridges are the main bearing members. With the increase of span, the length of stay cables rise with the square of the span of bridges. The self-weight is large if traditional wire cables are used. The gravity of stay cables accounted for a very large proportion in allowable stress. However, CFRP has great advantages because of its good performances, which can solve the problems of traditional wire cables’ corrosion degradation. In the meantime, the self-weight of superstructure is released, the span capacity and the bearing capacity of cable-stayed bridges is enhanced. At present, the theoretical research and practical application of cable-stayed bridges with CFRP cables, especially about seismic performance. Therefore, this paper focus on seismic performance of long-span cable-stayed bridges, the main research contents are as follows:1. The dynamic analysis of super long-span cable-stayed bridge with CFRP cables. Firstly, the research status of its dynamic analysis is reviewed. Then, the analysis theory and computing method of super long-span cable-stayed bridge with CFRP cables are explained. Finally, subspace iteration method is used to compare the dynamic characteristics of cable-stayed bridge with the main span of 1600 m, adopting CFRP cables and traditional cables individually.2. The seismic response of super long-span cable-stayed bridge with CFRP cables. Firstly, the research status of its seismic response theory is reviewed. Then, the key points of seismic resistance, the selection and input of earthquake wave are explained. Finally, the time history for seismic response of multi-objectives and peak values of response are compared for key sections with CFRP cables and traditional cables individually.3. The study of damping method for super long-span cable-stayed bridge with CFRP cables. The internal force and deformation at end section and middle section of mid-span and side-span, the deformation of column top and the internal force of column bottom are computed with bridges using fluid viscous damper and longitudinal elastic cables. The results of two damping methods of cable-stayed bridges with CFRP cables and traditional cables individually are compared and summarized.The results obtained from this article can provide theory basis and reference for future study of dynamic characteristics and seismic resistances of super long-span cable-stayed bridge with CFRP cables.