CFRP与钢组合斜拉索斜拉桥方案研究

熊文^1,2, 肖汝诚²

1.东南大学交通学院桥梁工程系桥梁与隧道工程研究所;2.同济大学桥梁工程系



摘要:

针对现阶段斜拉索设计所面临的难题,提出了一种新型的基于碳纤维增强塑料(CFRP)与钢组合斜拉索的斜拉桥方案.该方案将CFRP斜拉索与传统钢斜拉索分别应用于斜拉桥恒载活载状态,发挥CFRP材料高强轻质,钢材料弹性模量大的优势而同时又弥补各自缺点.介绍了该组合方案的设计方法和关键力学参数,并利用参数分析给出推荐取值.通过构造和全桥研究可以得出:与全钢斜拉索斜拉桥相比,该组合斜拉索斜拉桥垂度效应小,自重轻;而与全CFRP斜拉索斜拉桥相比,其整体刚度大,价格便宜.从理论上证明了这种组合斜拉索的力学优势和替代传统钢斜拉索或全CFRP斜拉索应用在斜拉桥上的可行性.

关键词:  斜拉桥  组合斜拉索  CFRP斜拉索  设计方法  可行性研究

DOI：10.11918/j.issn.0367-6234.2011.04.024

分类号:U448.27

基金项目:国家高技术研究发展计划项目(2006AA11Z120)



Cable-stayed bridges with CFRP and steel composite stay cables

XIONG Wen^1,2, XIAO Ru-cheng²

1.Department of Bridge Engineering,Transportation College,Southeast University,210096 Nanjing,China;2.Department of Bridge Engineering,Tongji University,200092 Shanghai,China

Abstract:

To solve current design problems of long-span stay cables,this paper proposed a new design of cable-stayed bridges with carbon fiber reinforced polymer(CFRP) and steel composite stay cables.In this design,the CFRP stay cables with high strength-to-weight ratio are applied in the dead load condition,where the high strength of stay cables is needed;while the steel stay cables with high stiffness and low cost are applied in the live load condition,where the stiffness of entire bridge is concerned.The design strategies and key design parameters for the proposed cable-stayed bridges were determined and the appropriate values of key design parameters were also suggested based on a parametric study.By comparing,it can be concluded that the proposed composite cable-stayed bridges have less cable sag and lower self-weight than cable-stayed bridges with steel stay cables and meanwhile have more stiffness and lower cost than those with CFRP stay cables.It is proved in this study that the use of CFRP and steel composite stay cables in cable-stayed bridges is feasible and the proposed composite cable-stayed bridges could become an excellent alternative to cable-stayed bridges with steel or CFRP stay cables.

Key words:  cable-stayed bridges  composite stay cables  CFRP stay cables  design strategy  feasibility study