交叉吊索对超大跨CFRP主缆悬索桥静风失稳的抑制作用

摘要

大跨度桥梁静风失稳有可能先于动力失稳，且破坏性更强，应予以重视。简单经济的交叉吊索可在基本不增加成本的前提下，有效改善超大跨悬索桥的静风稳定性。采用三维非线性分析方法，研究了交叉吊索对超大跨CFRP （Carbon Fibre Reinforced Plastic）主缆悬索桥静风抗力、失稳过程及失稳形态的影响。在提出有助于提高其静风稳定性的交叉吊索最优设置位置的同时，揭示超大跨悬索桥静风失稳机理，并就交叉吊索对静风失稳的抑制作用机理进行了深入研究。研究表明，交叉吊索能有效改善超大跨CFRP主缆悬索桥的静风失稳性能。%Aerostatic instability may occur before aerodynamic instability in a large-span bridge and it is more destructive.So it should receive more attention.The aerostatic stability of a super large-span suspension bridge can be significantly improved using crossed hangers after the completion of the whole bridge with a very low cost.Here,the 3D nonlinear finite element method was used to analyze the effects of crossed hangers on aerostatic stiffness,aerostatic instability process and instable configuration of a super large-span suspension bridge with carbon fibre reinforced plastic (CFRP)cables.The best locations of crossed hangers to improve the aerostatic stability of the suspension bridge were proposed and the aerostatic instability mechanism of the bridge was studied.The improvement principle of crossed hangers was studied deeply.The study results showed that the aerostatic stability of a super large-span suspension bridge is significantly improved with crossed hangers.