海南大学学报(自然科学版中英文)

针对大跨度悬索桥吊杆的风致内共振问题，探索了高性能CFRP材料应用于悬索桥缆索系统后的风致响应减振效果.探索性地设计了主跨2 000 m且缆索材料各异的悬索桥模型，根据CFRP主缆、钢主缆、CFRP吊索和钢吊索4种基本构件组合成4种缆索承重方案，分析了4种缆索承重方案的自振特性，并进行脉动风场模拟，在此基础上引入时域抖振力模型后得到结构风致响应的数值模拟结果 .研究结果表明：采用钢主缆钢吊杆的情况下，许多长吊杆存在明显的共振现象；主缆材料不变，将吊索材料替换为CFRP后，共振现象完全消失；采用CFRP主缆与钢吊索组合时，共振现象仍然存在，且吊杆的共振程度与钢主缆钢吊索方案类似；采用CFRP主缆与CFRP吊杆方案时，吊杆共振现象消除，其响应幅值甚至小于主缆的激励源幅值. 4种方案的对比表明，主缆材料对共振响应的影响不明显，用CFRP材料提高吊杆的自振频率则是消除共振的关键.

In the report, aiming at the wind-induced internal resonances hangers at long-span suspension bridges, the vibration-reduction effects were investigated in terms of application of high-performance CFRP material to the cable-supporting system. A suspension bridge with a main span length of 2 000 m was designed tentatively. Four kinds of cable-supporting system were combined according to 4 basic components including CFRP main cable, steel cable, CFRP hanger, and steel hanger. The natural vibration characteristics were analyzed and the fluctuating wind fields are simulated. Based on these data, a time-domain buffeting model was introduced and the wind-induced structural responses were obtained via numerical simulations. The results showed that when the scheme of steel main cables and hangers was used, many long hangers experience obvious resonant responses. Keeping steel for main cables, all resonant responses disappear when steel hangers are replaced with CFRP ones. When the scheme of CFRP main cables and steel hangers is used, the resonant phenomena still exist, of which the characteristics are similar to those of the all-steel scheme. When the all-CFRP scheme are used, all resonant phenomena disappear, whose responses are even smaller than the source amplitudes passed from the main cables. The compare analysis results suggested that to eliminate the resonance, the key point is promoting the natural frequencies by applying CFRP material to the hangers, instead of to the main cables.