提高CFRP缆索悬索桥抗风稳定性的结构措施研究  

Study of Structural Measures for Improving Wind Resistance Stability of Long Span Suspension Bridge with CFRP Cables

作　　者：梅葵花[1] 毕银博[1] 张浩[1] 

机构地区：[1]长安大学桥梁与隧道陕西省重点实验室,陕西西安710064

出　　处：《桥梁建设》2011年第5期26-30,共5页Bridge Construction

基　　金：国家自然科学基金项目(50908016)

摘　　要：为研究大跨度CFRP缆索悬索桥在设计风速下的抗风稳定性,对抗风设计规范中临界风速和颤振稳定系数计算公式进行整理,发现提高悬索桥的竖向弯曲基频和扭转基频可以提高桥梁的抗风稳定性。以日本明石海峡大桥为背景探索性设计了主跨2 000m的CFRP缆索悬索桥和钢缆索悬索桥,分别计算了采用2种材料、3种吊索方案(交叉吊索、空间缆索、索桁)的不同桥梁的动力特性。经对比分析得出以下结论:综合交叉索方案可以显著提高对称和反对称扭转振动频率;空间缆索方案扭转频率提高不显著且施工困难;索桁方案各个方向振动频率均得到提高,但材料用量大,施工工艺复杂;采用CFRP缆索有利于提高悬索桥的抗风稳定性。To study the wind resistance stability of long span suspension bridge used with CFRP cables under the designed wind speed,the calculation formulas related to the critical wind speed and flutter stability coefficients in the wind resistance design codes are sorted out and it is found that the improving of vertical bending and torsion base frequencies of suspension bridge can improve the wind resistance stability of the bridge.With reference to the Akashi-Kaikyo Bridge,Japan,the design of the CFRP cable and steel cable suspension bridges each with a main span of 2 000 m is studied.The dynamic characteristics of different bridges used with two kinds of the materials and three kinds of suspenders（crisscross suspenders,spatial cables and cables and truss） are respectively calculated.The conclusions drawn from the comparative analysis are that the crisscross suspenders can significantly improve the symmetric and asymmetric torsional vibration frequencies.The improving of the torsional vibration frequencies by the spatial cables is not significant and the construction is difficult.The vibration frequencies of the cables and truss in all directions are improved,but the usage amount of materials is great and the construction technology is complicated.The utilization of the CFRP cables for long span suspension bridge is nevertheless helpful to improve the wind resistance stability of the bridge.

关 键 词：悬索桥 抗风稳定性 有限元法 CFRP缆索 动力特性 

分 类 号：U448.25[建筑科学—桥梁与隧道工程]