大跨度碳纤维复合材料主缆悬索桥的抗风性能研究

为了探讨碳纤维复合材料缆索在大跨度悬索桥中应用的可能性，以主缆等轴向刚度为原则，拟定了一座主跨为1490m的碳纤维复合材料主缆悬索桥，并运用三维非线性计算理论进行了动力特性、静风和空气动力稳定性的分析．通过与同跨度钢主缆悬索桥的比较，讨论了不同主缆材料对大跨度悬索桥抗风性能的影响．分析结果表明大跨度悬索桥采用碳纤维复合材料主缆后：（1）结构的自振频率特别是扭转频率有显著的提高；（2）静风作用下结构变形增大，但其静风稳定性却与钢主缆悬索桥基本接近；（3）空气动力稳定性要比钢主缆悬索桥好．因此从抗风性能角度而言，大跨度悬索桥采用碳纤维复合材料主缆是可行的，但是主缆截面尺寸的确定应采用等轴向刚度为原则．

Wind resistance of long-span suspension bridges using carbon fiber reinforced polymer cables

To gain understanding of the applicability of carbon fiber reinforced polymer(CFRP) cable in long-span suspension bridges,a 1490 m suspension bridge using CFRP cables is established,in which the cable's section is determined by the equivalent axial stiffness,the dynamic behavior,the aerostatic and aerodynamic stability of the bridge are analyzed by 3D non-linear computation theory.By comparison with the bridge using steel cables,effect of different cable's material on the wind resistance is investigated analytically. As CFRP cables are used in long-span suspension bridges,the results show that(1) structural natural frequencies are all increased,and particularly the torsional frequency is remarkably increased;(2) under the static wind action,structural deformation is increased,however its aerostatic stability is basically the same as that of the bridge using steel cables;(3) its aerodynamic stability is superior to the bridge using steel cables.Therefore,as far as the wind resistance is considered,the use of CFRP cables in long-span suspension bridges is feasible,and the cable's section should be determined by the equivalent axial stiffness.