拉索动力特性实用计算方法

Practical Calculation Method of Stay Cable Dynamic Property

拉索是斜拉桥中必不可少的一部分,它充分利用了其较高的抗拉强度,使得结构合理、轻巧、美观。拉索的动力特性是分析拉索性能的基础。拉索的振型可分为索面外振动、索面内反对称与对称振动3种形式,文中总结了拉索这3种振型的动力特性的解析解。由于拉索面内对称振动频率解析解的复杂性,文中还就该频率方程解析解的特点,给出了便于工程计算的近似解,并对实际斜拉桥的拉索进行了动力特性计算,分析确定该近似解的精度以满足工程计算的要求。

The stay cable dynamic property is the base of performance analysis of stay cable in stay-cable bridges. The vibration mode shapes of cable could be divided into three kinds： vibration out of the cable plane, anti-symmetric vibration in plane and symmetric vibration in plane. In this paper, the analytic solutions of cable dynamic property in these mode shapes were summarized. Owing to the complexity of the analytic solutions in symmetric vibration, and according to the characteristic of those analytic solutions, the approximate solutions were presented for engineering calculation. At the end, an example of real stay cable was calculated, and the precision of that approximate solution was analysed.