大跨度斜拉桥非线性静风稳定分析

随着跨径不断增大,斜拉桥存在静风失稳的可能性。综合考虑了静风荷载和结构自身非线性因素的影响,引用大跨度桥梁非线性静风稳定分析理论,采用增量双重迭代搜索法对大跨度斜拉桥进行了非线性静风稳定分析。编制了相应程序应用于香港汀九桥这一结构形式独特新颖的大跨度斜拉桥,由其全过程力学行为探明了其静风失稳机理,并对其失稳过程中的一些特殊物理现象做出解释。最后,探讨了初始风攻角对汀九桥静风稳定性的影响。

NONLINEAR AEROSTATIC STABILITY ANALYSIS OF A LONG SPAN CABLE-STAYED BRIDGE

Aerostatic instability analysis is necessary for long span cable-stayed bridges. Considering the nonlinear effects of structure and static wind load, the nonlinear aerostatic stability theory for long span bridges is applied in this paper. The incremental double iteration method is used to analyze the nonlinear aerostatic stability for long span cable-stayed bridges. The corresponding program is developed and used to analyze the cable-stayed Ting Kau Bridge at Hong Kong with a new design idea. The mechanism of its aerostatic instability is discussed and the causes for some special physical phenomena are explored through a study of the full range mechanical characteristics of Ting Kau bridge. Finally, the effects of the initial angle of incidence and cable sag on aerostatic stability of Ting Kau Bridge are discussed.