大跨度悬索桥静风稳定可靠性分析

基于一次二阶矩可靠度理论和非线性静风稳定性的分析方法,把静风失稳风速、基准风速及风速随机性修正系数作为随机变量,提出了大跨度桥梁静风稳定性可靠度分析方法.以某大跨度悬索桥为工程实例,对不同初始风攻角下的静风失稳进行了可靠性分析,并进一步作了静风失稳可靠度敏感性分析.结果表明：该桥基本上不会发生静风失稳,＋3°;初始攻角工况是该桥发生静风失稳的控制工况,静风失稳可靠度对静风失稳风速最敏感.

Reliability Analysis of Aerostatic Stability for Long Span Suspension Bridges

Based on the first order reliability theory and nonlinear aerostatic stability analysis method, an approach for reliability analysis of aerostatic stability is proposed, in which the critical wind velocity for the aerostatic instability, basic wind velocity and correction coefficient of wind velocity are random variable. Taking a long span suspension bridge as an example, the failure probability of aerostatic instability under different initial attack angles is calculated, and sensitivity analysis is also conducted to understand the influence of different random variable. The resuhs show that aerostatic instability will not occur and the case with an initial attack angle of 3 degree controls the aerostatic instability for this bridge, and the critical wind velocity of aerostatic instability is the most sensitive factor.