大跨柔性装饰拱顺风向抖振响应及疲劳性能研究

Along-wind buffeting response and fatigue performance research of long-spanned flexible decorative arch

由于大跨度柔性装饰拱的结构刚度低,风荷载作用下诱发结构抖振应力循环变化幅度大,相比普通桥梁形式更容易引起疲劳。以海南某大桥装饰拱结构为例,根据桥址的风速记录气象资料,统计常态风速的变化规律,利用时域分析的方法,基于风速数值模拟进行抖振时程分析获得不同风速下拱结构的应力时程,采取雨流循环计数法进行统计分析得出应力幅的概率分布规律,并联系年风速的统计变化规律采用Miner线性累积损伤理论对结构进行疲劳性能评价。

Because of the low structural rigidity of long-spanned decorative arch,wind-induced buffeting stress cycle amplitude varies largely,which can cause structure fatigue more easily than other ordinary bridges.This paper takes a long-spanned decorative arch in Hainan as example,counts the variation of the normal wind speed according to the wind speed meteorological data at the bridge located site,and obtains the stress time-history of the arch structure under different wind speed by using the time-domain method based on the numerical simulation of wind speed.And then using the rain-flow counting method,we can get the probability distribution law of circulating stress amplitude by statistic analysis,and evaluate the structure fatigue performance by contacting the regularities of distribution of wind speed,using Miner linear cumulative damage theory.