大跨连续刚构桥最大悬臂阶段抖振时域分析

Time domain analysis of buffeting of long-span continuous rigid frame bridge at the longest cantilever stage

对某大跨连续刚构桥进行最大悬臂施工阶段的空间有限元分析,采用AR模型并考虑空间相关性对桥地址处脉动风场进行模拟。基于Miyata T准定常气动力模型,在ANSYS中引入自激力的影响,对该桥进行抖振时域分析,同时将结果与静阵风响应进行了比较,得到脉动增大系数,并利用抖振分析结果对该桥施工人员的安全性和舒适性进行了预评。

The spatial finite element analysis is made for a long-span continuous rigid frame bridge at the stage of its longest double cantilevers. Considering spatial correlation, the wind turbulence time histories of bridge site are generated by using Auto-Regressive model. Based on Miyata T quasi-steady aerodynamic model, and considering self-excited aerodynamic forces, the buffeting response of this bridge is analyzed at time domain, and the result is compared with the static gust response, then the fluctuating amplifying coefficients are obtained. In the end, the result of buffeting analysis is used to evaluate the security and comfort of the construction workers on this bridge.