斜风作用下桥塔施工阶段抖振性能

为了研究不同风速、风偏角在施工阶段对桥塔抖振性能的影响,进行了考虑塔吊共同作用的桥塔联合气弹模型风洞试验。试验结果显示:桥塔的抖振位移响应可近似地表示为风速的二次函数,桥塔抖振响应随着风偏角的增加呈非单调变化,施工状态中桥塔顺桥向和横桥向抖振位移响应最大值会出现在非正交风作用下;在施工阶段设计风速下抖振位移响应最大值为0.2746m,在工程可接受范围内,试验得出的抖振位移响应均方根值显著大于抖振时域分析计算值,说明桥塔风洞试验应考虑施工状态和施工机械对其抖振性能的影响。

Buffeting performance of bridge tower under yawed wind during construction

In order to study the influences of different wind speeds and wind yawed angles on the buffeting performance of bridge tower during construction,a wind tunnel test of bridge tower aeroelastic model was made based on considering the action of tower crane.Test result shows that the buffeting displacement responses increase with the increase of wind speed,have a trend of conic curve approximately,the buffeting responses of bridge tower with the increase wind yawed angle is not monotonous,the longitudinal and lateral buffeting responses of bridge tower can reach their maximal values under non-cross wind attack;the maximal value during construction is 0.274 6 m under design wind speed,which is acceptable to the project,the test result of RMS(root mean square)is significantly greater than the analysis result in time domain,so buffeting analysis should consider the influence of construction stages and machineries in wind tunnel test.2 tabs,9 figs,11 refs.