苏通大桥静风响应分析

给出了大跨度缆索承重桥梁静风响应的分析步骤;全面研究了苏通大桥在静风作用下,桩基础刚度、拉索分段、风速剖面、主梁初始攻角和附加攻角等对主梁和桥塔静风位移、静风失稳风速及结构振动频率的影响,并与风洞试验结果进行对比分析。结果表明:静风位移计算值低于风洞试验实测值,雷诺数是其主要原因;如果不考虑桩基础刚度影响,结构侧向位移响应会被严重低估;斜拉索横向风荷载在总体风荷载中所占比例超过40%;不考虑主梁附加攻角会高估静风失稳风速约20%;静风作用下一阶对称竖弯、侧弯和扭转模态频率计算结果与全桥气弹模型风洞试验结果特点相似。

AEROSTATIC RESPONSE ANALYSIS ON SUTONG BRIDGE

The analytical procedure for analyzing the large-span cable-supported bridge aerostatic response is presented.The influence of the pile foundation rigidity,cable segmentations,wind profiles,deck initial and added attack angles on deck displacements,pylon displacements,aerostatic divergence wind velocities and mode frequencies are comprehensively investigated.The calculated results are compared with those measurements in wind tunnel tests.The computational aerostatic displacement is less than the experimental values in the wind tunnel test.If the foundation rigidity effect is not taken into account,the lateral displacement will be severely underestimated.Among the total wind loads on structure,the contribution of cables exceeds 40%.The aerostatic divergence wind velocity will be overestimated by 20% if the added attack angle of the deck is omitted.The numerical characteristics of the first symmetric vertical,lateral bending and torsional mode frequencies are similar to the results acquired in the wind tunnel test of the aeroelastic full bridge model.