中文摘要：

大跨度桥梁涡激振动振幅的判定,采用大尺度主梁节段模型风洞试验可得到更精细的结果。为分析模型尺度对试验结果的影响,通过对南京长江四桥主梁1∶50和1∶20两种几何尺度扁平箱梁节段模型的涡振试验,对比两者在涡振振幅、涡振风速、涡振区、St等方面的差异,并结合雷诺数效应、阻尼比、模型细部模拟等影响因素进行分析。得知模型几何尺度越大,Re和St越大,CD越小,涡振振幅越小;常规尺度模型细部模拟的误差可能会显著影响涡振振幅;Sc增大时,锁定状态下结构振幅减小,涡振区也随之变窄,但Sc增大并不改变St数。

英文摘要：

For judgment of the amplitude of the vortex-induced vibration of long span bridge,the wind tunnel tests using the large geometry scale sectional model for main girder of the bridge can achieve more refined results.To analyze the influence of the model scale on the test results,the vortex-induced vibration tests were made for the two kinds of the geometry scale sectional models(1∶50 and 1∶20) of the flat box girder for main girder of the Forth Nanjing Changjiang River Bridge and the differences of the two ki...