粉房湾长江大桥节段模型风洞试验

Wind Tunnel Test for Sectional Models of Fenfangwan Changjiang River Bridge

粉房湾长江大桥为双塔双索面半飘浮体系斜拉桥,为检验该桥在强风下的颤振稳定性及在常遇风速下的涡激振动性能,对该桥动力特性进行计算并按照1∶45.8的几何缩尺比制作6个标准主梁节段模型进行风洞试验,针对试验结果提出在主梁风嘴边桁处设置导流板的制振措施。计算和试验结果表明,该桥结构刚度大、振动频率高,在检验风速范围内不会发生颤振失稳和静风失稳,满足抗风设计要求;通过在主梁风嘴边桁处设置导流板,能够实现对桥梁涡激共振的有效控制,使其满足规范要求。

Fenfangwan Changjiang River Bridge is a semi-floating system cable-stayed bridge with double pylons and double cable planes.To verify the flutter stability of the bridge under the strong wind and the vortex-induced vibration performance under the common wind speed,the dynamic performance of the bridge was calculated and 6 models of the typical sections of the main girder were prepared according to the geometric scale ratio of 1∶45.8 for the wind tunnel test.In the light of the test,the vibration control measure of installing guide vanes on the wind fairing edge trusses of the main girder was proposed.The results of the calculation and test indicate that the structural stiffness of the bridge is great,the vibration frequency is high,the flutter instability and static wind instability will not occur within the range of the test wind speed and the bridge can meet the requirements of the wind resistance design.By way of installing the guide vanes on the wind fairing edge trusses,the vortex-induced resonance of the bridge can be effectively controlled and the resonance can be made to meet the relevant requirements in the codes.