Three-dimensional (3-D) aeroelastic effect is known as the main factor that leads to the discrepancy between the critical flutter states predicted by two-dimensional (2-D) deck section and 3-D full structure. The 3-D aeroelastic effect on flutter performance of long-span bridges was investigated through historical experimental data statistics, numerical flutter analysis and wind tunnel tests. The critical flutter wind speeds of 16 long-span bridges were statistically analyzed. Subsequently, numerical flutter analysis were conducted towards a 300m-span quasi-simply supported beam bridge, and the 3-D structural effect and the effect of additional static wind angle of attack were analyzed. Corresponding section and full aeroelastic model tests were both carried out for further investigation of 3-D aeroelastic effect. Real-bridge experimental results show that the 3-D aeroelastic effect may lead to a maximum relative deviation in critical flutter wind speed of more than ±30%. Numerical-analysis-based 3-D aeroelastic effect with the contribution of both the 3-D structural effect and the effect of additional static wind angle of attack presents positive but weak influence, while the test results present more significant 3-D aeroelastic effect. Some potential factors, such as the spatial correlation and amplitude-dependency of aerodynamic forces, may also play an important role in 3-D aeroelastic effect.

众所周知，三维（3-D）气动弹性效应是导致二维（2-D）甲板截面所预测的临界颤振状态与3-D完整结构之间差异的主要因素。通过历史实验数据统计，数值颤振分析和风洞试验研究了3-D气动弹性对大跨度桥梁颤振性能的影响。对16座大跨度桥梁的临界颤振风速进行了统计分析。随后，对300m跨准简支梁桥进行了数值颤振分析，并分析了3D结构效应和附加的静态风迎角效应。进行了相应的截面和完整的气动弹性模型测试，以进一步研究3-D气动弹性效应。实桥实验结果表明，3-D气动弹性效应可能导致临界颤振风速的最大相对偏差超过±30％。基于数值分析的3-D气动弹性效应同时具有3-D结构效应和附加静态风迎角的影响，呈现出积极但微弱的影响，而测试结果则显示出更显着的3-D气动弹性效应。一些潜在因素，例如空气动力的空间相关性和幅度依赖性，也可能在3-D空气弹性效应中起重要作用。基于数值分析的3-D气动弹性效应同时具有3-D结构效应和附加静态风迎角的影响，呈现出积极但微弱的影响，而测试结果则显示出更显着的3-D气动弹性效应。一些潜在因素，例如空气动力的空间相关性和幅度依赖性，也可能在3-D空气弹性效应中起重要作用。基于数值分析的3-D气动弹性效应同时具有3-D结构效应和附加静态风迎角的影响，呈现出积极但微弱的影响，而测试结果则显示出更显着的3-D气动弹性效应。一些潜在因素，例如空气动力的空间相关性和幅度依赖性，也可能在3-D空气弹性效应中起重要作用。