Investigation on the integrated transfer function characteristics for the buffeting response prediction of elongated structures

Previous studies have shown that the integrated transfer function (ITF) is independent of turbulence characteristics and can be effectively applied to predict the buffeting response of elongated structures, assuming that the strip hypothesis is valid. However, existing research has not effectively identified the ITF through segment model vibration tests, and the influence of the 3D effect on the accuracy of the strip hypothesis and the characteristics of the ITF in wind tunnel tests has not been quantitatively studied. A segment model vibration measurement device that can change a test model's span-width ratio was designed in this study. An airfoil section and a streamlined box girder section structure were taken as the background, and their ITFs were effectively identified under different L/B (L denotes the turbulent integral scale and B denotes the structural width) and model span-width ratios. The influence laws of the 3D effect on the accuracy of the strip hypothesis and ITF identification in wind tunnel tests were systematically investigated. The results showed that L/B and the structural span-width ratio are two significant controlling factors that affect the accuracy of the strip hypothesis and ITF identification. The research provides an effective experimental method for accurately predicting the buffeting response of elongated structures based on ITFs identified through segment model vibration tests.