Study on buffeting performance of double cantilevers of П type beam cable-stayed bridge under oblique wind

Abstract

Based on the aeroelastic model experiment of a long-span cable-stayed bridge, the vertical and torsional buffeting responses of π beam under different wind deflection angles are studied, and the influence of wind attack angle on buffeting response is further studied. The results show that the vertical and torsional buffeting displacement responses of the main girder increase in quadratic function with the wind speed. Moreover, the maximum value of buffeting response is not at the 0° wind deflection angle, and the position of the most unfavorable buffeting response is different under different attack angles. With the increase of wind deflection angle, the vertical and torsional buffeting displacement response of π type girder generally decreases first and then increases, then decreases and then increases, presenting the phenomenon of “three twists and turns”. The increase of wind deflection angle to buffeting response is generally between 10% and 20%, and the maximum can reach 40%. The comparison between the test results and the analysis results shows that the influence of the oblique wind effect and the wind attack angle on the buffeting response must be considered when analyzing the buffeting response of the cable-stayed bridge.