Study on Vortex-induced Vibration Performance of Hybrid Girder Railway Cable-stayed Bridge with Blunt Section

South Longxue Bridge is a hybrid girder cable-stayed bridge on the new Nansha Port Railway in Guangzhou. The bolt and welding combined technology with rectangular section is used in this bridge based on rapid construction technology. Wind resistance of the blunt section is one of the difficulties in design. Based on the project background of South Longxue Bridge, this paper studiedthe vortex vibration performance of railway hybrid girder cable-stayed bridge with blunt section. Multiple research methods were used in this study, such as the derivation of theoretical formula, CFD numerical simulation technology of hydrodynamics and section model wind tunnel test. The results of section model wind tunnel test show that at the angle of ±5°, ±3°and 0°, both large vertical bending vortex vibration and torsional vortex vibration will occur, which cannot meet the requirements and should be controlled with aerodynamic measures. A new aerodynamic measure was proposed using 1/4 stabilizer plate +15°baffle plate, which can effectively suppress the amplitude of vortex induced vibration within the allowable range. © 2021, Department of Journal of the China Railway Society. All right reserved.