Theoretical Analysis on Galloping Stability of Stay Cables with Iced Accretion
Li Shouying 1, 2, Huang Tao2
[1] Key Laboratory of Concrete and Prestressed Concrete Structures of Ministry of Education, Southeast University, Nanjing, China, 210096;[2] Wind Engineering Research Center, Hunan University, Changsha, China, 410082
Abstract：Galloping vibration may take place on stay cables with iced accretions, which would affect the safety of cable-stayed bridges. Firstly, wind tunnel tests are carried out to measure the mean aerodynamic force coefficients on six kinds of cable models with iced accretion. Then, equation of motion of the first mode is derived, and the galloping responses are obtained by solving the equation by Runge-Kutta method. Taking Yangpu Bridge in Hainan Province, China as engineering background, the galloping critical wind velocity are investigated in detail, as well as the effects of cable damping ratio and iced accretion length. The results show that the galloping critical wind velocities of the longest stay cable M18 at the mid-span of Yangpu Bridge are 10 to 15 m/s, which is far less than basic wind speeds. It means that this cable have the risk of galloping vibration. Moreover, the galloping critical wind velocity increases with the increase of the cable damping ratio and the iced accretion length.
2013, Vol. 32 
