碳纤维缆索悬索桥竖向非线性自由振动研究

VERTICAL NONLINEAR FREE VIBRATION OF SUSPENSION BRIDGES USING CARBON FIBER CABLES

在把碳纤维缆索悬索桥与钢缆索悬索桥比较的基础上,研究了悬索桥的竖向非线性自振问题,利用Galerk in原理及L-P法求出了悬索桥竖向非线性自振的近似解,讨论分析了温度、振幅等因素对悬索桥竖向非线性自振的影响.得到了温度升高使悬索桥非线性自振频率降低,且对钢缆索悬索桥振动时程曲线影响较大,而温度变化对碳纤维缆索悬索桥振动时程曲线几乎无影响,振幅增大将使悬索桥非线性自振频率增大的结论.

On the basis of comparing the suspension bridges using carbon fiber cables with those bridges using steel cables, the vertical nonlinear vibration feature of suspension bridges was studied, the approximate solutions of suspension bridges＇ vertical nonlinear vibration were obtained with Galerkin principle and L-P method, and the impact of temperature, amplitude and other factors on the vertical nonlinear vibration of suspension bridges was analyzed. The temperature increment will make the nonlinear vibration frequency of suspension bridges fall, and have larger impact on the time-histories curve of suspension bridges using steel cables. On the contrary, temperature change nearly hasn＇ t any impact on the time-histories curve of suspension bridges using carbon fiber cables, and amplitude increment will make the nonlinear vibration frequency of suspension bridges increase.