斜拉桥拉索参数振动的研究

为探讨桥面激励对斜拉索非线性的影响,研究了斜拉桥中拉索的参数振动,得出了拉索与全桥振动的频率匹配关系,并指出了抑制拉索参数振动的有效措施。结果表明,增大阻尼比并不能有效地抑制拉索的参数振动,但当阻尼比大于某一值时,拉索将不会发生参数振动;激励幅值越大,拉索发生参数振动时瞬态振幅和稳态振幅也越大,当激励幅值小于某一值时,拉索不会发生参数振动;为了抑制拉索的参数振动,可以通过拉索的阻尼比及拉索的激励幅值来综合控制。

Studies on Parametric Oscillation of the Stay Cables of Cable-stayed Bridge

To explore the impact of nonlinear ofthe stay cable under the excitation of thecable-stayed bridge, parametric oscillation in thestay cables is examined.The matching relationbetween the cables and the vibration frequencies ofthe bridge is given.And the effective measureswhich inhibit the parametric oscillation are indicated.The result shows that the parametric oscillation cannot be inhibited effectively when increasing thedamping ratio.When the damping ratio is over acertain value, stay cable won't appear parametricoscillation.And with the increasing of the excitationamplitude, the transient amplitude and the steadyamplitude increase when the parametric oscillationhappens.When the excitation amplitude is under acertain value, stay cable won't appear parametricoscillation either.To inhibit the parametricoscillation, a comprehensive detection measureincluding damping ratio and excitation amplitude canbe adopted.