为研究两端水平激励作用下斜拉索面内非线性振动,利用Galerkin方法得到斜拉索的离散运动方程。利用多尺度法得到亚谐波共振和主共振时面内一阶振动幅值的表达式。由方程的推导过程可知:两端水平激励斜拉索在亚谐波共振时可等效为一端水平激励斜拉索,将上、下端激励幅值叠加后按一端激励计算;在主共振时则与一端水平激励有本质区别,不能按上述方式等效。算例分析结果较好地验证了该结论。
The discrete nonlinear governing equations are derived by using the Galerkin method to ascertain the effects of horizontal excitations on the in-plane nonlinear dynamic responses of stayed cables. The 1 st in-plane am- plitudes are solved by the method of multiple scales (MMS) in the sub-harmonic and primary resonances, respec- tively. For stayed cables, exciting at two anchorages or one anchorage is the same when only the sub-harmonic res- onance is considered. Thus, a stayed cable, which is excited at two anchorages, could be considered as one that is only excited at one anchorage by superposing the amplitudes of the upper and lower anchorage. However, this process is inapplicable, when the primary resonance is taking into account. Finally, this point of view is proved byan example.