考虑拉索的垂度、大位移引起的几何非线性及空气动力对系统的影响,将桥面简化为等截面的连续梁,建立了索.桥耦合的非线性振动模型。得到了对不同拉索数值求解的结果,表明当桥面和拉索的振动频率比值在1:1和2:1附近的小区间范围内时,索-桥耦合系统将产生严重的内共振,并呈现拍振的特征,而拉索与桥面耦合的振动特性与索的振动频率、垂度、倾角、风速偏航角、风速大小和阻尼等因素有关,从而为桥梁的设计和计算提供了理论依据。
The nonlinear coupled vibration model of cables and bridge decks is established. The decks are simplified as continuous beams with uniform cross section. The sag of cable, aerodynamics and geometric non-linearity caused by large displacement are considered. The numerical results of different cables are obtained. Serious internal resonance with beat rhythm can occur when the ratio of cable frequency and deck frequency is close to 1:1 and 2:1. The results show that the vibration characteristic of the coupled system is related with the sag of cable, vibration frequency, wind velocity, yaw angle of wind velocity, inclined angle and damping. It can provide theoretical basis for bridge design and calculation.