中央扣对大跨径自锚式悬索桥动力特性的影响

摘要

为了研究不同形式中央扣对大跨径自锚式悬索桥地震反应的影响，结合某主跨406 m 的自锚式悬索桥为工程实例，利用 Midas/Civil程序建立其未设中央扣、设置刚性和柔性中央扣的三种有限元模型，使用多重Ritz向量法分别得出三种模型前180阶自振频率及振型，分析对比中央扣对三种模型动力特性的影响。研究表明：中央扣的设置提高了自锚式悬索桥整体刚度；该自锚式悬索桥的竖弯刚度、主塔横向侧弯刚度都明显增大；设置刚性中央扣比柔性中央扣更能提高结构的刚度。%In order to study the effect of different forms of central buckle on the seismic response of long-span self-anchored suspension bridge,this article took a main cross-406 m of the self-anchored suspension bridge as the engineering example,used the Midas /Civil procedure to establish its three fi-nite element models of not set central buckle、set rigid and flexible central buckle,and used the multiple Ritz vector method to determine three models,first 180 natural frequencies and modes,then analyzed the influences on dynamic characteristics of the three models.The results show that the central buckle can im-prove overall stiffness of the self-anchored suspension bridge;the self-anchored suspension bridge,s verti-cal bending stiffness、lateral bending stiffness of the main tower are significantly increased;setting rigid central buckle is able to increase the stiffness of the structure more effective than flexible central buckle.