自锚式悬索桥横向粘滞阻尼参数的理论确定方法

某自锚式钢桁架悬索桥结构主跨408m,采用双层桥面,两根主缆为空间线形布置。根据自锚式悬索桥独特的动力特性,提出了在该悬索桥主梁与过渡墩、辅助墩之间沿横向设置粘滞阻尼器的消能减震设计方案,以控制悬索桥的横向地震反应。在粘滞阻尼器参数确定时,提出了速度指数确定的基本原则,并且根据虚功原理列出了主梁的横向振动方程,进而得出最优阻尼系数的确定方法;另外,将粘滞阻尼器与弹簧并联进行减震设计,可增加结构的早期刚度,并能获得较好的减震效果,可供工程实践参考。

Theoretical Determination of the Parameters of Transverse Viscous Damper along Self-Anchored Suspension Bridge

The self-anchored steel truss suspension bridge,with span of 408 m,floors of deck,has two main cables three-dimensionally distributed.Based on the particular dynamic characteristic of self-anchored suspension bridge,the viscous dampers are proposed to install between the deck and the anchor(auxiliary) piers to improve the transverse seismic response of the bridge structure.In the viscous damped energy-dissipated earthquake-reduction design scheme,the law how to choose damp exponent and how to choose optimal damp coefficient according to mechanical equation of the deck have been proposed.In addition,the results of analysis show that the initial stiffness of the structure can be enhanced and the transverse earthquake effect of the bridge can be reduced effectively by the simultaneous application of viscous damper and its shunt-wound spring,as can be used as reference for engineering practice.