不同水深条件下的带式浮桥水弹性特性

为了研究不同水深条件下的带式浮桥在移动荷载作用下的水弹性动力特性,采用基于梁式理论的解析模型和基于势流理论的边界元法模型。流体动力的影响利用基于势流理论的边界元方法来计算。将附加质量和阻尼系数分别与浮桥的质量和阻尼合并,恢复力与移动荷载合并,便可容易导出浮桥的振动微分方程。利用假设模态法,得出了水弹性固有频率及其动力响应的计算公式。结果表明,水深对浮桥的水弹性固有频率以及动力响应的影响不大,因此带式浮桥的设计和应用不必考虑水深的影响。

Hydroelastic behaviors of a ribbon pontoon bridge with different water depths

There are two models which are presented to study the hydroelastic behaviors of a ribbon pontoon bridge sub- jected by a moving load with different water depths.One model is the analytical model based on beam theory,and the other is the BEM model based on potential theory.The action of water is studied by BEM on the basis of potential theory.The vibra- tion differential equation of a floating bridge can be deduced with the combination of added mass and structures'mass,the combination of damping coefficient and structures'damping,and the combination of resilience and moving loads.The formulae of hydroelastic frequencies and dynamic responses are provided by using the assumed mode method.The results indicate that water depth have little influence upon the hydroelastic frequencies and dynamic responses of the floating bridge,so that the effect of water depth can be negligible during the design of floating bridge.