极端波浪作用下跨海箱形桥梁上部结构流固耦合特性研究  

Fluid-structure interaction characteristics of superstructure of a cross-sea box bridge under extreme wave action

作　　者：黄博[1] 唐尧 杨志莹 祝兵[2] 屈建强 HUANG Bo;TANG Yao;YANG Zhiying;ZHU Bing;QU Jianqiang(School of Civil Engineering,Chongqing Jiaotong University,Chongqing 400074,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;Chongqing Urban Investment Infrastructure Construction Co.,Ltd.,Chongqing 400000,China)

机构地区：[1]重庆交通大学土木工程学院,重庆400074 [2]西南交通大学土木工程学院,成都610031 [3]重庆城投基础设施建设有限公司,重庆400000

出　　处：《振动与冲击》2023年第17期210-219,共10页Journal of Vibration and Shock

基　　金：国家自然科学基金青年基金项目(52008065);重庆市自然科学基金面上项目(cstc2021jcyj-msxmX1082)。

摘　　要：跨海桥梁面临着海洋环境中极端波浪的巨大威胁,波浪-结构的耦合作用特性是跨海箱形桥梁上部结构的极端波浪设计中需考虑的关键问题。采用OpenFOAM程序基于有限体积法离散不可压缩流体的Naiver-Stokes方程,并结合SST k-ω湍流模型模拟极端波浪的生成、传播及冲击作用,以弹簧-质量-阻尼系统模拟箱梁上部结构运动体系,并基于动网格方法构建极端波浪与箱梁上部结构相互作用的多相流耦合模型。通过与模型水槽试验结果和已有文献的仿真结果的对比验证该耦合模型的有效性,随后利用该耦合模型探究了波浪参数、结构特性及约束刚度等参数对箱形桥梁上部结构波浪荷载、动力特性及支座力的影响规律。结果表明:结构与流体的耦合效应导致箱形桥梁上部结构所受波浪荷载的波动增大和极值减小,其中水平波浪力最大降低28%,竖向波浪力最大降低22.5%,考虑流固耦合能更为合理地反映极端波浪作用下跨海箱形桥梁上部结构的实际波浪荷载;随着结构自振周期的增大,箱形桥梁上部结构所受的水平弹簧约束刚度下降,进而导致箱形桥梁上部结构的水平位移增大;在跨海桥梁上部结构的支座设计中不仅需要考虑上部结构所受波浪荷载,还应考虑结构运动及流固耦合效应对支座力的影响。Cross-sea bridges face a huge threat from extreme waves in ocean environment,and wave-structure interaction characteristics are key issues to consider in extreme wave design of superstructure of cross-sea box bridges.Here,OpenFOAM program was used to discretize Naiver-Stokes equation for incompressible fluid based on the finite volume method,and SST k-ωturbulence model was combined to simulate generation,propagation and impact action of extreme waves.A spring-mass-damping system was used to simulate motion system of box girder superstructure.Based on the dynamic grid method,a multi-phase flow coupled model for interaction between extreme waves and box girder superstructure was constructed.The effectiveness of this coupling model was verified by comparing its calculation results with results of model trough tests and existing literature simulation results.Then,this coupling model was used to investigate influence laws of wave parameters,structural characteristics and constraint stiffness on wave load,dynamic characteristics and support forces of box bridge superstructure.The results showed that the coupling effect between structure and fluid leads to increase in wave load fluctuations and decrease in extreme values of box bridge superstructure,the maximum reduction of horizontal wave force is 28%,and the maximum reduction of vertical wave force is 22.5%,so considering fluid-structure interaction can more reasonably reflect the actual wave load on superstructure of a cross-sea box bridge under extreme wave action;with increase in structure natural vibration period,the horizontal spring constraint stiffness of box bridge superstructure decreases to cause increase in horizontal displacement of box bridge superstructure;in support design of cross-sea box bridge superstructure,it is necessary to consider not only wave load acting on super-structure,but also effects of structural motion and fluid-structure interaction effect on support forces.

关 键 词：跨海桥梁 极端波浪 箱形桥梁上部结构 流固耦合 数值仿真 

分 类 号：U447[建筑科学—桥梁与隧道工程]