考虑参数影响的斜拉桥π形断面的静风效应研究  

Research on Static Wind Effect of π-shaped Section of Cable-stayed Bridge Considering the Influence of Parameters

作　　者：王向阳[1] 张帅辉 宋大为 WANG Xiang-yang;ZHANG Shuai-hui;SONG Da-wei(School of Transportation,Wuhan University of Technology,Wuhan 430063,China)

机构地区：[1]武汉理工大学交通学院,武汉市430063

出　　处：《公路》2022年第1期126-134,共9页Highway

基　　金：国家自然科学基金项目,项目编号51178361;湖北省自然科学基金项目,项目编号2013CFB342。

摘　　要：基于计算流体动力学(CFD)数值计算方法,通过商用软件FLUENT对一座π形主梁断面的拟建斜拉桥进行抗风性能分析,得到成桥状态下主梁断面周围流场的压力、速度分布以及不同风攻角下的静力三分力系数。在此基础上,研究了桥面横坡、护栏、高宽比等设计参数的变化对该桥主梁断面静风三分力系数的影响。研究结果表明,桥面横坡坡率的变化对阻力系数有较大影响,设计采用2.0%横坡时的主梁断面受风阻影响相对较小,在设计时可将不设横坡的桥梁断面作为设计基准;对比成桥状态有护栏工况和施工阶段无护栏工况时的三分力系数发现两者差异较大,在桥梁抗风设计时有必要对这两种工况分别计算分析;对不同梁高时的三分力系数进行分析发现该桥梁高在设计梁高的±12.0%变化范围内对桥梁断面的钝性特征影响并不大,设计时可以在此基础上综合其他因素选择合适的梁高。Based on the computational fluid dynamics(CFD) numerical calculation method, in this paper the commercial software FLUENT is used to analyze the wind resistance performance of a proposed cable-stayed bridge with a π-shaped main girder. The distribution of pressure and velocity in the flow field around the main girder section and the static force three component coefficients at different angles of attack are identified.On this basis,the influence of the changes of design parameters such as the cross slope,guardrail and aspect ratio of the bridge deck on the static wind three-component force coefficient of the main girder of the bridge is studied.The research results show that the change of the cross slopes of the bridge deck has a greater impact on the resistance coefficient.When the design adopts a 2.0%cross slope,the main girder section is relatively less affected by wind resistance.The bridge section without a cross slope can be used as the design benchmark during the design;comparing the three-component force coefficients when the bridge is completed with guardrails and without guardrails at the construction stage,it is found that there is a big difference between the two.It is necessary to calculate and analyze these two working conditions separately in the bridge wind resistance design;when analyzing the three-component force coefficients of different beam heights,it is found that the bridge height within the design beam height±12.0 has little effect on the blunt characteristics of the bridge section.In the design,the appropriate beam height can be selected on this basis in combination with other factors.

关 键 词：斜拉桥 π形梁 三分力系数 桥面横坡 护栏 高宽比 

分 类 号：U442.59[建筑科学—桥梁与隧道工程] U448.27[交通运输工程—道路与铁道工程]