大跨径钢箱梁最大悬臂状态非线性静风稳定性分析  

Nonlinear Static Wind Stability Analysis of Long Span Steel Box Girders in Maximum Cantilever State

作　　者：苗建宝 骆佐龙 MIAO Jianbao;LUO Zuolong(Xi′an Highway Research Institute Co.,Ltd.,Xi′an 710065,China;School of Electric Power,Civil Engineering and Architecture,Shanxi University,Taiyuan 030000,China)

机构地区：[1]西安公路研究院有限公司,西安710065 [2]山西大学电力与建筑学院,太原030000

出　　处：《交通科技》2023年第5期40-44,共5页Transportation Science & Technology

基　　金：陕西省交通科技项目(20-10K、20-04K);山西省自然科学研究面上项目(202203021221025);山西省高等学校科技项目(2021L010)资助。

摘　　要：港珠澳大桥跨越崖13-1气田管线桥施工最大悬臂状态受静风荷载作用可能存在静风失稳问题,影响结构正常施工与安全性。为解决上述问题,首先采用静力三分力系数法分析该桥最大悬臂状态设计基准风速作用下的静风效应,明确主梁各断面水平、竖向和扭转位移在不同初始风攻角条件下的发展变化规律;其次,对该桥最大悬臂状态不同初始风攻角作用下的非线性静风稳定性进行分析,基于控制断面的风速-扭转角变化曲线明确结构扭转发散临界风速;最后根据非线性静风稳定性分析结果对该桥最大悬臂状态的静风稳定性进行分析评价。结果表明,在正攻角范围内(0°~5°),主梁横向位移与扭转角最大值分别为-1.47 mm与0.023°,负攻角范围内(-5°~0°),主梁横向位移与扭转角最大值分别为为0.25 mm与-0.007°,在不同初始风攻角作用下结构稳定系数介于1.53~2.58之间。不同初始攻角作用下结构的临界风速介于63~109.6 m·s^(-1)之间,结构在负攻角范围内的临界风速计算值较正攻角高。The Hong Kong-Zhuhai-Macao Bridge-Crossing Ya 13-1 Gas Field Pipeline Bridge may suffer from static wind instability problem in the maximum cantilever state,which affects the normal construction and safety of the structure.In order to solve the problem,firstly,the static three-component force coefficient method was used to analyze the static wind effect of the maximum cantilever state of the bridge under the design reference wind speed,and the change rule of the horizontal,vertical and torsional displacement of each section under different initial wind attack angle was clarified.Secondly,the nonlinear static wind stability analysis of the bridge in the maximum cantilever state under different initial wind attack angle was conducted,and the critical wind speed of torsional divergence was determined based on the wind speed-torsional angle curve of the control section.Finally,the static wind stability of the bridge in the maximum cantilever state was analyzed and evaluated according to the nonlinear static wind stability analysis results.The results show that in the range of positive wind attack angle of(0°~5°),the maximum transverse displacement and torsional angle of the main beam are-1.47 mm and 0.023°respectively,while 0.25 mm and-0.007°in the range of negative attack angle of(-5°~0°),respectively.The structural stability coefficient ranges from 1.53 to 2.58 under different initial wind attack angles.The critical wind speed is between 63 m/s~109.6 m/s under the action of different initial wind attack angles,and the critical wind speed of the structure in the range of negative wind attack angle is higher than that of positive wind attack angle.

关 键 词：桥梁工程 港珠澳大桥 最大悬臂状态 静风稳定性 临界风速 

分 类 号：U442.59[建筑科学—桥梁与隧道工程] U441[交通运输工程—道路与铁道工程]