摘要
基于斜风作用下结构静风荷载计算模型,考虑结构和静风荷载双重非线性因素,建立了斜风下大跨度桥梁三维非线性静风稳定性分析方法,并编制了相应的计算程序。以润扬长江大桥南汊悬索桥为研究对象,采用该程序进行不同风偏角和风攻角组合的非线性静风稳定性分析,探明了斜风效应对大跨度悬索桥静风稳定性的影响。结果表明:斜风下悬索桥的静风失稳形态仍然表现为主梁侧弯、竖弯和扭转耦合的空间失稳形态,斜风作用不改变悬索桥的静风失稳形态;斜风作用对悬索桥的静风稳定性存在正负效应,最低静风失稳临界风速出现在斜风情况下;静风失稳临界风速随初始风攻角的增加呈现偏态的倒U形变化规律,随着风偏角的增加,斜风作用对静风失稳临界风速的影响逐渐明显,影响幅度为-8%~6%,因此大跨度悬索桥静风分析需要充分考虑斜风的影响。
Based on the aerostatic load model of structures under skew wind and by considering the double nonlinear factors of structures and aerostatic loads,a computational method of 3D nonlinear aerostatic analysis for long-span bridges under skew wind is presented and the corresponding computational procedure is programmed.By taking the south branch suspension bridge of Runyang Yangtze River Bridge as an example,the nonlinear aerostatic stability analysis of the bridge under different combinations of wind yaw angle and wind attack angle is performed and the influence of skew wind on the aerostatic stability of the long-span suspension bridge is investigated.The results show that the aerostatic instability of the suspension bridge under skew wind still exhibits the lateral bending-vertical bending-torsion coupled spatial instability of the girder and the skew wind does not change the aerostatic instability mode.The skew wind has positive and negative effects on the aerostatic stability of the suspension bridge and the lowest critical wind speed of aerostatic instability appears in the case of skew wind.The critical wind speed of aerostatic instability exhibits a skew inverted U-shaped variation with the increase of initial wind attack angle.With the increase of wind deflection angle,the effect of skew wind on the critical wind speed of aerostatic instability increases gradually and the influential extent is between-8%and 6%.Therefore,the effect of skew wind needs to be fully considered in the aerostatic stability analysis of long-span suspension bridges.
作者
张新军
李寒妍
余天程
ZHANG Xinjun;LI Hanyan;YU Tiancheng(College of Civil Engineering,Zhejiang University of Technology,Hangzhou 310023,China;Key Laboratory of Civil Engineering Structures&Disaster Prevention and Mitigation Technology of Zhejiang Province,Hangzhou 310023,China)
出处
《浙江工业大学学报》
CAS
北大核心
2021年第6期642-649,共8页
Journal of Zhejiang University of Technology
基金
浙江省自然科学基金资助项目(LY18E080034)。
关键词
斜风
大跨度悬索桥
静风稳定性
三维非线性分析
skew wind
long-span suspension bridge
aerostatic stability
3D nonlinear analysis
