高墩大跨连续刚构桥风致响应研究

发布时间：2018-01-15 02:34

本文关键词：高墩大跨连续刚构桥风致响应研究　出处：《云南大学》2014年硕士论文　论文类型：学位论文

【摘要】：高墩大跨连续刚构桥作为一种施工便捷、力学性能优越的公路桥型,越来越多被应用到跨越山川河谷的公路工程中。由于高墩大跨连续刚构桥结构本身通常具有高墩、轻质、柔性大的特点,加之桥址所在地特殊的风环境,因此,风荷载作用下高墩大跨连续刚构桥的风致响应和稳定性成为此类桥梁设计时的一个重要指标。本文基于公路桥梁抗风设计理论、抖振时程分析理论,采用有限单元分析方法,借助ANSYS/FLUENT、MATLAB、Midas Civil和ANSYS等软件,以一高墩大跨连续刚构桥—云南省凤庆县漭街渡大桥为研究对象,研究了高墩大跨连续刚构桥的风致响应。主要研究了漭街渡大桥主桥主梁多个变截面的三分力系数、漭街渡大桥在横桥向风荷载作用下的稳定性、漭街渡大桥的动风响应。论文的具体研究内容有： (1)根据漭街渡大桥桥址处地形地貌,按照《公路桥梁抗风设计规范》,计算了桥址场地基本风速,计算了漭街渡大桥最大悬双臂施工阶段、成桥无水阶段、成桥最大水位阶段主梁和主墩的设计基准风速； (2)基于CFD方法,运用有限元软件ANSYS/FLUENT,计算得到了漭街渡大桥主桥主梁多个变截面的三分力系数,拟合得到了三分力系数随梁高变化的函数和三分力系数随风攻角变化的函数。 (3)运用静阵风荷载法,计算了漭街渡大桥在最大悬臂施工阶段、成桥无水时期以及成桥桥墩最大淹没时期横桥向静阵风荷载的响应情况,比较了国内不同规范风荷载的简化计算方法,并分析了漭街渡大桥在横桥向风荷载作用下的稳定性。 (4)基于谐波叠加法,运用MATLAB软件,模拟得到了主桥47个位置处的脉动风速时程,并运用准定常风荷载计算理论将脉动风速时程转化为风荷载时程。 (5)运用抖振时程分析法,采用有限元软件ANSYS12.0,建立了漭街渡大桥最大悬臂施工阶段和成桥阶段的动、静风荷载计算模型,通过编制APDL参数化设计语言,计算了漭街渡大桥的动风响应。 (6)比较了不同风荷载下高墩大跨连续刚构桥风致响应的计算结果,形成了本文结论。论文的研究结果表明： (1)影响三分力的主要因素是梁高和风攻角。 (2)漭街渡大桥在横桥向静阵风荷载作用下的安全系数为6(大于4),横桥向静阵风荷载作用下的漭街渡大桥是安全的。 (3)漭街渡大桥抖振时域分析计算表明,抖振力响应较静力响应大,动力增大系数在1.1左右,并且最大悬臂施工阶段的动力增大系数比成桥阶段大；漭街渡大桥最大悬臂施工阶段的动力敏感程度大于其成桥阶段。 (4)采用时域分析法计算得到的漭街渡大桥风致总响应比采用《公路桥梁抗风设计规范》(JTG/TD60-01-2004)规定的阵风系数法所计算的风致总响应要大15%～30%。因此,需采用时域分析法对漭街渡大桥进行抖振时域分析,才能更精确地进行漭街渡大桥的抗风设计。
[Abstract]:High pier and long-span continuous rigid frame bridge is a highway bridge construction is convenient, excellent mechanical properties, has been more and more applied to highway crossing the mountains valley. Due to the high pier and long-span continuous rigid frame bridge with high piers are lightweight, flexible, large, coupled with the wind environment, the bridge site is located so special and the wind-induced response and stability of high pier and long-span continuous rigid frame bridge under wind load has become an important indicator of this kind of bridge design. This paper based on the theory of wind resistance design of highway bridge, buffeting time history analysis theory, the finite element analysis method, with the help of ANSYS/FLUENT, MATLAB, Midas Civil and ANSYS software, with a high pier and long-span continuous rigid frame bridge in Fengqing County of Yunnan province Mangjiedu bridge as the research object, the research of high pier and long-span continuous rigid frame bridge wind-induced response. The main study Mangjiedu bridge girder multiple variable The three component coefficient section, the stability of Mangjiedu bridge in cross bridge wind load, Mangjiedu bridge dynamic wind response.
The specific research contents of this paper are as follows:
(1) according to the Mangjiedu bridge at the bridge site topography, in accordance with the design specifications for highway bridges > >, the site of bridge site basic wind speed calculation, the calculation of maximum man Jie Du bridge suspension arms bridge construction stage, anhydrous stage, design stage based on the maximum water bridge girder and main piers of the quasi wind speed;
(2) based on the CFD method, using the finite element software ANSYS/FLUENT, calculated the Mangjiedu bridge main girder with variable cross-section of the three component coefficients, three component coefficient function with the beam height variation and three component coefficient with the change of wind attack angle function fitting.
(3) the use of static gust load calculation method, the man Jie Du bridge in cantilever construction stage, bridge and bridge pier during the absolute maximum submergence period transverse response of the static gust load, calculation method is simplified at different specification of wind load, and analyzes the stability of Mangjiedu bridge in action the transverse wind load.
(4) based on the harmonic superposition method, using MATLAB software, simulation has been the 47 position of fluctuating wind speed time history, and using the quasi steady wind load fluctuating wind speed into the wind load time history theory.
(5) the buffeting time history analysis method, using the finite element software ANSYS12.0, established the Mangjiedu bridge cantilever construction stage and finished stage of dynamic and static wind load calculation model, the design language of APDL parameters, Mangjiedu bridge dynamic wind response was calculated.
(6) the results of wind induced response of high piers and large span continuous rigid frame bridges under different wind loads are compared, and the conclusion of this paper is formed.
The research results of the paper show that:
(1) the main factors affecting the three force are the beam height and the wind attack angle.
(2) Mangjiedu bridge in the transverse direction of the bridge safety coefficient of static gust loading was 6 (more than 4), transverse static gust loading under Mangjiedu bridge is safe.
(3) Mangjiedu bridge buffeting analysis show that buffeting force response than the static response, dynamic increase factor of around 1.1, and the power of the largest cantilever construction stage increase coefficient than the bridge phase; Mangjiedu bridge cantilever construction stage of the dynamic sensitivity of the bridge is larger than that of the stage.
(4) the time domain analysis method to calculate the wind-induced response of Mangjiedu bridge total than the design specification for highway bridges < > (JTG/TD60-01-2004) wind gust coefficient method stipulated by the calculated total response to 15% ~ 30%., therefore, the need for Mangjiedu bridge buffeting analysis using time domain analysis method, in order to a more accurate wind resistant design of Mangjiedu bridge.

【学位授予单位】：云南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.23;U441.3

【参考文献】