典型峡谷平均风速分布特性及跨谷管道悬索桥静风稳定性分析

发布时间：2018-01-04 07:27

本文关键词：典型峡谷平均风速分布特性及跨谷管道悬索桥静风稳定性分析　出处：《西南交通大学》2017年硕士论文　论文类型：学位论文

【摘要】：山区交通建设需要建造众多跨越峡谷的桥梁,进行跨谷桥梁抗风设计时,需要研究谷内风速分布特性及其对桥梁抗风性能的影响。本文采用计算流体力学对峡谷地形风场数值模拟研究,通过建立不同类型的简化峡谷模型,探究峡谷内平均风速的分布特性,总结了峡谷风在"狭管效应"作用下,风速在水平方向、高度方向以及沿峡谷方向的变化规律;采用峡谷风场测量与渠道流速分布研究成果,对本文数值模拟峡谷风速分布规律进行验证。静风稳定性问题是悬索桥抗风设计的重要内容之一,本文基于峡谷风场的研究,拟合出峡谷内桥跨方向的平均风速分布曲线,采用不均匀风速对某管道悬索桥进行静风稳定性分析,探究不同风速分布形式对悬索桥静风稳定性的影响。同时,论文对比了抗风索对该管道悬索桥静风稳定性的影响。本文研究表明,气流流经峡谷会产生风速放大现象,在水平方向上,从峡谷侧壁至峡谷中部,风速会随着摩擦作用的减弱迅速增大,风速在达到一个极大值后会进入一个变化相对缓和的阶段;在高度方向上,风速由谷底开始增大,在峡谷2/3高度位置附近达到一个最大值,随后沿高度方向降低;沿峡谷方向,风速的放大现象逐渐减弱,并趋于缓和。风速进入峡谷内弯曲段时,地形的改变会导致气流变向,同时横向方向风速的不均匀性增加。关于桥梁静风稳定性分析,在不同风速分布形式作用下,管道悬索桥的结构静风失稳临界风速发生改变。在桥跨方向风速平均值相同的情况下,跨中风速大于两侧风速的分布形式更易导致结构发生静风失稳现象。结果还表明,抗风索能有效降低管道悬索桥结构位移,极大提高其静风稳定性。
[Abstract]:The traffic construction in bridge construction needs many across the canyon, cross Valley bridge wind resistance design, need to study the valley wind speed distribution characteristics and its effect on bridge wind resistance. This paper uses CFD Research on Numerical Simulation of Canyon terrain wind field, by simplifying the canyon model establishment of different types of distribution, to explore the characteristics of the average wind speed in the canyon the wind in the canyon, summed up the "narrow tube effect" under the effect of wind speed in the horizontal direction, the height direction and direction changes along the canyon; the canyon wind field measurement and velocity distribution channel research, simulation of Canyon wind speed distribution in order to verify the feasibility of this numerical. The aerostatic stability of suspension bridge is one of the important content the wind resistant design, this paper studies the canyon wind field based on the fitting out of the canyon in the direction of the cross bridge average wind speed distribution curve, the uneven wind speed of a pipeline The suspension bridge static wind stability analysis, explore the impact of different wind speed distribution on aerostatic stability of suspension bridge. At the same time, the effect of the wind cable pipeline suspension bridge static wind stability. This study shows that air flows through the canyon will produce wind speed amplification phenomenon, in the horizontal direction, from the middle to the canyon walls Canyon wind speed will increase rapidly with the weakening of the friction effect, wind speed reaches a maximum value after the change will enter a relatively mild stage; in the height direction, wind speed from the bottom in the canyon began to increase, 2/3 height near reach a maximum and then decreases along the height direction along the canyon direction; amplification of the wind speed gradually weakened, and easing. Wind into the canyon in the bending section, the terrain changes cause the airflow to change, at the same time nonuniformity of the transverse direction of the wind speed increases. On the bridge, aerostatics Stability analysis in different wind speed distribution function, the critical wind speed change structure of pipeline suspension bridge. The bridge span in the direction of the average wind speed under the same value, the distribution form of cross wind speed is greater than the wind speed on both sides more easily occur in the structure of aerostatic instability phenomenon. The results also show that the wind resistance cable can effectively reduce the structural displacement of pipeline suspension bridge, greatly improve the static wind stability.

【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U448.25

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