大跨窄钢桁加劲梁悬索桥气动性能研究

发布时间：2018-06-11 15:06

本文选题：大跨钢桁悬索桥 + 颤振导数　；参考：《中南大学》2014年硕士论文

【摘要】：摘要：钢桁架悬索桥以其跨越能力较强、造价低廉等优点,成为了跨越峡谷、河流以及水库的有效工具。由于这种桥梁的缺点是桥面窄、桁高矮、轻而柔、结构阻尼小,对风的作用十分敏感,因此其抗风性能是决定桥梁设计方案的关键因素,对钢桁架悬索桥气动性能的研究具有重要意义。本文借助数值模拟和风洞试验方法,对石登悬索桥主梁气动力系数和颤振稳定性进行了深入研究,完成的主要工作有： 1、讨论了实面积比和间距比对主桁架各杆件风载阻力系数的影响；另外分析了H型和矩形截面形式的杆件对主桁架节段三分力系数的影响。 2、建立了石登悬索桥在施工和成桥状态下主梁的三维CFD数值分析模型,探讨了风速、风攻角及主桁架间距比对主梁三分力系数的影响。 3、开展了石凳悬索桥主梁节段模型静力三分力试验研究。分别制作了缩尺比1：15的主梁施工状态及成桥状态节段模型,得到了不同风速及不同风攻角下主梁的三分力系数,并对数值模拟和风洞试验结果进行了比较分析。 4、建立了悬索桥成桥状态主梁数值模型,计算了悬索桥成桥状态主梁的颤振导数,根据Scanlan推导的颤振临界风速计算方法得到成桥状态颤振临界风速。另外,探讨了间距比对主梁颤振稳定性的影响。
[Abstract]:Abstract: steel truss suspension bridge has become an effective tool for crossing canyons, rivers and reservoirs because of its advantages of strong span ability and low cost. Because the disadvantages of this kind of bridge are narrow deck, short truss, light and soft structure, low damping, and sensitive to wind, its wind-resistant performance is the key factor to determine the design scheme of the bridge. It is of great significance to study the aerodynamic performance of steel truss suspension bridge. The aerodynamic coefficient and flutter stability of the main girder of the steel truss suspension bridge are studied in this paper by means of numerical simulation and wind tunnel test. The main works are as follows: 1. The effect of real area ratio and distance ratio on wind load resistance coefficient of main truss member is discussed. In addition, the influence of H-shaped and rectangular cross-section members on the three-point force coefficient of the main truss segment is analyzed. 2. The three-dimensional CFD numerical analysis model of the main girder of the Shiden suspension bridge under the conditions of construction and completion is established, and the wind speed is discussed. The influence of wind attack angle and the ratio of main truss spacing on the three-point force coefficient of the main girder. 3. The static three-point test study of the main girder segment model of the stone bench suspension bridge was carried out. The segmental models of the construction state of the main beam and the state of the bridge are made respectively, and the three-point force coefficient of the main girder under different wind speed and angle of attack is obtained. The results of numerical simulation and wind tunnel test are compared and analyzed. 4. The numerical model of suspension bridge is established, and the flutter derivative of suspension bridge is calculated. The flutter critical velocity of bridge is obtained by the method of calculating flutter critical velocity derived by Scanlan. In addition, the effect of the spacing ratio on the flutter stability of the main beam is discussed.
【学位授予单位】：中南大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U448.25;U441.3

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