玻璃景观桥风荷载特性及风致振动舒适度评价

发布时间：2018-06-11 20:16

本文选题：景观桥 + 抗风性能　；参考：《西南交通大学》2017年硕士论文

【摘要】：随着经济快速发展、桥梁设计水平的提高,设计师们越来越关注桥梁结构的美学特性,近年来旅游业的快速发展推动了风景区内玻璃景观桥梁的建造。此类景观桥不仅造型独特结构新颖,而且多建于风速很大的悬崖边、峡谷上,风作用明显,但相关的研究较少。本文以某玻璃景观桥为工程背景,采用风洞试验与有限元计算相结合的方式,对玻璃景观桥的风致振动舒适度以及风荷载特性进行研究,本文主要工作及结论如下:1.分析了某玻璃景观桥的结构动力特性,为拟弹性模型风洞试验提供了必要的参数,计算结果表明该桥振动基频较高。2.对玻璃景观桥进行了刚性模型和拟弹性模型试验,得到了不同风攻角和风向角工况下结构的风荷载特征、涡激振动性质以及抖振响应,试验风速内,场地模型对整个测力模型的风场影响较为明显,测力试验的静力五分力系数变化较大,当山体处于桥体背风侧的几个风偏角时,考虑到风洞地面与山体引起流场及涡旋的变化,导致升力系数数值在该风偏角范围内较大。没有观察到涡激共振的产生。3.对常用的振动舒适度评价方法、各国规范中关于振动舒适度的规定进行了介绍与比较,并基于风洞试验结果对某玻璃景观桥进行了舒适度评价,比较中发现,仅IOS规范中对不同频率对振动舒适度的影响有所考虑,且很多规范未对人体更为敏感的横向振动进行考虑。4.基于风洞试验结果,利用有限元计算,结合结构自身受力特性,对风荷载作用下结构危险截面进行强度验算,将平均风产生的截面应力与振动部分作了对比,结果表明此类桥的风荷载主要来源于静力效应,动力效应的贡献很小。
[Abstract]:With the rapid development of economy and the improvement of bridge design level, designers have paid more and more attention to the aesthetic characteristics of bridge structure. In recent years, the rapid development of tourism industry has promoted the construction of glass Landscape Bridges in the scenic area. This kind of landscape bridge is not only unique in its unique structure, but also on the cliff edge of high wind speed, and the wind effect is clear in the canyon. In this paper, taking a glass landscape bridge as the engineering background, the wind tunnel test and finite element method are used to study the wind-induced vibration comfort and wind load characteristics of the glass landscape bridge. The main work and conclusion are as follows: 1. the structural dynamic characteristics of a glass landscape bridge are analyzed, which is a quasi projectile. The wind tunnel test of sexual model provides the necessary parameters. The calculation results show that the rigid model and pseudo elastic model test of the bridge with high vibration base frequency.2. are carried out on the glass landscape bridge. The wind load characteristics, the characteristics of vortex induced vibration and the buffeting response are obtained under the different wind attack angle and the wind direction angle, and the field model is the whole in the test wind speed. The influence of the wind field of the dynamometer model is more obvious, and the static five force coefficient of the force test varies greatly. When the mountain is in the wind deflection angle of the leeward side of the bridge body, considering the change of the flow field and the vortex in the wind tunnel ground and the mountain body, the lift coefficient value is larger in the range of the wind deflection angle. There is no observation of the generation of.3. pair of the vortex excited resonance. The commonly used evaluation method of vibration comfort degree is introduced and compared in various countries, and the comfort degree of a glass landscape bridge is evaluated based on the wind tunnel test results. It is found that the influence of different frequencies on the vibration comfort is considered only in the IOS specification, and many specifications are not more for the human body. On the basis of the wind tunnel test results, the sensitive lateral vibration is based on the wind tunnel test. Using the finite element calculation and combining the mechanical behavior of the structure, the strength of the structural dangerous section under the wind load is calculated. The cross section stress produced by the average wind is compared with the vibration part. The results show that the wind load of this kind of bridge is mainly derived from the static effect and the dynamic force. The contribution of the force effect is very small.
【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】：U441

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