Vortex-induced oscillations of reinforced concrete chimneys and its wind tunnel studies using elastic models.

钢筋混凝土烟囱的涡激振荡及其使用弹性模型的风洞研究。

基本信息

批准号：
63550424
负责人：
TAMURA Yukio
金额：
$ 0.77万
依托单位：
Tokyo Polytechnic University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1988
资助国家：
日本
起止时间：
1988 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63550424/
关键词：
wind tunnel testing elastic model similarity law reinforced concrete vortex excitation Reynolds number Strouhal number drag coefficient レイノズル数鉄筋コンクリート煙突渦励動振ストローハル数

项目摘要

When the dynamic behavior of buildings or structures is simulated in the wind tunnel testings, the dynamic similarity requirements both of the wind characteristics and the structures should be satisfied. The model air density is usually equal to the full-scale air density. Therefore, in order to make the mass ratio identical, the material density of the model should be equal to that of the full-scale structure. When attention is paid on some particular reduced frequencies, e. g. the vortex resonance, the value of the elastic modulus of the material of the model restricts the windspeed of testings as well as the size of the model. The interested reduced frequency of the phenomena should be realized in the available windspeed range inherent to the wind tunnel and its facilities or instruments.The new material for the wind tunnel simulations of reinforced concrete structures is investigated and composed. The Epoxy resin was selected as the stuff of the material of the model. The density of the reinforced concrete is about 2.4g/cm^3 while the density of the Epoxy resin is 1.2g/cm^3. As the density of the Epoxy resin is smaller than that of the reinforced concrete, in order to make the mass parameter identical, the iron powder is added into the solvent.Then, the wind tunnel testings on the vortex-induced oscillations of a reinforced concrete chimney are carried out using a model made of this material. The dynamic behavior of the model is compared with the full-scale data, and it is confirmed that the material is available to the wind tunnel testings.Finally, the method for wind resistant design of the reinforced concrete structures with a circular section are proposed.

在风洞试验中模拟建筑物或结构的动力行为时，应满足风特性和结构的动力相似性要求。模型空气密度通常等于全尺寸空气密度。因此，为了使质量比相同，模型的材料密度应等于全尺寸结构的材料密度。当注意某些特定的降低频率时，例如。 g。涡旋共振，模型材料的弹性模量的大小限制了测试的风速以及模型的尺寸。所感兴趣的现象频率的降低应该在风洞及其设施或仪器固有的可用风速范围内实现。研究并合成了用于钢筋混凝土结构风洞模拟的新材料。模型材料选用环氧树脂。钢筋混凝土的密度约为2.4g/cm^3，而环氧树脂的密度为1.2g/cm^3。由于环氧树脂的密度小于钢筋混凝土的密度，为了使质量参数相同，在溶剂中加入铁粉，然后对钢筋混凝土的涡激振荡进行风洞试验。烟囱是使用这种材料制成的模型进行的。将模型的动力性能与全尺寸数据进行了对比，证实了该材料可用于风洞试验。最后，提出了圆形截面钢筋混凝土结构的抗风设计方法。