| 表面有螺旋装饰条的大跨贝壳形屋盖风荷载特性 |
| |
| 引用本文： | 林拥军,林池锬,周祎,刘开齐,潘毅.表面有螺旋装饰条的大跨贝壳形屋盖风荷载特性[J].西南交通大学学报,2021,56(2):261-271. |
| |
| 作者姓名： | 林拥军 林池锬 周祎 刘开齐 潘毅 |
| |
| 基金项目： | 国家自然科学基金（51608453）；国家重点研发计划资助项目（2016YFC0802205，2016YFB0303603-4） |
| |
| 摘 要： | 为了解装饰造型对大跨贝壳形屋盖风荷载特性的影响，研究了某表面有螺旋形装饰条高铁站房屋盖的风压分布特征. 首先，基于Reynolds时均RNG k-ε湍流模型，建立表面有装饰条大跨贝壳形屋盖的数值风洞模型，以模拟屋盖风压分布，通过与风洞试验结果的对比分析，验证了数值模型的可靠性和适用性；然后，建立表面无装饰条贝壳形屋盖的数值风洞，并进行数值模拟；最后，将表面有装饰条屋盖和表面无装饰条屋盖的计算结果进行对比，从风荷载升力系数、局部体型系数和局部区域速度矢量分布方面，分析表面有螺旋形装饰条贝壳形屋盖的风场变化特性. 研究结果表明:数值模拟得到的表面有装饰肋条大跨贝壳形屋盖风载体型系数与风洞试验的体型系数相对误差在 ± 25%以内，风荷载升力系数偏差率在?7.1%～6.1%；表面有装饰条模型的风载升力系数小于表面无装饰条模型，最大偏差率达22.4%，设置装饰条对大跨贝壳形屋盖的整体抗风有利；设置装饰条可以使屋面大部分区域的局部风压减小0～50%，但也会使得个别区域增大2～5倍，在对局部附属构件设计时应予以重点关注；装饰肋条间有一定的狭管效应，肋条对风流的阻挡效应致使风流在肋条处有明显的漩涡产生，并使得肋条自身的风压较高，表面有装饰条屋盖会在背风面产生比表面无装饰条屋盖更大范围的尾涡.
|
| 关 键 词： | 装饰条 贝壳形屋盖 升力系数 体型系数 尾涡 |
| 收稿时间： | 2019-05-26 |
Wind Load Characteristics of Large-Span Shell-Shaped Roof with Decorative Spiral Strips |
| |
| LIN Yongjun,LIN Chitan,ZHOU Yi,LIU Kaiqi,PAN Yi.Wind Load Characteristics of Large-Span Shell-Shaped Roof with Decorative Spiral Strips[J].Journal of Southwest Jiaotong University,2021,56(2):261-271. |
| |
| Authors: | LIN Yongjun LIN Chitan ZHOU Yi LIU Kaiqi PAN Yi |
| |
| Abstract: | In order to understand the effect of decorative structure on the wind load characteristics of a large-span shell-shaped roof, the wind pressure distribution characteristics of a high-speed railway station roof with a decorative spiral strip on a certain surface were studied. First, a numerical wind tunnel model for a long-span shell-shaped roof with decorative strips on its surface was established, and the wind pressure distribution on this roof was simulated on the basis of the Reynolds time-averaged RNG k-ε turbulence model. The reliability and applicability of the numerical model were then verified through comparative analysis against wind tunnel test results. Meanwhile, a numerical wind tunnel model for the same roof without decorative strips was also built, and numerical simulations were carried out. By comparing the numerical results of roofs with and without surface decorative strips, the wind field variation characteristics of the long-span shell-shaped roof with decorative spiral strips were analyzed from the aspects of wind-load lift coefficient, wind-load local shape coefficient, and regional velocity vector distribution. Results show that the relative error of the shape coefficient between the numerical simulation and the wind tunnel test was within ± 25%. The deviation rate of the wind-load lift coefficient was between ?7.1% and 6.1%. Compared with the simulation result of the roof without surface decoration strip, the wind-load lift coefficient of the roof with surfacedecoration strip was smaller, and the maximum deviation rate could reach 22.4%, which means that the setting of the decorative strip is beneficial for reducing the wind-resistance of the large-span shell-shaped roof. It was also found that the setting of decorative strips would reduce the local wind pressure in most areas of the roof by 0%–50%. However, it also increased the wind pressure in individual regions on the roof by 2–5 times, which should be paid more attention to in the design of local accessory components on the roof. Besides, there is some narrow pipe effect between the decorative strips, and the blocking effect of the decorative strips on airflow leads to the generation of apparent vortices between the strips, making the wind pressure at the strips higher. Furthermore, as the wind flows around the building, the roof with decorative strips on the surface will produce a larger range of trailing vortices on the leeward side than the roof without decorative strips. |
| |
| Keywords: | |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《西南交通大学学报》浏览原始摘要信息 |
|
点击此处可从《西南交通大学学报》下载全文 |
|
