Study on unsteady air force on low-rise buildings and numerical methods for prediction of wind load for wind resistant design

低层建筑非定常空气力研究及抗风设计风荷载预测数值方法

基本信息

批准号：
14350303
负责人：
MARUYAMA Takashi
金额：
$ 8.45万
依托单位：
Kyoto University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-14350303/
关键词：
low-rise buildings unsteady air force wind resistant design wind load typhoon strong wind damage prediction method numerical simulation 強風被害野外観測風洞実験風速変動風圧変動数値計算

项目摘要

We studied the wind characteristics of surface layer and the numerical methods for the prediction of wind load for wind resistant design of low-rise buildings.For the beginning, the wind characteristics of surface layer was studied using field experimental data. The spatial variations of turbulence statistics around the 2.4m cube were evaluated during rather strong winds and the correlated wind pressures on the wall and the roof was investigated. The results show that the upwind velocity fluctuations of streamwise component at a point with the height H, height of the cube, and the horizontal distance 0.9H from the cube have a rather strong correlation with the pressures on the upwind wall and the upwind portion of the roof.On the other hand, we also conducted field investigations of strong wind damage caused by typhoons and tatsumaki, tornado, struck Japan during the period of this study. The damages caused by some tatsumakis in 2001, by Typhoon 0314 struck on Miyakojima Island Okinawa prefecture in 2004 and by Typhoon 0418 struck on Miyajima Island Hiroshima prefecture in 2004 were studied. The extreme damage, such as completely failed houses, is decreasing but the damage on the roof or claddings is not decreasing. The secondary damage by flying debris, such as piece of broken roof tile or glass or gravels and so on, and the human damage are still large in number.Following above mentioned studies, it was resulted that the proper prediction of approaching wind and of wind characteristics in the urban areas near the ground is important for the wind resistant design of low-rise buildings. We showed some numerical methods using turbulent models introducing the effect of surface roughness, such as k-ε method and LES, for predicting the wind flow in the city areas for strong wind condition. Also the numerical method using PSU/NCAR MM5 was adopted to predict the strong wind caused by typhoon.

研究了表层风特性以及低层建筑抗风设计中风荷载预测的数值方法。首先，利用现场实验数据研究了表层风特性和湍流的空间变化。对2.4m立方体周围的强风进行了统计，并研究了墙体和屋顶上的相关风压，结果表明，立方体高度H处的流向分量的迎风速度波动。和水平距离距立方体0.9H与迎风墙和屋顶迎风部分的压力有相当强的相关性。另一方面，我们也对日本台风和龙卷风造成的强风损害进行了现场调查。 2001 年，2004 年 0314 号台风袭击冲绳县宫古岛，造成部分龙卷造成的损失。 2004 年袭击宫岛的广岛县的 0418 号台风造成的房屋完全倒塌等极端破坏正在减少，但屋顶或覆层的破坏却没有减少，碎片等飞散造成的二次破坏。屋顶瓦片或玻璃、碎石等的破碎，人为破坏的数量仍然较多。经过上述研究，得出了对城市来风和风特性的正确预测近地面区域对于低层建筑的抗风设计非常重要，我们展示了一些利用湍流模型引入表面粗糙度影响的数值方法，例如 k-ε 方法和 LES，用于预测城市地区的风流。针对强风情况，采用PSU/NCAR MM5数值方法对台风引起的强风进行预测。