强/台风作用下挑蓬建筑屋盖的风场、风荷载和风致响应原型实测与风洞试验研究

The wind field characteristics around the cantilevered roofs is very complex, and the effects on wind pressure by the turbulent caused by roofs itself is also very significant. So at pensent both the wind tunnel test and numerical simulation method are still diffult to simulate the complicated wind load interaction mechanism. This project is aimed at explore the wind load mechanism on the surface of cantilevered roofs under stong wind and typhoon. Based on two prototype full-measurements bases on the southeast coastal area, this project plan to carry on the synchronization full-measurements and simulation experiment for the wind field, wind pressure and wind-induced response of cantilevered roofs in order to obtain the characteristics of wind load and wind-induced response of cantilevered roofs considering the wide range of influcing factors such as body shape, the rear ventilation rate, ratio of span height, wind direction and so on. Futhermore, the mean wind load model and fluctuating wind load model will be developed while reflecting the influences of strong wind/ typhoon and turbulence, the wind-induced response calculation method for large span cantilevered roofs will also be established while reflecting the the influences of strong wind/ typhoon, and the above wind load model will be futher developed based on the developed wind tunnel test. The experiment methods and theoretical results obtained by this project can be used to analyze the characteristics of wind load and wind-induced response for the cantilevered roofs of large stadium buildings on the coastal areas of our country.

挑蓬建筑屋盖周围流场的绕流特性十分复杂，表现为屋盖本身引起的特征湍流对风压场的影响非常显著，目前风洞试验和数值模拟难以模拟这一复杂的风荷载作用机理。本项目针对强/台风作用下悬挑屋盖表面的风荷载作用机理，基于东南沿海地区的原型实测基地，开展大跨度挑蓬建筑屋盖风场、风压、风致响应同步原型实测和模拟试验研究，揭示悬挑屋盖在强/台风作用下考虑不同体型、看台后部通风率、跨高比、风向角等各种因素影响的风荷载和风致响应特性，从而对现有挑蓬建筑屋盖的等效静力风荷载模型、风致动力响应计算和风洞试验方法进行完善，提出反映强/台风作用和特征湍流影响的平均和脉动风荷载模型，建立能反映强/台风作用的大跨度悬挑屋盖风致响应计算方法，并基于已完善的风洞试验对上述风荷载模型进一步完善和验证。本项目提出的试验方法和得到的理论成果可用于我国沿海强/台风作用下大型体育场等挑蓬建筑悬挑屋盖的风荷载特性和结构风致响应分析。

挑蓬建筑屋盖周围流场的绕流特性十分复杂，表现为屋盖本身引起的特征湍流对风压场的影响非常显著，目前风洞试验和数值模拟难以模拟这一复杂的风荷载作用机理。本项目针对强/台风作用下悬挑屋盖表面的风荷载作用机理，基于东南沿海地区的原型实测基地，开展大跨度挑蓬建筑屋盖风场、风压、风致响应同步原型实测和模拟试验研究，揭示悬挑屋盖在强/台风作用下的风荷载和风致响应特性，优化其等效静力风荷载模型、风致动力响应计算和风洞试验方法，提出反映强/台风作用和特征湍流影响的平均和脉动风荷载模型，建立能反映强/台风作用的大跨度悬挑屋盖风致响应计算方法。.研究获得了强/台风作用下挑蓬建筑的强/台风风场特性，如三维平均风速和风向、湍流度、阵风因子、湍流积分尺度、脉动风速谱、湍流相干性、空间相关性和概率分布特征等。获得了建筑表面和屋面的瞬时风压、脉动风压、风压概率分布风风压相关特征，以及风障对风场的影响和风特性的衰减规律。对实测模型房结构进行模型的风洞试验，通过分析平均风压、脉动风压和峰值风压的分布特征和统计特性以及随风向角变化的规律，揭示原型实测与风洞试验结果的差异和原因，优化建筑风洞试验方法，并获得体育场主看台挑蓬建筑的典型风灾机理。本项目提出的试验方法和得到的理论成果可用于我国沿海强/台风作用下大型体育场等挑蓬建筑悬挑屋盖的风荷载特性和结构风致响应分析。