扰流板减小低矮房屋屋面风压试验研究

近年来，我国台风灾害频繁，在历次风灾中，大量村镇低矮房屋倒塌破坏是造成生命财产损失的重要原因。在强风中，屋面是低矮房屋最薄弱部分往往最先发生破坏。目前，提高屋面抗风能力的方法主要是增加屋面本身强度和整体性，但其经济成本较高且抗风效果并不理想。针对上述问题，文中提出一种气动抗风方法，在双坡房屋屋面增设扰流板，通过改变房屋气动性能来降低屋面风压，并围绕这一方法开展了风洞试验研究工作。试验结果表明：扰流板可以有效减小双坡房屋屋面风压，尤其对屋面局部极值风压减小效果显著，最大减小幅度可达49%。山墙处扰流板对屋面风压影响最大，其次是屋檐处的扰流板，屋脊处扰流板对屋面风压无显著影响。相对于扰流板宽度与高度，扰流板角度是对屋面风压影响最为明显的几何因素，屋檐处扰流板角度建议值为0?~30?，山墙处扰流板为10?~30?。综合考虑经济与构造措施等因素，扰流板高度建议值为挑檐高度的1/70~1/12，宽度为房屋长度的1/20。最后，根据实验结果给出了安装扰流板结构屋面风压折减系数和相关的设计建议。

Study on wind pressure on the roof of low-rise building alleviated by spoiler

In recent years, the typhoon disasters have been witnessed in China frequently, and a lot of low-rise buildings in villages have been destroyed in these disasters, which becomes the main reason of causing losses of life and property. For the low-rise buildings, the roof is the most vulnerable part in strong wind. The conventional wind-resistant measure is to increase strength and integrality of roof, which, however, is uneconomic and less effective. In the present study, a new aerodynamic measure of mounting spoilers on the gable roof is taken to mitigate the negative wind pressure. A lot of wind tunnel tests were conducted on a low-rise gable-roof building with spoilers to investigate the mitigation of wind pressure on the roof. The test results show that spoilers play an effective role of mitigating the wind pressure on gable-roof building, and especially for the local peak wind pressure, the maximum reduction percentage is about 49%. The spoilers mounted at the gable wall affect the wind pressure the most, next is the spoilers at the eave; the spoilers at the ridge have no remarkable influences on the wind pressure. Compared to the width and height of the spoilers, the angle of the spoilers shall be the most important factor influencing the reduction of wind pressure. The recommended angle for the spoilers at the eave shall be 0?~30?, and the recommended angle for the spoilers at the gable wall shall be 10?~30?. Based on the comprehensive considerations of economic and structural measures, the recommended height for the spoiler is 1/70~1/12 of the eave height, and the recommended width is 1/20 of the length of the whole building. According to the test results, some practical design suggestions and the reduction coefficients of wind pressure due to the mount of the spoilers are provided.