矩形高层建筑非高斯风压时程峰值因子计算方法

发布时间：2018-10-08 17:12

【摘要】：对一矩形高层建筑进行刚性模型风洞测压试验。首先基于风压时程的3阶矩和4阶矩,对不同风向下,矩形高层建筑表面风压脉动的高斯区与非高斯区进行划分。结果表明,迎风面的非高斯区主要位于迎风边缘及角部。在侧风面,长边迎风时,非高斯区主要集中在迎风前缘附近;短边迎风时,非高斯区位于靠近背风边缘的旋涡再附区。其次,基于Hermite级数法和改进Hermite级数法,通过参数分析和脉动风压谱拟合,提出非高斯风压时程的峰值因子简化计算方法——三参数Hermite级数法。最后,分别通过风压时程中的瞬时极值和风压时程的频数分布直方图验证了Hermite级数法、改进Hermite级数法和三参数Hermite级数法的有效性与准确性。结果表明,与风压时程中瞬时极值所对应的峰值因子相比,Hermite级数法的计算结果则偏于保守,三参数Hermite级数法、改进Hermite级数法的计算结果与其偏差率均小于10%。此外,三参数Hermite级数法和改进Hermite级数法所给出的概率密度曲线基本重合,且与实际风压时程频数分布直方图的贴合程度较优,能够较为准确地反映实际风压时程的概率密度分布。
[Abstract]:A rigid model wind tunnel test was carried out on a rectangular high-rise building. Firstly, based on the third and fourth moments of the wind pressure history, the Gao Si region and the non-Gao Si region of wind pressure pulsation on the surface of rectangular high-rise building are divided under different wind directions. The results show that the non-Gao Si area on the windward is mainly located at the edge and corner of the windward. On the side wind surface, the non-Gao Si area is mainly located near the front edge of the windward, while on the short side, it is located in the vortex reattachment area near the leeward edge when the long side is upwind. Secondly, based on Hermite series method and improved Hermite series method, through parameter analysis and pulse wind pressure spectrum fitting, a simplified calculation method of peak factor of non-Gao Si wind pressure history, the three-parameter Hermite series method, is proposed. Finally, the validity and accuracy of the Hermite series method and the improved Hermite series method and the three-parameter Hermite series method are verified by the instantaneous extreme value in the wind pressure process and the frequency distribution histogram of the wind pressure time history, respectively. The results show that compared with the peak factor corresponding to the instantaneous extreme value in the wind pressure process, the calculation results of the Hermite series method are conservative, and the calculation results of the three-parameter Hermite series method and the improved Hermite series method and the deviation rate of the modified Hermite series method are less than 10 parts. In addition, the probability density curve obtained by the three-parameter Hermite series method and the improved Hermite series method basically coincides with the actual wind pressure time-history frequency distribution histogram. It can accurately reflect the probability density distribution of the actual wind pressure time history.
【作者单位】：同济大学土木工程学院建筑工程系;同济大学建筑设计研究院(集团)有限公司;
【基金】：国家自然科学基金青年基金项目(51408353) 上海市青年科技启明星计划项目(15QB1404800)
【分类号】：TU973

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