高层建筑边角凹凸对体型系数分布的影响

Influence of high-rise building's concave convex corner on wind load shape coefficient distribution

通过风洞试验,研究多边形截面高层建筑边角凹凸对风载体型系数分布的影响.探讨不同边角凹凸的正方形及八角形等7种典型多边形截面的平均风压体型系数和极值风压体型系数的分布特征,并与规范十字形截面和CAARC标模进行比较;分析各种截面的风压敏感点位置,提出抗风最有利的截面形式.研究发现,0°风向角下迎风直角切角的体型系数与规范十字形有很大差异;十字形,深、浅锯齿,带凹槽的浅锯齿正方形截面的来流分离点不一致,凹槽可以缓和切角处的气流分离,使切角和中间区域的体型系数趋于一致;比较这4种截面形式,认为带凹槽的浅锯齿正方形截面为最优截面,浅锯齿正方形截面为最不利截面.

The influence of polygon high-rise building＇s concave convex corner on the wind load shape coefficients distribution was analyzed based on the wind tunnel tests.The distribution characteristics of mean wind pressure shape coefficients and extreme wind pressure shape coefficients of seven representative polygon sections with different concave convex corners were analyzed and compared with both the standard crisscross section and the CAARC mode.The best section for wind-resistant was presented according to the analysis of wind pressure sensitive position of seven cross-sections.Results show that the upwind right-cutting angle＇s shape coefficients are inconsistent with the standard crisscross.The incoming flow＇s separation points of four sections,including crisscross,deep,shallow serrated square and shallow serrated square cross-section with a groove are different.Groove makes the shape coefficients of cutting angle and middle area uniform by mitigating the separation of flow in the cutting angle.By comparing these four cross-sections,the shallow serrated square cross-section with a groove is considered to be the optimal section,while the shallow serrated square cross-section is the most unfavorable section.