球形屋面风压系数风洞试验研究  

Research on wind tunnel tests of wind pressure coefficients on dome roofs

作　　者：陈波[1] 周晶[1] 钟朋朋 杨庆山[1] 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044

出　　处：《建筑结构》2014年第10期73-78,共6页Building Structure

基　　金：国家自然科学基金(91215302;51378059);中央高校基本科研业务费专项资金(2010JBZ011)

摘　　要：对5个小矢跨比球形屋面进行了刚性模型测压风洞试验,研究其平均风压系数和风压极值分布,并与中国、日本和美国规范进行了对比。试验结果表明:矢跨比对球形屋面平均风压系数的分布影响显著,当矢跨比较大时,迎风区出现正压,最大负压出现在屋面顶部;而当矢跨比较小时,整个屋面均为负压,最大负压分别出现在屋面迎风前缘和屋面顶部,且常常前者幅值大于后者。各国规范与风洞试验的对比结果表明:对于屋面大部分区域,中国规范的规定值总体偏于保守,对小矢跨比球形屋面的迎风区域负压值估计不足;球形屋面出现较大的负压极值风压系数,极值风压系数在屋面的大部分中间区域的变化梯度小,而在屋面边缘位置的变化梯度大。基于风洞试验结果,给出了屋面分区平均风压系数和极值风压系数建议值。Mean and peak wind pressure coefficients on dome roofs with five different rise-span ratios were investigated with wind tunnel tests,and the experiment results were compared to those in Chinese,Japanese and American building codes. Test results show that the rise-span ratio has important effects on the distribution of mean wind pressure coefficients. Positive pressure occurs on the windward roof area,and the maximum suction occurs on the roof apex for the roof with a big rise-span ratio. Suction occurs on the whole roof,the big suction occurs on the windward and the roof apex for the roof with a small rise-span ratio,and the suction amplitude on the windward edge is usually larger than the value on the roof apex. Results obtained by comparing Chinese,Japanese and American building codes with wind tunnel tests show that mean wind pressure coefficients on the most of the roof are conservative in Chinese building code,but it underestimates the values on the windward edge roof area. Large peak suction occurs on dome roofs,and the values of peak wind pressure coefficients in the most of inner roof area are similar,but those on the edge area change greatly. The mean and peak wind pressure coefficients are proposed for different roof zones on the basis of the experiment results.

关 键 词：球形屋面 风洞试验 矢跨比 平均风压系数 极值风压系数 

分 类 号：TU312.1[建筑科学—结构工程]