摘要
通过刚性模型测压试验研究了低矮房屋屋面细部构造的风荷载特性。通过对不同高度和细部构造是否同时存在时屋脊、出山及檐沟风压系数及阻力系数的研究发现:在来流斜风向吹向细部构造的外表面(屋脊为迎风面)时,内侧表面(屋脊为背风面)端部负压变化剧烈,幅值很大,造成朝向屋面(屋脊为朝向背风面)的最不利极值净风压系数很大,其中出山最大,达到18.0左右,屋脊次之,为10.5左右,檐沟最小,为7.0左右;而背离屋面(屋脊为朝向迎风面)方向的极值净风压则相对平稳。在同一竖直平面上,出山位置较低的测点比较高的测点最不利极值净负压系数要大5左右,檐沟则是大0.8左右;屋脊和出山在另外2个细部构造存在时,最不利极值净风压系数会减小很多,分别从10.5和18.0减小到只有7.5和6.0,檐沟减幅较小,从7减小到6。出山和檐沟的最不利阻力系数的幅值随着高度的增加会加大,当屋脊和檐沟存在后出山的最不利阻力系数的幅值会有所减小,但另外2个细部构造是否存在对屋脊和檐沟的阻力系数影响较小。
This paper studied the loads on the configuration details of low-rise building roofs by the rigid model pressure measurement tests, which were often destroyed in wind disasters. The pressure coefficients and drag coefficients of the ridge, protruding gable wall and eaves gutter were examined, which were of varied heights and with or without the other 2 types of configuration details. The results show that the negative pressure of interior surface （the leeward surface for the ridge） of the configuration details end varies severely and the amplitude occurs when the wind obliquely blows to the exterior surface（the windward surface for the ridge）, which leads to the very large worst peak net pressure coefficient towards the roof. The worst peak net pressure coefficients of the protruding gable wall, ridge and eaves gutter are about 18.0, 10.5 and 7.0, respectively. However the peak pressure away from the roof （towards the windward surface for the ridge） is relatively stable. The worst peak net negative pressure of the lower tap is 5 larger than that of the higher tap on the same vertical plan of the protruding gable wall,while that of the lower tap is only 0.8 larger than that of the higher tap for the eaves gutter. When the roof is equipped with the other 2 types of configuration details, the worst peak net negative pressure coefficients of the ridge and protruding gable wall decrease much to 7.5 and 6.0 from 10.5 and 18.0, respectively, while that of the eaves gutter decreases to 6 from 7. The worst peak drag coefficients of the ridge and eaves gutter are not affected by whether the roof is attached with the other 2 types of configuration details or not, while that of the protruding gable wall is smaller when the roof is attached with ridge and eaves gutter. The worst peak drag coefficients of the protruding gable wall and eaves gutter are larger with the increase of each height.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2012年第1期65-71,共7页
Journal of Building Structures
基金
国家自然科学基金项目(51178352)
关键词
低矮房屋
屋脊
出山
檐沟
风洞试验
最不利极值净压系数
阻力系数
low-rise building
ridge
protruding gable wall
eaves gutter
wind tunnel test
worst peak net pressure coefficient
drag coefficient
