开孔结构内部风效应的风洞试验研究

Wind tunnel study on internal wind effect for structure with openings

采用刚性模型风洞试验研究结构开孔时的内部风效应。设计制作了具有不同开孔状态的低层房屋模型进行多参数对比风洞试验,研究了开孔结构风致内压的空间分布特性,阐述了风致平均内压及脉动内压的产生机理,给出了平均内部风压系数与均方根内部风压系数的理论估算方法,并与试验结果进行了对比,通过对风压系数时程的分析,探讨了内部风压峰值因子的取值规律及内外压的相关性特性。研究表明风致内压在空间上分布均匀且采用理论方法进行内部风压估算是可行的,在结构设计中有必要提高内部风压峰值因子的取值并考虑内外部风压的联合效应。

Wind tunnel tests of rigid model were carried out to investigate the internal wind effect for structure with openings, A series of low-rise building models with various opening conditions were designed and multiparameter comparison wind tunnel tests were conducted. The space distribution characteristic of internal pressure was reported and the mechanics of wind-induced mean internal pressure and fluctuating internal pressure were studied. Theoretical methods for estimating mean and root-meansquare internal pressure coefficient were introducedand the theoretical results were compared with the test ones. Through analyzing time histories of wind pressure coefficients, the rules of selecting peak factor of internal pressure and correlation coefficient of internal-external pressure were extracted. It is shown that the distribution of internal pressure is uniform and estimating internal pressure theoretically is feasible. Increasing peak factor of internal pressure and considering combination effect of internal-external pressure are necessary in structural design.