非均匀质量高层结构风振基底剪力计算研究  

Study on Calculation of Wind-induced Base Shear Force of Non-uniform Mass Tall Buildings

作　　者：周云[1] 周和鸿 吴玖荣[2] ZHOU Yun;ZHOU Hehong;WU Jiurong(School of Civil Engineering and Transportation,Guangzhou University,Guangzhou 510006,China;Research Center for Wind Engineering and Engineering Vibration,Guangzhou University,Guangzhou 510006,China)

机构地区：[1]广州大学土木与交通工程学院,广东广州510006 [2]广州大学风工程与工程振动研究中心,广东广州510006

出　　处：《湖南大学学报（自然科学版）》2024年第11期65-73,共9页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(52378497)。

摘　　要：针对荷载规范中顺风向等效静力风荷载计算公式难以准确评估非均匀质量的高层结构基底剪力,提出竖向空间相关性折算系数η_(z)和质量转换系数m_(cn),分别考虑了多自由度体系与无限自由度体系两者竖向空间相关性的差异和质量非均匀分布对基底剪力的影响,对规范方法进行改进,结合两个算例进行验证;同时分析振型系数、建筑高度和地貌类型对η_(z)的影响.研究表明:竖向空间相关性折算系数η_(z)能反映多自由度体系与无限自由度体系两者竖向空间相关性的差异对基底剪力的影响,算例考虑该影响与否的误差分别为1.2%和2.8%;质量转换系数m_(cn)能反映质量非均匀分布对基底剪力的影响,算例考虑该影响与否的误差为小于5%和等于28.5%;两系数结合规范方法可准确计算非均匀质量高层结构风振基底剪力.η_(z)随着地面粗糙度增加和建筑高度增加而增大,随着指数型振型系数的指数增大而减小;η_(z)参数分析的最小值为0.922,误差可达5%以上;当设计不考虑多自由度体系和无限自由度体系两者竖向空间相关性的差异对基底剪力的影响时,按多自由度体系计算是偏于安全的.针对不同工程,质量转换系数m_(cn)取值需根据具体楼层质量与振型系数计算确定.As it is difficult to accurately evaluate the base shear force of a tall building with non-uniform mass under the equivalent static wind pressure calculated according to the load code,the vertical spatial correlation conversion coefficientη_(z) and mass conversion coefficient m_(cn) are proposed to consider the effects of the difference in vertical spatial correlation between multi-degree-of-freedom and infinite-degree-of-freedom systems and non-uniform mass distribution on the base shear forces,respectively,modifying the Chinese load code method in the calculation of the wind-induced base shear forces of non-uniform mass high-rise structures.Moreover,it is validated through two example analysis,respectively.The effects of the vibration mode coefficient,building height,and geomorphology on the vertical spatial correlation conversion coefficientη_(z) are analyzed in terms of parameters.The results show that the vertical spatial correlation conversion coefficientη_(z) can reflect the effect of the difference in vertical spatial correlation between multi-degree-of-freedom and infinite-degree-of-freedom systems,and the errors in the case study considering this effect or not are 1.2%or 2.8%,respectively;the errors in the case study considering non-uniform mass or not are less than 5%or 28.5%respectively,which indicates that the mass conversion coefficient m_(cn) can reflect the effects of the mass non-uniform distribution on the base shear forces;and the combination of two coefficients with the load code method can accurately calculate the wind-induced base shear forces of high-rise structures with non-uniform mass.The vertical spatial correlation conversion coefficient increases with the increase of ground roughness and building height,and decreases with the exponential increase of the exponential vibration mode coefficients;the minimum value ofη_(z) in parameter analysis is 0.922,and the error can be more than 5%;without consideration of the effect of the difference in vertical spatial correlation between multi-

关 键 词：高层建筑 荷载规范 基底剪力 竖向空间相关性折算系数 质量转换系数 

分 类 号：TU355[建筑科学—结构工程]