某景观烟囱顺风向风振响应分析与风振系数确定
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(1 哈尔滨工业大学土木工程学院,哈尔滨 150090; 2 东北电力设计院,长春 130021)[摘要]采用SAP2000软件建立了某景观烟囱的结构分析模型,输入风荷载时程进行风振响应分析。考虑了烟囱复杂外形和不规则质量分布,利用频域方法计算了烟囱第1阶振型的风振位移响应,并与时域方法的结果进行对比,二者吻合较好。分别采用阵风荷载因子法和惯性风荷载法计算了烟囱结构不同高度处的风振系数,并将基于该两种风振系数的等效静力风荷载分别作用在烟囱结构上,计算其顺风向位移响应并与精确值进行比较,结果表明其位移分布均符合真实响应。因此虽然上述两种方法得到的风振系数沿高度分布差别较大,但均能实现烟囱的风振位移等效,均是合理的。为工程应用方便,采用基于阵风荷载因子法的风振系数供结构设计使用。[关键词]风振系数;烟囱;时域;频域;阵风荷载因子法;惯性风荷载法Analysis on along-wind-induced responses and determination of gust response factor on a landscape chimneyZhang Wenyuan1, Zheng Chaorong1, Zhang Yaochun1, Wu Yue1, Sun Yusong2(1 School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China;2 Northeast Electric Power Design Institute, Changchun 130021, China)Abstract:Based on the finite element model of a landscape chimney by SAP2000 and wind load history, the dynamic responses of the chimney were analyzed using time domain method. Also, wind-induced displacements of chimney’s first mode were calculated using the frequency domain method, in which the uneven distribution of width and mass was taken into account, and the results are close to the responses from time domain analysis. Both the gust loading factor method and the inertial wind load method were selected to calculate the gust response factors along the height of chimney, and distribution of wind-induced displacements by the equivalent static wind loads based on the above methods agrees well with the exact displacements. So the two methods can both acquire reasonable gust response factors and realize the displacements equivalence of chimney, though distributions of the gust response factors have great difference. Lastly, the gust response factors calculated from the gust loading factor method are recommended for reference of practical design, as for convenience of application.Keywords:gust response factor; chimney; time domain; frequency domain; gust loading factor; inertial wind load作者简介:张文元,博士,副教授,Email:hitzwy@163.com。参考文献[1]GB50009—2001建筑结构荷载规范[S]. 北京: 中国建筑工业出版社, 2002.[2]GBJ135—90高耸结构设计规范[S]. 北京: 中国建筑工业出版社, 1990.[3]郑朝荣, 张文元, 张耀春, 等. 某发电厂景观烟囱的风载体型系数研究[J]. 工业建筑, 2008,38(S1):259-263.[4]AHSOM KAREEM. Dynamic response of high-rise building to stochastic wind loads[J]. J. Wind Engineering and Industial Aerodynamics, 1992, 41-44: 1101-1112.[5]TSUKAGOSHI H,et al. Response analysis of along-wind and across-wind vibrations of tall buildings in time domain[J]. J. Wind Engineering and Industrial Aerodynamics, 1993, 46-47: 497-506.[6]陈波. 张拉膜结构风振响应分析[D]. 哈尔滨: 哈尔滨工业大学, 2003.[7]黄本才.结构抗风分析原理及应用[M]. 上海:同济大学出版社,2001.[8]埃米尔·希缪, 罗伯特·H·斯坎伦著. 风对结构的作用——风工程导论[M]. 刘尚培, 项海帆, 谢霁明, 译. 上海:同济大学出版社,1992.[9]DAVENPORT A G. Gust loading factors [J]. Journal of the Structural Division, 1967, 93(ST3): 11-34.[10]ZHANG X T. The current Chinese code on wind loading and comparative study of wind loading codes [J]. Journal of Wind Engineering and Industrial Aerodynamics, 1988, 30: 133-142.