大高宽比方形截面高层建筑的横风向风荷载及风致响应研究
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(1 同济大学土木工程防灾国家重点实验室,上海 200092; 2 杭州市市政设施监管中心,杭州 321000)[摘要]基于一栋高层建筑的刚性模型表面压力测量风洞试验数据,分析了高宽比较大且截面为方形的高层建筑横风向风效应的共同特征。得到如下结论:高层建筑横截面为方形时,其横风向风荷载主要由规则性旋涡脱落导致的尾流激励构成,为窄带随机激励;当高层建筑的高宽比较大时,基阶固有频率相对较低;当高层建筑兼具方形截面和大高宽比这两个特征时,其基阶固有频率可能接近其尾流的旋涡脱落频率,从而发生剧烈的横风向涡激共振。建筑结构截面的小幅增大可使这种剧烈的横风向涡激共振得到有效控制。上部外形的适当处理,也可能有效降低高层建筑的横风向等效风荷载。低矮群楼的出现将在一定程度上影响高层建筑的风荷载。[关键词]高层建筑;风荷载;风效应;横风向Across-wind loads and responses of square high-rise buildings with large aspect ratiosQuan Yong1, Chen Bin2, Gu Ming1(1 State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China;2 Hangzhou Municipal Installation Supervision and Administration Center, Hangzhou 312000, China)Abstract:Based on pressure measurement wind tunnel test data of a real high-rise building, the common aspects of across-wind loads and responses of square high-rise buildings with large aspect ratios are analyzed. The calculated results indicate that the across-wind loads of high-rise buildings with square sections are induced mainly by vortex shedding and are narrow-band random processes. The basic natural frequency of high-rise buildings with large aspect ratios should be low. When a high-rise building has square section and large aspect ratio, it is prone to large across-wind response. A little enlarging of the building section can suppress the large across-wind vortex-induced resonance. The appropriate treatment of the building shape at its upper part may also reduce the across-wind loads effectively. The emergence of low surrounding buildings will affect wind loads in a certain extent.Keywords:high-rise building; wind loads; wind-induced response; across-wind*上海市浦江人才计划项目(08PJ14095);国家自然科学基金项目(50878159,90715040,50321003)。作者简介:全涌,博士,副教授,Email: quanyong@tongji.edu.cn。参考文献[1]张相庭. 结构风压和风振计算[M]. 上海:同济大学出版社,1985.[2]周印. 高层建筑静力等效风荷载和响应的理论与实验研究[D]. 上海:同济大学,1998.[3]ZHOU Y, GU M, XIANG H F. Alongwind static equivalent wind loads and responses of tall buildings. Part Ⅰ: Unfavorable distributions of static equivalent wind loads[J]. Journal of Wind Engineering and Industrial Aerodynamics, 1999,79(1):135-150.[4]ZHOU Y, GU M, XIANG H F. Alongwind static equivalent wind loads and responses of tall buildings. Part Ⅱ: Effects of mode shapes[J]. Journal of Wind Engineering and Industrial Aerodynamics,1999,79(1):151-158.[5]ZHOU Y, KAREEM A, GU M. Gust loading factors for design applications[C]//Wind Engineering into the 21st Century,Larsen, Larose & Livesey,1999:169-176.[6]ZHOU Y, KAREEM A. Gust loading factor: new model[J]. Journal of Structural Engineering, 2001, 127(2): 168-175.[7]ASCE/SEI 7-05 Minimum Design Loads for Buildings and Other Structures[S]. American Society of Civil Engineers,2006.[8]全涌,顾明.高层建筑横风向风致响应及等效静力风荷载的分析方法[J]. 工程力学,2006,23(9):84-89.[9]QUAN Y, GU M,TAMURA Y. Experimental evaluation of aerodynamic damping of square super high-rise buildings[J]. Wind & Structure,2005,8(5):301-324.[10]全涌,顾明,田村幸雄. 方形截面高层建筑横风向等效静力风荷载及加速度响应计算方法[J]. 工程力学,2004(S3):104-110.[11]全涌,顾明. 方形断面高层建筑的气动阻尼[J].工程力学,2004, 21(1): 2