基于反应谱方法的双曲冷却塔地震响应特征分析
|
摘要
为明确冷却塔结构的振型特征、不同振型在地震响应中贡献及地震内力环向分布特点,便于冷却塔结构设计,以某大型双曲冷却塔为例,在动力特性分析基础上采用反应谱方法进行地震响应计算,并与其它荷载作用下内力进行对比。研究表明,冷却塔振型可据其形状、方向分为环向与子午向谐波耦合振型、侧向弯曲振型、竖向伸缩振型及竖向扭转振型4类。第1类振型为冷却塔主振型;水平、竖向地震响应贡献分别来自第2、3类振型,第1、4类振型对地震作用均无贡献。侧弯振型的截面变形特征决定水平地震作用下塔筒内力在环向呈正弦或余弦分布。无论水平或竖向地震作用,塔筒中主要产生双向轴力,在下支柱主要产生轴力及弯矩,且水平地震作用产生的内力远大于竖向地震。较其它荷载作用效应,地震作用对塔筒的关键效应为塔筒中下区段内子午向拉力及塔筒顶端0.2HS范围内环向拉力,且地震效应对下支柱影响明显大于对塔筒影响。
In order to illustrate the features of free vibration modes of hyperboloidal cooling towers( HCTs) and their contributions to seismic responses,response spectral analysis was conducted for a certain HCT and its dynamic feature analysis was done too. Then,latitude distributions of its internal forces were discussed. Comparative study under other load effects was also presented to identify the status of its seismic responses for structure design. It was shown that according to their shapes and directions the modes of the HCT can be classified into four types including coupled modes between latitude and meridian hrmonics,lateral bending modes,vertical stretching modes and vertical torsion modes; the first type is the most dominant,but it has no contributions to seismic responses just like the forth type; the contributions to horizontal and vertical seismic responses all come from the second type and the third one,respectively; all internal forces are in sine or cosine distribution along the latitude direction,depending on the cross section deformations of lateral bending modes; the prominent internal forces in the shell are axial forces in latitude and meridian directions for horizontal or vertical seismic inputs,the corresponding prominent internal forces in columns are axial force and moment; the horizontal seismic responses are much larger than the vertical seismic responses; based on the comparison with other load effects,the key seismic responses for structure design of the shell are the latitude axial force at the top of the shell and the meridian axial force in the lower half shell,and the seismic responses of columns are more significant than those of the shell.
In order to illustrate the features of free vibration modes of hyperboloidal cooling towers( HCTs) and their contributions to seismic responses,response spectral analysis was conducted for a certain HCT and its dynamic feature analysis was done too. Then,latitude distributions of its internal forces were discussed. Comparative study under other load effects was also presented to identify the status of its seismic responses for structure design. It was shown that according to their shapes and directions the modes of the HCT can be classified into four types including coupled modes between latitude and meridian hrmonics,lateral bending modes,vertical stretching modes and vertical torsion modes; the first type is the most dominant,but it has no contributions to seismic responses just like the forth type; the contributions to horizontal and vertical seismic responses all come from the second type and the third one,respectively; all internal forces are in sine or cosine distribution along the latitude direction,depending on the cross section deformations of lateral bending modes; the prominent internal forces in the shell are axial forces in latitude and meridian directions for horizontal or vertical seismic inputs,the corresponding prominent internal forces in columns are axial force and moment; the horizontal seismic responses are much larger than the vertical seismic responses; based on the comparison with other load effects,the key seismic responses for structure design of the shell are the latitude axial force at the top of the shell and the meridian axial force in the lower half shell,and the seismic responses of columns are more significant than those of the shell.
引文
[1]李佳颖,任春玲,黄志龙.自然通风冷却塔的实验及有限元分析[J].力学季刊,2007,28(3):443-447.LI Jia-ying,REN Chun-ling,HUANG Zhi-long.Experiment study and finite element analysis of a natural draft cooling tower[J].Chinese Quarterly of Mechanics,2007,28(3):443-447.
[2]张妍.超大型冷却塔随机地震响应及可靠度分析[D].西安:西安建筑科技大学,2011.
[3]柯世堂,赵林,葛耀君.超大型冷却塔结构风振与地震作用影响比较[J].哈尔滨工业大学学报,2010,42(10):1635-1641.KE Shi-tang,ZHAO Lin,GE Yao-jun.Comparison of superlarge cooling towers under earthquake excitation and wind load[J].Journal of Harbin Institute of Technology,2010,42(10):1635-1641.
[4]陈艳娇.冷却塔模型的抗震计算与试验研究[D].杭州:浙江大学,2008.
[5]薛文,白国良,姚友成,等.超大型双曲冷却塔考虑不同场地类型的地震性能研究[J].水利与建筑工程学报,2010,8(4):224-226.XUE Wen,BAI Guo-liang,YAO You-cheng,et al.Study on seismic performance of large hyperbolic cooling tower in different fields[J].Journal of Water Resources and Architectural Engineering,2010,8(4):224-226.
[6]Wittek U,Lang C.Non-linear earthquake analysis for RC natural draught cooling towers[J].Journal of the International Association for Shell and Spatial Structures,2002,140(43):143-158.
[7]Nasir A M,Thambiratnam D P,Butler D,et al.Dynamics of axisymmetric hyperbolic shell structures[J].Thin-walled Structures,2002,40(7/8):665-690.
[8]Sabouri-Ghomi S,Nik F A,Roufegarinejad A,et al.Numerical study of the nonlinear dynamic behaviour of reinforced concrete cooling towers under earthquake excitation[J].Advances in Structural Engineering,2006,9(3):433-442.
[9]孔麟.超大型间接空冷塔的地震反应分析[D].西安:西安理工大学,2009.
[10]翁旭然,戴君武,胡扬.超大型钢筋混凝土冷却塔模型地震模拟振动台试验研究[J].福州大学学报(自然科学版),2013,41(4):699-703.WENG Xu-ran,DAI Jun-wu,HU Yang.Shaking table test for the 1/30 model of a super huge R/C cooling tower[J].Journal of Fuzhou University(Natural Science Edition),2013,41(4):699-703.
[11]张军锋,葛耀君,赵林.双曲冷却塔结构特性新认识[J].工程力学,2013,30(6):67-76.ZHANG Jun-feng,GE Yao-jun,ZHAO Lin.New perceptions on the structure behavior of hyperboloidal cooling towers[J].Engineering mechanics,2013,30(6):67-76.
[12]GB/T50102-2003,工业循环水冷却设计规范[S].
[13]张军锋,葛耀君,赵林.基于风洞试验的双曲冷却塔静风整体稳定研究[J].工程力学,2012,29(5):68-77.ZHANG Jun-feng,GE Yao-jun,ZHAO Lin.Study on global aerostatic stability of hyperboloidal cooling towers based on the wind tunnel tests[J].Engineering Mechanics,2012,29(5):68-77.
[14]Busch D,Harte R,Niemann H J.Study of a proposed 200m high natural draught cooling tower at power plant Frimmersdorf/Germany[J].Engineering Structures,1998,20(10):920-927.
[15]张军锋,葛耀君.双曲冷却塔温度效应分析[J].华中科技大学学报(自然科学版),2012,40(11):63-67.ZHANG Jun-feng,GE Yao-jun.Study on the thermal effects of hyperboloidal cooling towers[J].Journal of Huazhong University of Science and Technology(Natural Science Edition),2012,40(11):63-67.
[2]张妍.超大型冷却塔随机地震响应及可靠度分析[D].西安:西安建筑科技大学,2011.
[3]柯世堂,赵林,葛耀君.超大型冷却塔结构风振与地震作用影响比较[J].哈尔滨工业大学学报,2010,42(10):1635-1641.KE Shi-tang,ZHAO Lin,GE Yao-jun.Comparison of superlarge cooling towers under earthquake excitation and wind load[J].Journal of Harbin Institute of Technology,2010,42(10):1635-1641.
[4]陈艳娇.冷却塔模型的抗震计算与试验研究[D].杭州:浙江大学,2008.
[5]薛文,白国良,姚友成,等.超大型双曲冷却塔考虑不同场地类型的地震性能研究[J].水利与建筑工程学报,2010,8(4):224-226.XUE Wen,BAI Guo-liang,YAO You-cheng,et al.Study on seismic performance of large hyperbolic cooling tower in different fields[J].Journal of Water Resources and Architectural Engineering,2010,8(4):224-226.
[6]Wittek U,Lang C.Non-linear earthquake analysis for RC natural draught cooling towers[J].Journal of the International Association for Shell and Spatial Structures,2002,140(43):143-158.
[7]Nasir A M,Thambiratnam D P,Butler D,et al.Dynamics of axisymmetric hyperbolic shell structures[J].Thin-walled Structures,2002,40(7/8):665-690.
[8]Sabouri-Ghomi S,Nik F A,Roufegarinejad A,et al.Numerical study of the nonlinear dynamic behaviour of reinforced concrete cooling towers under earthquake excitation[J].Advances in Structural Engineering,2006,9(3):433-442.
[9]孔麟.超大型间接空冷塔的地震反应分析[D].西安:西安理工大学,2009.
[10]翁旭然,戴君武,胡扬.超大型钢筋混凝土冷却塔模型地震模拟振动台试验研究[J].福州大学学报(自然科学版),2013,41(4):699-703.WENG Xu-ran,DAI Jun-wu,HU Yang.Shaking table test for the 1/30 model of a super huge R/C cooling tower[J].Journal of Fuzhou University(Natural Science Edition),2013,41(4):699-703.
[11]张军锋,葛耀君,赵林.双曲冷却塔结构特性新认识[J].工程力学,2013,30(6):67-76.ZHANG Jun-feng,GE Yao-jun,ZHAO Lin.New perceptions on the structure behavior of hyperboloidal cooling towers[J].Engineering mechanics,2013,30(6):67-76.
[12]GB/T50102-2003,工业循环水冷却设计规范[S].
[13]张军锋,葛耀君,赵林.基于风洞试验的双曲冷却塔静风整体稳定研究[J].工程力学,2012,29(5):68-77.ZHANG Jun-feng,GE Yao-jun,ZHAO Lin.Study on global aerostatic stability of hyperboloidal cooling towers based on the wind tunnel tests[J].Engineering Mechanics,2012,29(5):68-77.
[14]Busch D,Harte R,Niemann H J.Study of a proposed 200m high natural draught cooling tower at power plant Frimmersdorf/Germany[J].Engineering Structures,1998,20(10):920-927.
[15]张军锋,葛耀君.双曲冷却塔温度效应分析[J].华中科技大学学报(自然科学版),2012,40(11):63-67.ZHANG Jun-feng,GE Yao-jun.Study on the thermal effects of hyperboloidal cooling towers[J].Journal of Huazhong University of Science and Technology(Natural Science Edition),2012,40(11):63-67.
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心