基于振型动能法的大跨度斜拉桥振型分析和模态识别
|
摘要
针对拉索的自身振型以及与塔梁相互间的模态耦合作用被人为忽略和单凭振型图难以识别出主梁的主振型两大问题,采用多段索单元模拟拉索以便能准确地计算结构模型。通过动力计算分析振型参与的动能比例,实现了振型识别功能,得出斜拉桥的自振频率和振型。分析结果表明:斜拉桥的自振特性表现出明显的三维性和相互耦合的特点,主梁、桥塔、斜拉索之间相互影响;在一个较宽的频率范围内,许多振型都可能被动力荷载激起强烈的振动;为识别出主梁振动为主的振型和主振型方向分析振型参与的动能比例,应采用10阶以上的振型情况分析,为动力测试提供理论数据。
Aiming at two problems that the coupling action of the cable with tower and girder is neglected and the mode shape of girder are difficult to be identified only from the mode shape curve,the multi-cable element was adopted to simulate the cable in order to calculate the dynamic characteristics more exactly.By analyzing the proportion of kinetic energy in each mode shape,the mode shape was identified,the natural vibration frequencies and mode shape of the cable-stayed bridge were obtained.The result enunciates that(1) the dynamic characteristics of cable-stayed bridge are three-dimensional and coupled with each other;(2) many mode shapes can be triggered by dynamic loads in a wide frequency range;(3) in order to recognize the mode shape of girder and the proportion of kinetic energy in each mode shape,tenth and above order mode shapes must be used to provide the calculation data for the dynamic test.
Aiming at two problems that the coupling action of the cable with tower and girder is neglected and the mode shape of girder are difficult to be identified only from the mode shape curve,the multi-cable element was adopted to simulate the cable in order to calculate the dynamic characteristics more exactly.By analyzing the proportion of kinetic energy in each mode shape,the mode shape was identified,the natural vibration frequencies and mode shape of the cable-stayed bridge were obtained.The result enunciates that(1) the dynamic characteristics of cable-stayed bridge are three-dimensional and coupled with each other;(2) many mode shapes can be triggered by dynamic loads in a wide frequency range;(3) in order to recognize the mode shape of girder and the proportion of kinetic energy in each mode shape,tenth and above order mode shapes must be used to provide the calculation data for the dynamic test.
引文
[1]范立础.桥梁抗震[M].上海:同济大学出版社,2001.FAN Li-chu.Earthquake Proof of Bridge[M].Shanghai:TongjiUniversity Press,2001.
[2]汪志刚,孙炳楠.斜拉桥参数振动引起的拉索大幅振动[J].工程力学,2001,18(1):103-109.WANG Zhi-gang,SUN Bing-nan.Cable Vibration of CableStayed Bridge by Parametic Response[J].Engineering Me-chanics,2001,18(1):103-109.
[3]陈水生,孙炳楠.斜拉桥索-桥耦合非线性参数振动数值研究[J].土木工程学报,2003,36(4):70-75.CHEN Shui-sheng,SUN Bing-nan.Numerical Study on NonlinearParametic Vibration of Coupled Cables and Bridge Decks[J].China Civil Engineering Journal,2003,36(4):70-75.
[4]汪志刚,孙炳楠.斜拉桥的参数振动[J].土木工程学报,2002,35(5):28-33.WANG Zhi-gang,SUN Bing-nan.Parametic Vibration of theCable in Cable-stayed Bridge[J].China Civil EngineeringJournal,2002,35(5):28-33.
[5]亢战,钟万勰.斜拉桥参数共振问题的数值研究[J].土木工程学报,1998,31(4):14-22.KANG Zhan,ZHONG Wan-xie.Numerical Study on ParameticResonance of Cable in Cable-stayed Bridge[J].China CivilEngineering Journal,1998,31(4):14-22.
[6]王新忠,周水兴,刘琪.独塔单索面斜拉桥动力特性分析[J].重庆交通学院学报,2007,26(3):10-13.WANG Xin-zhong,ZHOU Shui-xing,LIU Qi.Dynamic Char-acteristic Analysis of Single-column Pylon of Single-cable-planeCable-stayed Bridge[J].Journal of Chongqing Jiaotong Uni-versity,2007,26(3):10-13.
[7]余报楚,张哲,朱巍志,等.大跨度斜拉桥与T构协作体系的动力特性分析[J].公路交通科技,2007,24(4):84-89.YU Bao-chu,ZHANG Zhe,ZHU Wei-zhi,et al.Analysis ofDynamic Characteristics of Collaborated System with Long-spanCable-stayed Bridge and T-shape Rigid Structure[J].Journalof Highway and Transportation Research and Development,2007,24(4):84-89.
[8]孙正华,李兆霞.润扬斜拉桥有限元模拟及模态分析[J].地震工程与工程振动,2006,26(2):25-32.SUN Zheng-hua,LI Zhao-xia.Finite Element Modeling andModal Analysis of Runyang Cable-stayed Bridge[J].Earthquake Engineering and Engineering Vibration,2006,26(2):25-32.
[9]张浩,陈应波.大跨度斜拉桥模态测试与分析[J].武汉理工大学学报,2007,29(4)79-81.ZHANG Hao,CHEN Ying-bo.Modal Test and Analysis of Long-span Cable-stayed Bridge[J].Journal of Wuhan University ofTechnology,2007,29(4)79-81.
[2]汪志刚,孙炳楠.斜拉桥参数振动引起的拉索大幅振动[J].工程力学,2001,18(1):103-109.WANG Zhi-gang,SUN Bing-nan.Cable Vibration of CableStayed Bridge by Parametic Response[J].Engineering Me-chanics,2001,18(1):103-109.
[3]陈水生,孙炳楠.斜拉桥索-桥耦合非线性参数振动数值研究[J].土木工程学报,2003,36(4):70-75.CHEN Shui-sheng,SUN Bing-nan.Numerical Study on NonlinearParametic Vibration of Coupled Cables and Bridge Decks[J].China Civil Engineering Journal,2003,36(4):70-75.
[4]汪志刚,孙炳楠.斜拉桥的参数振动[J].土木工程学报,2002,35(5):28-33.WANG Zhi-gang,SUN Bing-nan.Parametic Vibration of theCable in Cable-stayed Bridge[J].China Civil EngineeringJournal,2002,35(5):28-33.
[5]亢战,钟万勰.斜拉桥参数共振问题的数值研究[J].土木工程学报,1998,31(4):14-22.KANG Zhan,ZHONG Wan-xie.Numerical Study on ParameticResonance of Cable in Cable-stayed Bridge[J].China CivilEngineering Journal,1998,31(4):14-22.
[6]王新忠,周水兴,刘琪.独塔单索面斜拉桥动力特性分析[J].重庆交通学院学报,2007,26(3):10-13.WANG Xin-zhong,ZHOU Shui-xing,LIU Qi.Dynamic Char-acteristic Analysis of Single-column Pylon of Single-cable-planeCable-stayed Bridge[J].Journal of Chongqing Jiaotong Uni-versity,2007,26(3):10-13.
[7]余报楚,张哲,朱巍志,等.大跨度斜拉桥与T构协作体系的动力特性分析[J].公路交通科技,2007,24(4):84-89.YU Bao-chu,ZHANG Zhe,ZHU Wei-zhi,et al.Analysis ofDynamic Characteristics of Collaborated System with Long-spanCable-stayed Bridge and T-shape Rigid Structure[J].Journalof Highway and Transportation Research and Development,2007,24(4):84-89.
[8]孙正华,李兆霞.润扬斜拉桥有限元模拟及模态分析[J].地震工程与工程振动,2006,26(2):25-32.SUN Zheng-hua,LI Zhao-xia.Finite Element Modeling andModal Analysis of Runyang Cable-stayed Bridge[J].Earthquake Engineering and Engineering Vibration,2006,26(2):25-32.
[9]张浩,陈应波.大跨度斜拉桥模态测试与分析[J].武汉理工大学学报,2007,29(4)79-81.ZHANG Hao,CHEN Ying-bo.Modal Test and Analysis of Long-span Cable-stayed Bridge[J].Journal of Wuhan University ofTechnology,2007,29(4)79-81.
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