城市轨道交通箱梁中高频导波特性分析  

Mid-and high-frequency wave characteristics of a rail transit box-girder bridge

作　　者：宋立忠 郭敏 王欣欣 李小珍[1] SONG Lizhong;GUO Min;WANG Xinxin;LI Xiaozhen(Department of Bridge Engineering,Southwest Jiaotong University,Chengdu 610031,China;Engineering Research Center of Railway Environment Vibration and Noise,Ministry of Education,East China Jiaotong University,Nanchang 330013,China;Guangzhou Metro Design&Research Institute Co.,Ltd.,Guangzhou 510010,China)

机构地区：[1]西南交通大学桥梁工程系,成都610031 [2]华东交通大学铁路环境振动与噪声教育部工程研究中心,南昌330013 [3]广州地铁设计研究院股份有限公司,广州510010

出　　处：《振动与冲击》2019年第18期207-214,共8页Journal of Vibration and Shock

基　　金：国家自然科学基金(51878565;51778534)

摘　　要：采用传统有限元法、波导有限元法结合现场锤击试验研究了城市轨道交通混凝土箱梁的中高频振动特性,分析了箱梁中导波的频散特性及其对箱梁中高频振动特性的影响。以广州地铁四号线30 m混凝土简支箱梁为研究对象,开展了现场锤击试验;使用传统有限元软件ANSYS建立了箱梁的有限元模型,并通过对比箱梁导纳计算结果和实测结果验证了有限元模型的可靠性;使用Matlab编程对箱梁进行波导有限元分析,得到了箱梁中导波的频散特性和导波模态,并讨论了引起箱梁中高频振动峰值的导波类型。研究结果表明:顶板导纳的优势频段约为80~120 Hz,底板导纳的优势频段约为60~120 Hz;在120 Hz以内,箱梁中共出现了9种导波模态,其中竖向弯曲波E和H是引起箱梁中高频振动峰值的主要导波类型。The mid-and high-frequency vibration characteristics of a rail transit box-girder bridge was investigated based on the conventional finite element(FE)method,waveguide finite element(WFE)method and hammer excitation test.The dispersion characteristics of the waves propagating in the box-girder and their influences on the mid-and high-frequency vibration characteristics of the box-girder were analyzed.First,a hammer excitation test was carried out on the 30m-length simply-supported box-girder of Guangzhou Metro Line 4.Then,a FE model was established by using ANSYS and the results were verified by comparing the calculated and measured mobilities.Finally,a program based on WFE method written in Matlab was used to obtain the dispersion characteristics and modes of the waves propagating in the box-girder.The dominant wave modes at mobility peak frequencies were also identified.The results show that the predominant frequencies of the top and bottom slab mobilities range from 80 to 120 Hz and 60 to 120 Hz respectively.In total 9 wave modes propagate in the box-girder below 120 Hz.The vertical flexural waves E and H are the dominant waves that induce the mid-and high-frequency vibration peaks of the box-girder.

关 键 词：简支箱梁 中高频振动 导波 波导有限元法(WFE) 导纳 

分 类 号：U24[交通运输工程—道路与铁道工程] TB123[理学—工程力学]