摘要
为研究不同跨度高速铁路简支箱梁在列车作用下的动力性能,以郑济高铁40 m简支箱梁和京沪高铁32 m简支箱梁为背景,研究40 m和32 m简支箱梁共振条件;采用多体动力学和有限元相结合的方法建立车-轨-桥耦合振动模型,对比分析列车以不同运行速度通过40 m和32 m简支箱梁时的动力系数、竖向和横向加速度、竖向位移等振动响应。结果表明:40 m和32 m简支箱梁的共振速度分别为428.5 km/h和517.8 km/h,在我国目前高速铁路的列车运行速度下,箱梁不会发生一阶共振响应,但会出现二阶与三阶超谐共振以及三阶消振现象;2种箱梁的挠度动力系数均小于运营动力系数,且挠度动力系数与列车运行速度成正相关;在相同工况下,40 m简支箱梁上的竖向振动和跨中竖向位移幅值大于32 m简支箱梁,但横向振动更小;在不产生共振消振情况下,列车通过速度越快,箱梁竖向位移越大,但由于2种箱梁的截面尺寸、跨径不同,使得2种箱梁的挠跨比差值很小。在现有列车运行速度条件下,可推广使用40 m简支箱梁。
This paper studies the dynamic performance of high-speed railway simply-supported box girder of varying span lengths under train loads.Based on the bridges of Zhengzhou-Jinan High-speed Railway bridges(involving 40 m-long spans)and the Beijing-Shanghai High-speed Railway bridges(involving 32 m-long spans),the factors inducing resonant vibrations of the 40 m-and 32 m-long simply-supported box girders were studied.The train-track-bridge coupling vibrations were studied by numerical simulations and multi-body dynamics simulation.Parameters,including dynamic coefficient,vertical and transverse accelerations and vertical displacements of the 40 m-and 32 m-long simply-supported box girders were analyzed at different train traveling speeds.It is shown that the 40 m-and 32 m-long simply-supported box girders will be subject to first-mode resonant vibrations at a train traveling speed of 428.5 km/h and 517.8 km/h,respectively,indicating that the box girders of the existing high-speed railway bridges in China won′t undergo resonant vibrations under the current train traveling speeds,but will be subject to second-mode and third-mode superharmonic resonance and third-mode vibration attenuation.The deflection dynamic coefficients of the two types of box girders are smaller than the dynamic coefficients at the service state,and the deflection dynamic coefficient is in linear relation with the train traveling speed.Under the same loading condition,the vertical vibrations and mid-span vertical displacement range of the 40 m-long simply-supported girder are stronger than those in the 32 m-long simply-supported girder,but with smaller transverse vibrations.Without vibration attenuation,the faster the train speed,the larger the vertical displacement of the box girder.Due to the different cross-sectional sizes and span lengths,the difference between the deflection-span ratios of the two types of girders is minimal.The 40 m-long simply-supported box girder is a better choice for the high-speed railway bridges allowing the currently-required train traveling speeds.
作者
罗锟
王凯新
甄慧杰
帅蔚晨
LUO Kun;WANG Kaixin;ZHEN HuiJie;SHUAI Weichen(Engineering Research Center of Railway Environmental Vibration and Noise,Ministry of Education,East China Jiaotong University,Nanchang 330013,China;State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure,East China Jiaotong University,Nanchang 330013,China)
出处
《桥梁建设》
北大核心
2025年第1期49-55,共7页
Bridge Construction
基金
国家自然科学基金项目(52178424,51868023)
江西省自然科学基金重点项目(20224ACB204018)。
关键词
铁路桥
简支箱梁
列车运行速度
共振
动力系数
加速度
位移
有限元法
railway bridge
simply-supported box girder
train traveling speed
resonant vibration
dynamic coefficient
acceleration
displacement
finite element method
