摘要
在哈密顿原理的基础上,推导综合考虑剪切变形、层间脱空影响的轨道-桥梁系统自由振动控制微分方程及边界条件,提出轨道-桥梁系统自振频率计算方法。基于本文所提计算方法,讨论轨道-桥梁系统弯曲刚度、砂浆层竖向、纵向刚度、脱空位置以及脱空长度对轨道-桥梁系统自振频率的影响规律。研究结果表明:轨道-桥梁系统固有频率对桥梁层抗弯刚度变化更为敏感;砂浆层纵向刚度和离缝位置变化对轨道-桥梁系统自振频率影响不明显,层间竖向刚度对系统自振频率影响显著;脱空长度变化对轨道-桥梁系统4-5阶固有频率影响更明显,受脱空影响的轨道-桥梁系统自振频率范围随脱空长度增大而增大。
Based on Hamilton’s principle, the differential equations of free vibration of track-bridge systems with mortar gap are derived. Hence, a method for calculating the natural frequencies of track-bridge systems is proposed. The influence of the flexural stiffness of the track-bridge system, the vertical and longitudinal stiffness of the mortar layer,gap position and gap length on the natural frequencies of a track-bridge system is discussed. The results show that the natural frequencies of the track-bridge system are more sensitive to the change of the flexural stiffness of the bridge layer. The change of the longitudinal stiffness of the mortar layer and gap position has no obvious effect on the trackbridge system’s natural frequencies, while the interlayer vertical stiffness has a larger impact. The gap length has a more significant effect on the 4th-5th order natural frequencies of the track-bridge system. The range of the natural frequencies that are affected by the gap widens as the gap length increases.
作者
刘韶辉
蒋丽忠
周旺保
冯玉林
LIU Shao-hui;JIANG Li-zhong;ZHOU Wang-bao;FENG Yu-lin(School of Civil Engineering,Central South University,Changsha 410075,China;National Engineering Research Center of High-speed Railway Construction Technology,Changsha 410075,China;School of Civil Engineering and Architecture East China Jiaotong University,Nanchang 33013,China)
基金
Projects(U1934207,52078487,51778630) supported by the National Natural Science Foundation of China
Project(502501006) supported by the Fundamental Research Funds for the Central Universities,China
Project(2019RS3009)supported by the Hunan Innovative Provincial Construction Project,China
Projects(HJGZ20211003,HJGZ20212009)supported by State Key Laboratory of Performance Monitoring and Protecting of Rail Transit Infrastructure,China。