基于空耦表面波-空耦冲击回波法的高铁无砟轨道板脱空检测试验研究  

Experimental study on detachment detection of ballastless track slab of high-speed railway based on air-coupled impact echo and air-coupled surface wave method

作　　者：肖军华[1] 潘越 刘孟波 李航 龙许友 苏志鹏 Xiao Junhua;Pan Yue;Liu Mengbo;Li Hang;Long Xuyou;Su Zhipeng(Key Laboratory of Road and Traffic Engineering of the Ministryof Education,Tongji University,Shanghai 201804,China;China Railway Design Group Co.,Ltd.,Tianjin 300308,China)

机构地区：[1]同济大学道路与交通工程教育部重点实验室,上海201804 [2]中国铁路设计集团有限公司,天津300308

出　　处：《土木工程学报》2024年第11期70-80,128,共12页China Civil Engineering Journal

基　　金：国家重点研发计划项目(2022YFB2602200);上海市科委科技创新行动计划(21DZ1203602);上海市“超级博士后”计划(2022553)。

摘　　要：高速铁路无砟轨道板脱空病害频发,严重影响列车运行安全。为了实现无砟轨道板的快速检测,文章研究联合空耦冲击回波和空耦表面波2种检测方法,以预设轨道板脱空的CRTSⅡ型无砟轨道板为研究对象,通过足尺检测试验,分析冲击荷载作用下轨道板脱空的声频信号特征,构建轨道板脱空指标,实现轨道板脱空平面成像。研究结果表明:当轨道板脱空时,空耦表面波法测得相位谱在第2个相位循环5~10kHz内出现相位不连续现象,频散曲线在波长0.2m左右出现间断;空耦冲击回波法测得声频信号频域图在9960Hz附近出现共振峰,对应的脱空指标值大于0.93,当轨道板与砂浆层接触效果较好,脱空指标值小于0.93。联合空耦表面波法和空耦冲击回波法,实现CRTSⅡ型无砟轨道板脱空的快速连续检测成像。Frequent occurrences of detachment defects in ballastless track slab of high-speed railway severely affect the operation safety of train.To enable rapid detection of detachments in ballastless track slabs,a combination of the air-coupled impact echo and air-coupled surface wave methods is studied.With the CRTS II ballastless track with pre-set detachment defects taken as the research object,full-scale tests were carried out to analyze the acoustic signal characteristics of the track slab detachment under impact loads.A detachment index was developed to facilitate planar imaging of the detachment defects.The research findings indicate that the air-coupled surface wave method result in phase discontinuities in the second phase cycle within 5~10 kHz when detachments of the track slab are present.The interruption of dispersion curve occurs at a wavelength of approximately O.2 m.The air-coupled impact echo method reveals the resonance peak in the frequency domain of around 9960 Hz,which corresponds to the detachment index values greater than 0.93.When the track slab is in good contact with the mortar layer,the detachment index value is smaller than 0.93.By combining the air-coupled surface wave and air-coupled impact echo methods,rapid and continuous detection imaging of detachment defects in CRTS II ballastless track slab can be achieved.

关 键 词：无砟轨道板脱空 空耦冲击回波 空耦表面波 联合检测 脱空成像 

分 类 号：U216[交通运输工程—道路与铁道工程] U216.3