In order to monitor the rail base, the dispersion characteristics and propagation properties of the guided wave are studied. Firstly, two modes named as Modes V₁ and V₂ are selected by the semianalytical finite element method (SAFE). The region at the bottom edge can be monitored by Mode V₁, while the junction of the base edge and the flange can be detected by Mode V₂. Then, the characteristics in the propagation process are analyzed using the finite element method (FEM). The two modes can be separated about 0.6 ms after they are excited. Thirdly, a wave attenuation algorithm based on mean is proposed to quantify the wave attenuation. Both waves can have weak attenuation and be detected within 5 m. Finally, a mode-identified experiment is performed to validate the aforementioned analysis. And a defect detection experiment is performed to demonstrate the excellent monitoring characteristics using Mode V₂. These results can be used to monitor the rail base in practice engineering.

中文翻译：

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导波传播，用于监视铁路基地

为了监测轨道基础，研究了导波的色散特性和传播特性。首先，通过半解析有限元方法（SAFE）选择两个名为模式V ₁和V _2的模式。底部边缘的区域可以通过模式V ₁监视，而基础边缘和法兰的接合点可以通过模式V ₂进行检测。。然后，使用有限元方法（FEM）分析传播过程中的特性。两种模式在激发后可以分开约0.6 ms。第三，提出了一种基于均值的波衰减算法来量化波衰减。这两个波的衰减都较弱，并且在5 m以内被检测到。最后，进行模式识别实验以验证上述分析。并进行了缺陷检测实验，以展示使用模式V ₂的出色监视特性。这些结果可用于在实践工程中监视铁路基地。