Ke Ying Tzu, Cheng Chia-Chi, Lin Yung-Chiang, Ni Yi-Qing, Hsu Keng-Tsang, Wai Tai-Tung
Department of Construction Engineering, Chaoyang University of Technology, Wufeng 413310, Taiwan.
Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hun Hom, Kowloon, Hong Kong.
Sensors (Basel). 2020 May 26;20(11):3022. doi: 10.3390/s20113022.
The severe deterioration of a cement asphalt (CA) mortar layer may lead to the movement of the upper concrete slab and impair the safety of the speedy train. In this study, a test specimen simulating the structure of high-speed rail track slabs was embedded with delaminated cracks in various lateral sizes inside the CA mortar layer. Impact-echo tests (IE) were performed above the flawed and flawless locations. In present study, the IE method is chosen to assess defects in the CA mortar layer. Both traditional IE and normalized IE are used for data interpolation. The normalized IE are the simulated transfer function of the original IE response. The peak amplitudes in the normalized amplitude spectrum and the peak frequency in the traditional amplitude spectrum for the top concrete overlay were used to develop simple indicators for identifying the integrity of the CA mortar layer. The index was based on the difference of the experimental peak amplitude and frequency of the ones calculated from previously developed formulas for plates without substrates. As a result, the technique does not require an experimental baseline for the crack assessment. A field test and analysis procedure for evaluating high-speed rail slab systems are proposed.
水泥沥青（CA）砂浆层的严重劣化可能会导致上部混凝土板的移动，并损害高速列车的安全性。在本研究中，一个模拟高速铁路轨道板结构的试件在CA砂浆层内部嵌入了不同横向尺寸的分层裂缝。在有缺陷和无缺陷的位置上方进行了冲击回波测试（IE）。在本研究中，选择IE方法来评估CA砂浆层中的缺陷。传统IE和归一化IE都用于数据插值。归一化IE是原始IE响应的模拟传递函数。顶部混凝土覆盖层的归一化振幅谱中的峰值振幅和传统振幅谱中的峰值频率被用于开发识别CA砂浆层完整性的简单指标。该指标基于实验峰值振幅与根据先前为无基层板开发的公式计算出的峰值振幅和频率之间的差异。结果，该技术在裂缝评估中不需要实验基线。提出了一种评估高速铁路轨道板系统的现场测试和分析程序。
