探地雷达对路面板脱空现象检测时的信号分析与处理

基于探地雷达对水泥混凝土路面板探测原理,推导出当路面板下出现脱空时反射波传播发生变化的时差公式。分析路用探地雷达检测时的回波信号,针对由于噪声而出现的各种杂波信号,提出滤波处理方法,保留有用的回波信号。利用小波分析方法,对山东烟台—威海高速公路试验段探地雷达实地检测所得信号进行分析,剔除各种误差,以准确测得脱空厚度。结果表明,采用探地雷达方法具有快速、无损、精度高等优点。

Signal Analysis and Processing for Detecting Void Phenomenon under Concrete Pavement by Using Ground Penetrating Radar

Based on detection principle of ground penetrating radar for cement concrete pavement,the time difference formula of the reflection wave change when the voids occurring under pavement was derived. The echo signals of pavement ground penetrating radar detection were analysed. For a variety of clutter signals arose from noises,filtering approach was proposed to retain useful echo signals. By using wavelet analysis method,the field detected signals from the test section of Yantai-Weihai expressway in Shandong Province with ground penetrating radar were analysed,and all kinds of error were eliminated to accurately measure the thickness of voids. The result shows that the detecting method using ground penetrating radar is rapid,non-destructive and precise.