| As the mass construction of highway develops rapidly, the ground penetrating radar (GPR) has been widely applied to highway tunnel tests. As a high-performance, advanced non-destructive testing methods, the GPR can continuously scan the tunnel lining, access to the image of intuitive graphical detection. In the practical use of the GPR, however, there are some differences on judging the radar images due to the noise caused by the strong surface reflection wave and other interference factors, as well as individual knowledge and understanding. It even brings about the deflection of the judging results from the actual test results.The GPR technology is based on the electromagnetic theory. The propagating laws of electromagnetic wave are the theoretical basis for the analysis of experimental data. The reasonable setting of radar parameters are the premise of the radar data. Proficient grasp of the radar data processing and waveform characteristics of radar images is an important way to enhance the ability of recognizing targets.According to the different wave characteristics present in the radar image led by the electromagnetic wave through different medium such as the road tunnel lining,rock,steel and other geotechnical properties, and combining with the actual geological data and design information, the thesis makes judgments about the location and thickness of Highway tunnel lining, the number and distribution of steel bars, as well as the location and type of defects, and also carries out quantitative analysis to the radar images that obtained in the actual testing.The research shows that people can determine the position of the deep reinforced bars by Attenuation compensation gain. After reset the tunnel velocity in the empty water region, the results of analysis are very close to the position of the actual excavation. This firmly proves the fact that the GPR can be used to detect the tunnel lining with good accuracy.
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