Study on Underground Cavity Detection by Ground Penetrating Radar

Through analyzing the electromagnetic wave propagation in underground medium, this paper introduces the basic principle of detecting the underground cavity by Ground Penetrating Radar (GPR). Doing experiments with different cavity models, the characteristics of the reflection spectrum about the cavity can be understood. Contrast the differences of the detecting waveform between different models and verify the practicability of research findings sites detecting. The image recognition rules of underground cavity in radar spectrum are summarized. It provides theoretical support for the detection and the damage assessment, and is very effective in disaster prevention and reduction.