Application of spectral energy algorithm based on the GPR reflected wave for detecting underground area

Abstract The surface subsidence and collapse which caused by abandoned and remnant underground area affects engineering construction seriously. In order to avoid disaster caused by ground collapse, it is obviously important to find out the depth and distribution range about underground area. Ground Penetrating Radar (GPR) is as a fast and non-destructive detecting technology, and the unshielded antenna with low frequency had been used to detect the shallow underground area which can be distinguished from the underground area with larger-scale and significant differences, but conventional data processing method is difficult to identify the weak useful signal, and also will cause uncertainty for abnormal interpretation. Based on the unique feature of spectral response for the single medium, spectral energy algorithm has been used for processing data about GPR reflected wave in this article. The spectral response feature of air medium has been extract from the signal of radar reflected wave, the spectral energy strength about air medium has been calculated, and the feature of space distribution about underground area has been inversed by three-dimensional reconstruction. The results are basically consistent with this method through validating by high-density resistivity method, and prove that this data processing technology is effective and precise. It provides scientific basis for the construction engineering to implement successfully.