Application of ground penetrating radar on the void-detection in levee

A series of known buried voids of different sizes and shapes within model sand boxes were constructed. GPR tests were performed to detect and acquire the patterns of images and characteristics signified by the radar signals. The patterns were then used in the field detection of voids in levees to evaluate the applicability of the signal reading. Experiment conducted in the laboratory showed that through the tuning of the frequency sent out by the ground-penetrating radar, voids with diameter larger than 20 cm can be effectively detected. A similar phenomenon of multiple reflections on void-detecting radar image was observed both in the actual levee detection and the model sand box detection. The results show that of the GPR technique can be effectively used to detect the underground voids in the levee.