| Recent multi-channel ground-penetrating radar (GPR) provides survey data under paved roads with high density. In order to keep high scanning speed, intervals between faces of antennas and roads have frequently some distance, which supplies multiple reflections on radar records. We acquired multi-channel GPR records with GNSS measurements on a round test road in PWRI using two GPR equipment designed with a ground coupled type. Our multi-channel records include little noise of multiple reflections and we can clearly identify boundaries of underground road constructions. It also includes records with different offsets and we can estimate RMS velocities for target boundaries. NMO correction was applied for all GPR data using estimated velocities. Reflections from buried pipes and boundaries of road structures are clearly identified in a depth slice section. |
