Determination of the cover thickness over a road gallery

The maintenance of civil engineering structures often requires the verification of existing plans.

In this context, the cover thickness atop a gallery was measured with a double-frequency georadar. This instrument is ideal for the rapid acquisition of high resolution profiles.

The high contrast in electrical permittivity between the concrete of the gallery and the cover material allows the detection of variations in the depth of the gallery below ground level.

GPR profile showing a clear reflector, the top of the road pavement

Variations of the main reflector’s depth (top layer of a road pavement) are visible, as well as a large bump at 70 meters

HiMod GPR designed for civil engineering purposes
Location Switzerland
Instrument RIS HiMod 200-600MHz
Positioning DGPS & odometer
Total length 1000 meter
Personnel 3 people
Duration 0.5 days