Ground Penetrating Radar (GPR)

Ground penetrating radar (GPR) employs radio waves, typically in the 100MHz to 1.5 GHz frequency range, to map the internal structure of materials. Electromagnetic waves propagate into the subsurface via the radar antenna and reflect off objects or boundaries with differing dielectric permittivity and electrical conductivity than the host material. Materials with a high contrast in permittivity such as soil/air, concrete/soil, and steel/soil, allow for detection of these changes.  Vertical structures such as walls and columns can also be evaluated using GPR. A variety of radar antennas are available to target dimensions for optimum detection and imaging.

GPR applications are utilized to evaluate:

• Buried pipelines, underground storage tanks, power lines, backfilled trenches, and large voids
• Rebar/post-tension cable location
• Non-destructive testing of asphalt and concrete
• Existing bridge deck conditions
• Runway and taxiway conditions
• Pavement and subgrade conditions
• Utility line locations
• Archeological locating
• Abandoned mines
• Tunnels
• Some gunite or shotcrete structures