Ground Penetrating Radar

Applications

Ground penetrating radar (GPR) provides a high resolution, cross-sectional image of the shallow subsurface. A short pulse of electromagnetic energy is radiated downward. When this pulse strikes an interface between layers of material with different electrical properties, part of the wave reflects back, and the remaining energy continues to the next interface. Depth measurements to interfaces are determined from travel time of the reflected pulse and the velocity of the radar signal.

The Ground Penetrating Radar (GPR) method relies on contrasts in the dielectric constant between materials. The methods have been used extensively to:

General Applications

  • Void Mapping - Thin Voids
    Tool: High frequency antennas such as 800MHz, 1000 MHz, 1600MHz 2600MHz
    Description Commonly used to map thin voids under slabs as little as 2 cm thick. It is very good at mapping the lateral extents of voids. It can't measure the thickness of the void very well but it is possible to determine the relative thickness: View Case Study
  • Void Mapping - Moderate Voids
    Tool: Medium sized frequencies such as 270MHz, 300MHz, 400MHz
    Description Commonly used to map voids and soil sloughing in the upper 2 to 5 meters View Case Study
    Distinguish between ufill / voids and sloughing
    View Case Study 1
    View Case Study 2
    View Case Study 3
  • Void Mapping - Larger Voids
    Tool: Lower frequency antennas such as 200 MHz hyperstack, 100MHz, 50 MHz and 25 MHz
    Description Deeper voids from Karst features, mine workings or large utilities from 5 to 30 meters range.
    View Case Study
  • Concrete Delamination
    Tool: High frequency antennas such as 800MHz, 1000 MHz, 1600MHz 2600MHz
    Description Bridge decks or other concrete structures with reinforcing steel.
    View Case Study
  • Concrete Reinforcement & Thickness
    Tool: High frequency antennas such as 800MHz, 1000 MHz, 1600MHz 2600MHz
    Description Location, size and depth of steel. slab thickness.
    View Case Study
  • Sedimentary Layer Mapping
    Tool: Medium sized frequencies and lower frequencies.
    Description Medium sized frequencies and lower frequencies. Mapping areas of fill and ground disturbance. Mapping water table and other geologic contacts. Its possible to distinguish clays/silts versus sands/gravels versus cobbles/boulders.
    View Case Study
  • Environment Site Assessment
    Tool: Medium sized frequencies such as 270MHz, 300MHz, 400MHz.
    Description Mapping former excavation such as former UST locations, abandoned pipes.
  • Utility Mapping & Borehole Clearance
    Tool: Medium sized frequencies such as 270MHz, 300MHz, 400MHz.
    DescriptionThe most common application of GPR. Used for a multitude of private locating companies.
    View Case Study 1
    View Case Study 2
  • Bedrock Mapping
    Tool: Medium sized frequencies and lower frequencies.
    DescriptionUnder the right overburden conditions the top of bedrock can incredibly efficient.
    View Case Study

Technologies

Ground Penetrating Radar Systems
  • StructureScan™ Mini HR
  • UtilityScan® DF &UtilityScan®
  • RoadScan™ 30
  • BridgeScan™