At Quadra Utility Locating Ltd., we use some of the most state-of-the-art utility locating tools on the market. Some key equipment technologies are listed below:
GROUND PENETRATING RADAR
Used largely to locate non-metallic pipes, the GPR is an essential tool in the locator's toolbox.
Ground Penetrating Radar (GPR) uses high frequency radio signals transmitted into the ground with reflected signals returned to the receiver, interpreted by the unit and displayed in a visual format (i.e. LCD screen panel). on-board measures the time taken for a pulse to travel to and from the target which indicates its depth and location.
The common “lawnmower” style of GPR unit is used for utility locating in subsurface soils (125 MHz to 370 MHz). A higher frequency GPR unit is required to locate rebar, conduits and post-tension cables imbedded in concrete.
Different soil types, soil geochemistry and object depths all produce different exploration depths for a GPR unit. Generally, sands and gravels and bedrock produce a depth range much deeper than sea water, concrete (highly conductive material) or clays.
To locate objects such as rebar, conduits and post-tension cables imbedded in concrete a high frequency Concrete Scanning GPR system is used (read below).
To locate objects such as rebar, conduits and post-tension cables imbedded in concrete a high frequency GPR system is used (1,000 MHz). The data is collected in grid pattern line scans to map slab anomalies and create a 3D picture of the slab.
Quadra operates a fleet of concrete scanning equipment and is ready to use our equipment on your next residential development, commercial development, bridge work or subslab assessment project.
The newest tool in the concrete scanning toolbox is a Ferroscan system, perfect for scans of large areas of concrete quickly and easily. Provides accurate depth of cover measurements for reinforcement (rebar) at depths of up to 4 in (100 mm). Displays a clear 2D image of the reinforcement on the monitor for on-the-spot structural analysis and depth of cover assessment. Records scan data automatically over lengths of up to 30 meters and up to 9 Imagescans. Perfect for Rebar verification and analysis, checking concrete cover over large areas for structural repair work, building acceptance inspections and quality control, helps avoid costly rebar hits and damage caused by cutting through structurally significant reinforcement when coring and hammer drilling, generation of structural assessement reports including statistics and visual presentation in 2D/3D views of areas of up to 45x45 m.
ELECTROMAGNETIC (EM) LOCATING
The electromagnetic (EM) scanning tools are used to locate objects using single or multi-frequencies.EM utility locators are commonly used for tracing metallic pipes and utility cables consisting of a separate transmitter and receiver. The transmitter emits a radio frequency EM field that induces secondary fields in nearby metallic pipes and cables. The receiver detects these fields and accurately locates and traces the pipes or conduits. Another approach is to sweep areas for 60 Hz signal emanating from electrical lines.