Radio frequency waves (0.5 to 2GHz) from radar are transmitted directly into the material. The waves propagate through the material until a boundary of different electrical characteristic is encountered.
A part of the incident energy is reflected and the remainder travels across the boundary at a new velocity. The reflected (echo) wave is picked up by a receiver. The transducer is drawn over a surface and forms a continuous profile of the material condition below. The equipment consists of a radar console, a graphic scanning recorder and a combined transmitting and receiving transducer.
It is capable of detecting and evaluating a number of parameters in reinforced concrete structures:
- The location of reinforcement
- The depth of cover
- The location of voids
- The location of cracks
- In situ density
- Moisture content variations
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It can be used to survey large areas rapidly for locating reinforcement, voids, sinkholes, pipelines, underground electrical and other cables and cracks.
It can be used for mapping webs in Pal-Kal ceilings lines and to determine their thickness, steel in beams and other nonstructural elements.
With increasing depth, low level signal from small targets are harder to detect due to signal attenuation.
The results can be shown in B Scan, Tomography or 3 Dimensional colored view.
Our company has two GPR units:
- 250 MHz for Soil and pavement mapping
- 1000 MHz for Concrete and structure mapping
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