GPR is used by criminologists, historians and archaeologists to search for burial sites. GPR users implement their systems to locate and document targets under or behind surfaces.
Whether it’s scanning concrete walls, probing the ground, or whatever, GPR can provide a holistic imaging solution that traditional technologies can’t provide. GPR applications in the field include the location of buried utilities, the assessment of structures, and the search for buried artifacts, among others.
GPR or ground penetrating radar is used in several areas to observe artificial and natural elements. GPR can detect underground tanks, metal and non-metallic pipes, electrical lines, detection of underground conduit such as water pipes, rebar and post-tension cables inside concrete.
The GPR waves are equal to those of a cellular phone or Wi-Fi network, while X-rays require 50 feet of clearance before being used for safety reasons. In general, GPR is the most cost-effective option and the fastest method to test concrete.
The principle of using radio waves to determine the internal structures of the soil has long been known. Early work in this area included the use of radio echo sounders to determine the thickness of ice sheets in the Antarctic and Arctic and to measure the thickness of glaciers, which was undoubtedly the greatest success. GPR detection in non-aglacial locations was initiated in the early 1970s.Early achievements focused on work on permafrost soils.
GPR is a device that uses waves of energy in the microwave range. The transmission in the control unit is responsible for sending electromagnetic energy into the earth or material to be examined. When the sent waves reach an underground object, the latter returns or refracts the waves. The detector then captures the feedback signals emitted by the object and records their possible variations.
Thanks to the software installed in the GPR, these signals are then converted into images of the various elements underground. The system is therefore used to locate utilities and infrastructure that could be buried in the basement to avoid damaging them during renovation or construction work.
Microwave emissions sent by hidden objects are recorded and digitized by the control unit software as waveforms. Ripple patterns are used above the waveforms to present reflections deeper underground.
The size or amplitude of the waveforms is color-coded when the coils are moved over the study area. Positive waveforms have lighter colors, while negative waveforms have lighter colors.
These colour codes represent the origin of the analyses. It is easy to translate them into 3D images to better understand the exact nature of the elements that were scanned. This information can also be converted into drawings using adapted CAD technology. Images and drawings make it easy to locate underground utilities to avoid them safely during excavation or construction.
GPR uses are numerous and varied. Here is a quick overview of some of the most common applications:
Engineering and Construction: GPR can detect objects in concrete, detect voids and cracks and determine the thickness and depth of concrete slabs.
Military: Detection of underground tunnels and unexploded objects.
Environment: This tool can also detect oil tanks, map the nature of the leakage of the contaminant flow, assess the limits of a landfill.
GPR detection has completely changed the rules regarding concrete sweeping and a multitude of construction projects where it is essential not to damage underground utilities. Below are some of the benefits of GPR underground detection:
As mentioned above, GPR underground detection is a good method for locating utilities. It is easy to use GPR, it does not require a lot of personnel or equipment. For more information on GPR detection, please contact us now.