30.10.2014 | 20:20
What You Should Know About Sub-surface Surveying With Ground Penetrating Radar
Ground Penetrating Radar (GPR) is something that companies use in order to locate buried objects and detect their precise location at the fastest time possible. There are a lot of uses for ground penetrating radar, however, it’s mostly used for cables, and pipes. While the technology for ground penetrating radar is complicated, you can think of it in very simple terms it’s a GPS for the underground.
GPR can be utilized on different surfaces, including the ground, stone, ice, fresh water, sidewalks, and construction sites. It can find lost items, track changes in the substance of the subsurface, and detect voids and cracks. GPR uses high frequency (normally polarized) radio waves that blast to the bottom. When the waves hit the border of a buried object or an anomalous surface, the receiving antenna records the variations.
While the technology for ground penetrating radar is accurate, it’s not without its limits. The electric conductivity of the earth, the transmitted center frequency as well as the radiated power limits the depth range. As conductivity rises, the penetration depth falls. That is due to the fact that the electromagnetic energy is rapidly turned into heat, causing a decrease in signal strength.
Higher frequencies don’t penetrate as far as frequencies that are lower but broadcast better reception. The maximum depth penetration for ice is several meters. Also, great penetration is possible in dry sandy soils or substantial dry substances like concrete, limestone, and granite where the depth could be up to 15 meters or 49 feet. In damp soils, clay material, and soils with high electric conductivity, penetration is only possible for up to several centimeters.
ATLG Brisbane ground-penetrating radar antennas are usually used for the most powerful signal strength; yet, GPR atmosphere-launched antennas are also used.
Aside from locating objects, GPR is also used in the Earth sciences. It can be used to analyze groundwater, soils, bedrock, and ice.
It also has engineering uses, including nondestructive testing of pavements and structures, finding buried utility lines and structures, and analyzing bedrock and soils. It can also be used for finding underground graves. The military uses the technology in order to detect unexploded mines and tunnels.
In mining, borehole radars using GPR are employed to plan the arrangements from a borehole in underground mining. Modern directional borehole radar systems can generate three-dimensional pictures from measurements within a borehole.
GPR can also create 3D subterranean pictures of power conduits, sewage, and water mains. This technology is usually called PAT, or Pipe Avoiding Tool.
In archaeology, is used to discover and map subsurface archaeological artifacts, and patterning. GPR can reveal a crypt the in a historical graveyard.
As we said before, GPR is not without its limits. It’s highly limited in capability when used in clay soils and similar surfaces. Another disadvantage of GPR is that it consumes a lot of energy. But these disadvantages do not discount the fact that GPR is highly useful in other situation.