Ground penetrating radar is a very useful device for locating buried systems, like underground utilities. It can help to create a map of things that lie below concrete slabs and is used to assist construction, maintenance and repair.
Earlier systems for locating underground piping used metal detectors, but this required the pipes to be made of metal. With the use of pipes made of PVC or HDPE gaining a lot of prominence, metal detectors were not found to be useful, and hence the greater use being made nowadays of ground penetrating radar. This radar can locate objects made of any material, and this gives a very accurate picture of things that lie below the ground or below concrete slabs. This enables all the obstacles to any activity to be known in advance, and assists in planning of operations, so that time is rarely wasted, and the digging to reach the location limited to very precise locations. This can also be a great money saver, as this radar can even help to spot defects in pipes, leading to it being able to define the area affected and which needs attention.
The equipment that helps ground penetrating radar transmits sound waves of very high frequency, which can penetrate ground to several feet below and concrete of some thicknesses. These sound waves then bounce back to the receiver that is part of this equipment. This gives information of the depth to which the sound waves have reached, and the density of the materials that are hidden from view. The equipment is calibrated so that is can create a detailed map of the utilities which are hidden. This calibration is based on known times to penetrate various materials and this gives the technician the information that is required. A number of passes are made over each area to confirm and reconfirm the results, so that the right conclusions can be drawn.
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There is virtually no limit to the utility of this form of radar equipment, and besides detecting pipelines and other utilities running below ground or concrete slabs, it has been of great help to archaeologists who can identify the existence of objects below ground, and save themselves the trouble of excavating in areas that do not contain any artefacts. Geologists use it to identify the various types of soils below ground. Engineers use it to penetrate concrete slab to judge the rebar within the concrete and find it very useful as a form of non destructive testing, when the structural capability of buildings is in doubt.
Ground penetrating radar equipment is expensive and sophisticated and requires the technicians using it to be very well trained. The usage on most projects or sites is very limited, and this has led to companies who own such equipment to hire it out to casual users, or even undertake particular assignments which are within the capability of their equipment. Ensure that any company that you hire for this work has the right technology, trained staff and the experience in carrying out the type of work you want them to do.