Ground penetrating radar (GPR) is a geophysical survey Technique and the main component of a PAS 128:2014 for utility detection and mapping survey.
Ground Penetrating Radar operates by transmitting high-frequency radio waves pulses down into the ground through an antenna. Ground Penetrating Radar is distinctly able at not only mapping buried structures but also relatively measuring their depth, and supplying an all-important thorough detail.
The antenna is moved over the surface to be inspected. The transmitter redirects a diverging beam of energy which is reflected in various underground objects or different contacts between different earth materials.
The radargram measured on the vertical scale is in units of the two-way travel time, that’s the time taken by the EM wave to travel down to a reflector and back to the surface. The travel time then is transformed into depth by relating it to on-site measurements or assumptions about the velocity of radar waves in the subsurface material under investigation. Radar wave speeds vary between 60–175 mm/ns for most geological materials.
GPR waves can travel almost 30 meters deep in low conductivity material, as in case of dry sand or granite. Clays, shale, and other high conductivity materials may lessen or absorb GPR signals, leading to the reduction in depth of penetration to 1 meter or less. The GPR antenna can determine the depth of penetration as well.
The selection of antennae is based according to the depth of interest and the size of the target. Penetration depth varies in contrast to the frequency. The higher the central frequency of antenna, the smaller will be the object size to be resolved. Higher antenna frequencies give higher resolution, but less penetration, and vice versa. The lateral and vertical resolution of the results varies from 0.01 to 1.0 meters, as per the choice of antenna frequency. Use of antennae having lower frequency in geological mapping is done to obtain the maximum penetration depth while higher frequencies are used in non-destructive testing for high-resolution imaging. Having a range of frequencies available (usually 50MHz–2.5GHz) makes GPR most suitable for identifying objects of different sizes at different depths and under different ground conditions. We are one of best Ground Penetrating Radar Survey Services, Best Underground Utilities Survey Services and GPR Survey Service in India.
Ground Penetrating Radar Survey Applications
Utility Detection and Mapping
Detect and figure out buried structures including utilities, foundations, reinforcing bars, cavities, tombs, archaeological artifacts, and animal burrows. Subsurface piping leak detection and leak impact assessment (presence of washouts or voids). If you are looking for Ground Penetrating Radar Survey Services, Best Underground Utilities Survey Services and GPR Survey Service in India then you are at the right place.