GPR is a highly useful tool for archaeologists, geotechnical engineers, and utility locators because it provides valuable information before digging or disturbing ground. It works by transmitting high-frequency electromagnetic waves that reflect off objects in the ground or in man-made structures. These reflections are measured by a receiver antenna. This allows for the visualization of subsurface anomalies such as rebar in concrete and utility lines underground. The technology is non-invasive and requires no ground disturbance. It is effective in most soil conditions and is a quick method to survey large areas. Check this out:gpr-survey.uk

In general, a GPR system uses a single unit that functions as both transmitter and receiver. The system transmits pulsed radio signals that are in the microwave range and are reflected off of objects within the ground. The signals are displayed on a screen as hyperbolas that an experienced GPR technician interprets. This process helps locate and identify objects such as pipes, wires, tanks, reinforcing steel in concrete, graves, boulders, tree roots, and other voids.

The Role of Ground Penetrating Radar in Concrete Inspection

Unlike electromagnetic (EM) methods that detect objects by measuring the velocity of subsurface layers, GPR measures the time delay between the transmitted signal and the first detection of a return signal. The depth to which a target can be determined depends on the type of material and the frequency of the GPR pulses used. For example, dry sand and granite are capable of reaching over 100 feet (30 meters) while moist clays or shale may attenuate or absorb the signals.