Why Contractors Use Ground Radar Equipment to Locate Utility Lines
Ground radar equipment uses electromagnetic waves to detect objects and structures in the subsurface. It can determine the density of soil layers and identify underground features. It can also detect buried metal objects, such as pipes and rebar in concrete structures. However, the system must be able to distinguish these metallic objects from other materials, and the signals can be disrupted by metal surfaces. This limits its usefulness to nonmetallic, nonconductive objects or boundaries in the ground.
The underlying technology in GPR is simple: It sends radio frequency waves into the ground and measures how long it takes for those signals to reflect back to the antenna. The two-way travel time is used to calculate the depth of a target object or material. The signal penetration of a GPR system is influenced by its transmitter frequency, with higher frequencies providing more details at the surface but less depth. The latest systems allow users to “jump” across multiple transmitter frequencies for the best performance in a given application.
Essential Equipment for Ground Radar Surveys
While a GPR system cannot be used alone to locate underground utility lines, it can complement other methods like electromagnetic locating and visual inspections. When a contractor uses GPR and other methods in conjunction, the results are more consistent and error-free than using one method without the other. In addition, GPR is less invasive than digging and can reveal utility lines that may be hidden from other detection technologies. As a result, contractors that use this geophysical tool can save both time and money.