With radio surveys one can easily able to detect the non-metallic buried services like gas pipes, plastic water pipes, drainage pipes, etc. In order to overcome this hazardous situation, the use of Ground Penetrating Radar with Radio detection is combined. GPR survey can detect metallic and non-metallic pipes easily. At the same time it can also provide the depth and location of the buried services. But it will not able to identify the pipes. Apart from this, radar survey can also be used to locate the extension of tree roots.
This survey can also be used to locate different voids and RSJs in walls and platforms. The thickness of asphalt and concrete slabs can also be determined with underground cable detector. Generally, GPR does not trace the services, but simply indicates the trenches, presence of voids, cables and pipes buried underground and disturbed ground. This radar survey system works by emitting an energy pulse under the surface. Echoes come back after hitting the interfaces present between different materials under the earth.
There are numerous advantages of using Ground Penetrating Radar. Radar surveying can not only detect non-metallic and metallic services like gas pipes and polyethylene water, but also utilities like fiber-optic cables that are not impossible to trace using some other methods. With this radar survey alone, it cannot be guaranteed to identify and find all the services buried underground, but it can provide the user with perfect results when used along with Radio detection. All radar surveying scans are usually recorded at the site and analyzed and post-processed in the office before inclusion on OS mapping and digital site drawings. There are some guidelines and regulation for using this survey method. A Policy Statement is there which imply outlines the Survey Strategies of GPR for the location of the underground utilities. At the same time it also outlines the negative and positive effects of ‘off-site’ and ‘on-site’ GPR scan record interpretation.
With Radio detection, surveys can be carried out easily on different services that can be identified from the inspections around an area. This can also be used in carrying out the scanning service at the survey area, looking for signals that exist in cables buried underground. Radar survey is carried out by emitting a sound method. The transmitter is passed over the surface of the ground. It sends radio energy of low power and reflections from the boundaries of the materials as well as embedded features like voids, metal and buried cables, which are picked by the receiver. The outcomes are viewed on the monitor and also recorded for later analysis onto the disk. Radar is highly effective on uneven surfaces as well as through multi-layered media.
The material above the buried services and surrounding it can directly affect whether the particular service can be easily resolved by the GPR method. Buried metallic items, reinforced concrete, the presence of clay and moisture as well as the changed in the construction material may lead to poor resolution of data. GPR method can provide depth results with horizontal accuracy of +/- 150mm and typical accuracy of +/- 10%. Radio detection can penetrate far deeper than the GPR system. It’s accuracy is +/- 10%. To know more about how GPR helps in pipe inspection camera and services detection you can browse online.