When it comes to finding out what’s inside a concrete slab, non-destructive options are generally the first choice. The two main options are the use of x-rays or ground penetrating radar (GPR) to “see into” the concrete slab or structure. Both provide a closer look at what’s inside, including rebar, conduit, post-tension cables, and more.
GPR usage is often the first choice when scanning concrete, and for good reason. It’s an extremely effective method of determining what lies inside of concrete structures. Ground penetrating radar is non-destructive and emits no harmful radiation. It can be used to quickly scan large areas with no prior set-up necessary. Access is only needed for one side of a slab or structure, and the radar can generally penetrate depths of 18-24”. GPR use is comparatively lower in cost than other methods such as x-ray imaging.
While concrete x-ray is an older form of technology, it’s extremely effective at providing clear imaging. X-ray is generally considered more precise than GPR scanning since there is less room for interpretation of the results. The x-ray is able to show more detail about the condition of embedded objects such as rebar- it’s even possible to show areas of corrosion or other defects.
GPR scanning is the #1 choice for concrete scanning and imaging due to its speed, efficiency, accuracy and cost effectiveness. X-ray imaging requires access to both sides of the concrete making it difficult to use in many instances. The use of x-ray imaging also emits harmful radiation to technicians and those in the area- special precautions must be taken to ensure site safety. For this reason x-ray work is generally performed after hours, adding to the overall cost. The x-ray process is slower than GPR scanning, and images must be developed off-site as opposed to the immediate results which can be provided when using GPR. X-ray images may be inadvertently flipped by the technician interpreting the results, leading to an incorrect analysis.
Ground penetrating radar is considered the go-to technology for concrete scanning, though accurate interpretation of results is dependent upon properly trained technicians. Ground penetrating radar has fewer limitations that x-ray imaging and the quality of the results is generally more than sufficient for most applications. Use of x-ray may be advisable when GPR scanning is unable to pick up necessary detail, or in an instance where tight tolerances call for absolute precision.
Note: GPRS does not provide geophysical, geological, land surveying or engineering services. If you need such services, please contact an appropriate professional. What does an underground utility locator do?