Concrete structures such as slabs, walls, and columns may look solid and straightforward from the outside, but beneath the surface is often a dense network of steel reinforcement designed to provide strength and stability. Rebar provides tensile strength throughout a slab or wall, while post-tensioned (PT) cables—steel strands or wires threaded through ducts and tensioned after the concrete cures—can contain tremendous amounts of stored energy. Cutting into a PT cable can cause it to snap violently, releasing enough force to cause serious injuries or even fatalities on a job site. Even striking ordinary rebar can compromise structural integrity and lead to costly repairs, project delays, and other complications.
Concrete scanning—one of our core services here at Enhanced Scanning—is designed to help prevent these outcomes. It gives contractors, engineers, and property owners a clear picture of what lies beneath the concrete surface before a single core is drilled or saw cut is made.
How Concrete Scanning Works
The two primary technologies we use for concrete scanning here at Enhanced Scanning are ground-penetrating radar (GPR) and electromagnetic (EM) scanning. Each technology is suited to different applications and provides different types of information.
GPR is our most commonly used method for scanning concrete. A GPR unit is passed across the concrete surface, sending high-frequency radar pulses into the material. When those pulses encounter an object with different electrical properties than the surrounding concrete—such as steel rebar, a PT duct, a conduit, or a void—some of the energy is reflected back toward the antenna.
The scanning device records these reflections and translates them into data that allows a trained technician to map the location, depth, and orientation of embedded objects. GPR works well for both shallow and deeper scanning and can be used on slabs, walls, columns, and beams. It also does not require access to both sides of the concrete, making it useful in many different construction and renovation environments.
Electromagnetic (EM) scanning works differently. Rather than using radar pulses, it uses a magnetic field to detect metal, primarily rebar. EM scanning is generally simpler and more affordable than GPR, but it has a shallower effective depth range and cannot reliably distinguish between rebar, conduit, and PT cable. It confirms the presence of metal but does not provide the same level of information as GPR.
For this reason, EM scanning is often used for basic rebar mapping and concrete cover-depth verification, while GPR is generally preferred when PT cables, conduits, voids, or other complex embedded systems may be present in the concrete.
The Concrete Scanning Process
A typical concrete scanning job involves several steps. First, the technician identifies the area that needs to be scanned and establishes a grid pattern on the concrete surface for reference. The technician then passes the scanning device over the marked area in both horizontal and vertical directions to develop a more complete picture of what lies beneath the surface.
As embedded objects are detected, their locations can be marked directly on the concrete using paint, chalk, or other appropriate markings. The technician can also note the estimated depth and other relevant information about the detected objects.
For more complex projects, scan data can be documented and translated into detailed digital maps or reports. This information can give contractors and other project stakeholders a clearer understanding of where it is safe to drill, core, saw cut, or otherwise disturb the concrete.
When Concrete Scanning Is Needed
Concrete scanning is typically requested before coring, drilling, or cutting into a concrete slab, wall, column, beam, or other structure. It is particularly valuable on renovation projects, tenant improvements, parking structure work, and other construction projects where existing concrete may contain reinforcement or embedded utilities.
Concrete scanning is especially important in buildings and structures that use post-tensioned construction. High-rise buildings, parking garages, balconies, and other PT structures may contain cables that can pose significant hazards if they are accidentally struck during drilling, cutting, or coring.
Concrete scanning is a relatively small investment that can help prevent potentially catastrophic outcomes. By identifying rebar, PT cables, conduits, and other embedded elements before invasive work begins, concrete scanning helps protect workers, preserve structural integrity, and keep projects moving forward without costly surprises.
Contact Enhanced Scanning for Your Concrete Scanning Needs
If you have an upcoming project that will require you to disturb concrete, it is best to know in advance what is embedded in the concrete and where it is located. Taking the time to perform concrete scanning before beginning invasive work can provide valuable information and help your team work more safely and efficiently.
Contact Enhanced Scanning to schedule your concrete scan today. We complete concrete scanning projects throughout Southern California, as well as in Central Colorado.