Cut, Core & Drill with Confidence

Concrete Scanning

Whats hidden in  your concrete | GPRS


Scanning concrete with GPR reveals rebar, post tension cables, electrical conduits, voids, and more. This is also an effective method of structural review including concrete slab measurement and rebar spacing.
Rebar Locating
Post Tension Cable Mapping
Structural Analysis
Concrete Thickness
Slab on Grade Applications
Shallow Utility Locating 

Conduit Mapping
Ground Penetrating Radar
 Proceq GP8800 GPR Scanner | GPRS
Ground Penetrating Radar
GPR scanners emit radio waves into concrete slabs and detect the interactions between these waves and any subsurface objects to create a readout of hyperbolas that vary in size and shape depending on the type of material detected. GPRS’ SIM-certified Project Managers interpret this data to tell you what was located and estimate its depth within the slab.
Concrete Thickness
GPRS Project Managers provide GPR scanning services to determine key slab information for structural engineers, including concrete cover and overlay thickness, concrete thickness, and even dowel placement. We aren’t limited by the size or scope of your site; we have the training and the equipment to fully evaluate your concrete structure.
Slab on Grade
Ground penetrating radar’s ability to visualize what’s inside and under concrete slab-on-grade is one of its biggest advantages over X-Ray scanning technology. Because GPR only needs access to one side of a concrete slab or structure to scan the material for anomalies such as embedded conduit, it can evaluate slab-on-grade.
Shallow Utility Locating
It’s not just the utilities within your concrete slab that you need to worry about – if it’s a slab-on-grade, you also need to avoid lines buried in the soil below. GPRS Project Managers utilize both ground penetrating radar and electromagnetic (EM) locating to provide you with a 99.8%+ accurate picture of the infrastructure within and below your concrete slab.
Conduit Mapping
We know you can’t risk severing an electrical conduit while coring or cutting through concrete. We mark our GPR findings directly on your slab so you know where all subsurface obstructions are buried and where you can safely cut or core.
Rebar Locating
Damaged rebar will cost you tens of thousands of dollars to repair, and that’s not counting any additional structural damage or injuries that occur when the support is damaged. GPRS Project Managers are specially trained to use GPR to locate and map the rebar within your slab or concrete structure.
Post Tension Cable Mapping
Our concrete scanning gpr service can locate post tension cables prior to core drilling. The results of our concrete scanning is marked on the surface of the slab but we can also build 2D CAD drawings and a 3D BIM model of the interior of your slab that shows post tension cable layout.
Strutctural Analysis
For specific structural analysis testing, GPRS uses GPR and electromagnetic (EM) locating in tandem with Ultrasonic Pulse Velocity (UPV) testing and imaging, tomography, drone photogrammetry, and even 3D laser scanning services to completely assess concrete structures.


Data Control = Damage Control, which means you save time, money, and keep your people safe.
Project Cycle Solutions Graphic | GPRS
Planning & Design
GPRS provides existing condition documentation and accurate utility maps, visualizing your entire facility above and below ground before plans and developments are finalized. All our field-verified markings and reports are delivered via SiteMap®, which gives you 24/7 access and secures your data in a single source of truth.

We Intelligently Visualize The Built World® through utility locating, concrete scanning, 3D laser scanning, video pipe inspection (VPI) reporting, and leak detection to provide you with accurate as-builts of your entire infrastructure. Our in-house Mapping & Modeling Team can integrate your existing as-builts and even proposed changes to assure accurate measurements and locations of existing assets, to save you time and money.
Prior to cutting or coring concrete during the construction or renovation of your site or facility, it is critical to accurately locate and map all infrastructure embedded within and buried below the slab.

GPRS provides precision concrete scanning & imaging services to mitigate the risk of subsurface damage when cutting or coring concrete.
In construction, changes happen. GPRS helps you focus your plans with 2-4mm accurate CAD drawings & 3D BIM models that can integrate all your infrastructure as-builts and provide you with accurate floor plans via FLRPLN, so you can target your workflow safely and efficiently.


Ground Penetrating Radar (GPR)
GPRS employs the Proceq GP8800 Ground Penetrating Radar Scanner for precision concrete scanning & imaging. Its 400-6000 MHz modulated frequency range means we can locate a wide range of subsurface objects with one pass, and its wireless functionality allows us to scan hard-to-reach locations or uneven surfaces.
EM Locating
GPRS uses the Vivax vLoc3-Pro Electromagnetic (EM) Locator to passively detect the signals from live AC power or radio signals travelling along conductive utilities. We also use it in conjunction with a transmitter to connect directly to accessible metallic pipes, risers, or tracer wires.
3D Photogrammetry
GPRS’ in-house Mapping & Modeling Team can export the GPR concrete scans completed by our SIM-certified Project Managers to create accurate existing condition as-builts to give you the information you need in a format you can easily work with and share to keep your project on time, on budget, and safe.



GPRS commits to:

Provide elite project managers with a proven 99.8% accuracy rate
Utilize multiple complementary technologies to locate and identify subsurface utilities and/or embedded features
Follow industry-leading SIM protocols to get the most accurate results, everywhere, everytime


Hire only SIM-certified contractors for locating and concrete scanning
Provide an explicit dig policy for your crews that specifies the use of SIM protocols
Put data accuracy and safety at the top of your list


An industry-leading, proprietary program that provides contractors the necessary assurance of safety when drilling, cutting, or coring through an elevated concrete deck. When GPRS places a Green Box within a layout before cutting or coring concrete, we guarantee it will be  free of obstruction.
Magnifying glass with check | GPRS
Electrical conduit strikes present a high risk of electric shock to the equipment operator and nearby workers. Strikes can also cause nearby operations and work to be shut down. Cutting, coring, or drilling through a post-tension cable can cause structural damage or injury. Severed post-tension cables can lead to compromised structural integrity, creating severe safety concerns for everyone involved.
GPRS Project Managers can accurately clear dozens of cutting/coring areas per day. Cutting, coring, and drilling through concrete clear of obstruction can significantly speed up the demolition process. When contractors can keep their schedule from experiencing delays due to line strikes and damaged reinforcement, change orders and budget overruns are decreased.
It can cost thousands of dollars to repair damaged wire and conduit due to an electrical strike. Post-tension cable repairs and restressing can cost several thousand dollars per tendon. Cutting through a post-tension cable, critical rebar, electrical conduit, or other obstruction can cause a job site to be shut down, increasing costs.
Clear Communication
Green Box Guarantee information is presented directly on the surface of the coring location. GPRS performs post-job walkthroughs to explain all Green Box Guarantee locations and parameters. GPRS leads the industry in project accuracy. Year after year, our performance is 
 well over 99% accurate.
Construction worker icon | GPRS
Capturing accurate and up-to-date existing conditions for the infrastructure embedded within and buried below your concrete can greatly reduce or eliminate subsurface damage when you cut or core that concrete. You’ll save money and keep everyone at your facility safe.

GPRS can provide individual concrete scans when you need to cut or core, or a full site scan for future O&M purposes. And all this field-verified data is at your fingertips 24/7 via SiteMap®.
Engineer icon | GPRS
Protect your team, your budget, your schedule, and your reputation from the dangers of subsurface damage. GPRS Concrete Scanning Services give you the peace of mind that comes from knowing you can cut or core with confidence.

Our SIM-certified Project Managers will mark their findings directly on the slab to make it crystal clear where it’s safe to cut or core – and where penetrating the slab could have disastrous consequences. And with that data captured with 3D laser scanning and securely stored in SiteMap®, you’ll be able to communicate this information with your entire team when they need it, from wherever you are.

///INDUSTRIES We serve


SiteMap® is a project & facility management application that provides accurate existing condition documentation to protect your assets & people.
SiteMap - GIS Infrastructure Software Application on Mobile and Desktop | GPRS

SiteMap® Project

All GPRS customers receive a SiteMap® Project tier subscription with every job we complete. SiteMap® Project is designed to streamline the process of information upload in infrastructure development projects, providing you a platform where all your relevant infrastructure data – including precision concrete imaging – can be stored, accessed, and managed efficiently.


Work completion change orderwalk through 3D | GPRS
Virtual Change Order Completion Verification
Verify completed work, approve change orders, take rough measurements to help avoid reworks, and keep your team’s workflow moving – whether your team is on-site or remote. This virtual tour option can assist you with the communication process for coring when approval is needed from the site structural engineer.
Remodeling walk through 3D map | GPRS
Virtual Site Walks
Give stakeholders, contractors, designers, and trades a complete virtual tour of your site or facility that can capture survey marks, excavation, utilities, paving, concrete work, and more prior to your build. After the work is complete, GPRS can create an updated WalkThru 3D tour to allow your stakeholders, potential tenants or buyers, and others to walk through the finished project.

///Case Study

Accurate PT Cable Layout 
Critical to Construction:
Mapping the support grid in your concrete slab facilitates design and minimizes 
the risk of injuries and delays.
GPRS partnered with Turner Construction to locate and mark the full post tension cable system layout for floors 12-23 of a 49-story building, with approximately 12,500 sq. ft. of concrete on each floor. After concrete scanning was completed with ground penetrating radar technology, GPRS 3D laser scanned each floor to produce 2D CAD drawings and a 3D BIM model for virtual design and construction. The architect received a permanent record of the post tension cable layout to complete fit and finish design plans for the 12 floors of the building.
Screen shot of grps services mocked up on a desktop monitor | GPRS
The Bottom Line:
GPRS' detailed 2D CAD plans and 3D BIM model allowed for precise planning, and safe MEP and HVAC installations.
Pre-Pour example | GPRS
Concrete locate field markings depth and elevation | GPRS
Concrete Locate Field Markings Depth And Elevation
3D BIM Model of
PT Cable Layout
Chat box with question mark | GPRS
Accurately mapping the interior concrete slabs of 12 floors (12,000 s.f. each) of PT concrete in a 49-story high-rise.
Magnifying glass with check | GPRS
The AEC team required precise interior PT slab mapping for design, planning, and construction of their mixed-use building. Every PT cable bears up to 30,000 Ibs. of load and costs $20,000-$30,000 to replace.
Notebook with checks | GPRS
GPR was employed to accurately scan the interior of each slab. The surface markings were then 3D laser scanned so that the Mapping & Modeling Team could build accurate 20 CAD drawings, and a 3D BIM model of the interior of each slab, including individual and bundled cable drape.

///Put Your Site on the map

Concrete Markings
The main goal of concrete scanning and imaging is to protect the structural integrity of the concrete, ensuring the safety of everyone involved in the project. Our job is to detect and mark sections of reinforcing steel and other subsurface anomalies in the concrete to help you and your team avoid injury as you cut, drill, and otherwise penetrate the surface.
3d cad
To help you fully visualize your job site, GPRS offers 3D mapping and modeling to document interior findings. These realistic 3D CAD files document the vertical and horizontal elevations, providing a more accurate, easier-to-read visual than your standard 2D model.
2D Cad
Assess existing structural conditions, walk your team or stakeholders through your project or entire facility, take rough measurements for planning, design, or maintenance, and capture floor plans and construction progress with 3D photogrammetry or laser scanning.
Concrete scanning data collected on your site by our SIM-certified Project Managers is instantly uploaded into SiteMap®, our infrastructure mapping solution where you can securely access and share this data with your team 24/7 from any computer, laptop, or smartphone.

///Case Study

Concrete Scanning for: Denver Center for the Performing Arts Wall Removal
Turner Construction was required to alter the layout and access points of the structure extensively. Hundreds of concrete core holes were needed to install new electrical, plumbing, HVAC, and fire systems.
The Denver Center for the Performing Arts hired Turner Construction to complete concrete removal for a large tenant improvement project, requiring extensive concrete infrastructure changes.
The Bottom Line:
GPRS’ 99.8%+ accurate concrete scanning services allowed for concrete coring to be completed without incident, protecting the client’s team, budget, schedule, and reputation.
Chat box with question mark | GPRS
Scan and clear hundreds of concrete coring locations in the Denver Center for the Performing Arts.
Magnifying glass with check | GPRS
Turner Construction was hired for extensive concrete removal on a tenant improvement project. It was critical to avoid striking existing reinforcements in areas not being removed due to the building's age and the extent of the work needed.
Notebook with checks | GPRS
GPRS scanned proposed coring locations to mitigate subsurface damage risk. Our SIM-certified Project Managers used ground penetrating radar to accurately mark findings on the slab surface, aiding core drillers' understanding.


Can ground penetrating radar scan concrete slab-on-grade?

Yes, it can. Unlike with X-ray, where both sides of a concrete slab must be accessible to obtain a picture of the subsurface structure, GPR only requires access to one side of a slab to obtain a comprehensive view of what’s inside. This makes it an ideal technology for evaluating concrete slab-on-grade.

Can ground penetrating radar identify the difference between rebar, post tension cables, electrical conduits, and other embedded materials?

GPR on its own does not tell you what type of object has been located, which is why it is inadvisable to attempt to complete this type of work yourself. Fortunately, GPRS Project Managers are uniquely equipped to interpret the data collected by a GPR scanner to identify the type of embedded material present. Every GPRS Project Manager is required to complete the Subsurface Investigation Methodology (SIM) training program, which involves 320 hours of field training and 80 hours of classroom training. Through this regimen, our Project Managers tackle real-world scenarios in a safe and structured environment where they can learn to tackle these challenges with the highest level of accuracy and professionalism.

How accurate is ground penetrating radar with marking anomalies in concrete?

When operated by our highly trained Project Managers, GPR’s typical accuracy is +/- ¼” to the center of the object in concrete we locate: conduit, post tension cables, and rebar. We can also pinpoint the depth of every object we locate in concrete with an accuracy of +/- 10-15%. Because our accuracy while scanning with GPR is so high, we can offer you our professional opinion to help you know where you are able to drill without the risk of hitting any objects marked on the slab. For safety concerns, we always tell our contractors to move one-to-two inches from any marked line as they prepare to cut or drill to be sure they safely miss any embedded objects. We are so confident in the accuracy of our Project Managers that we introduced the Green Box Guarantee, which states that when we place a Green Box within a layout prior to you anchoring or coring concrete, we guarantee that area will be free of obstructions. If we’re wrong, we will pay the material cost of the damage.

Are there any health risks associated with ground penetrating radar?

No. This concern usually comes from someone familiar with X-ray technology, which carries the health risk of radiation-exposure. This is one of many reasons why concrete scanning and imaging with GPR is considered a safer, more efficient, and ultimately more successful alternative to X-ray. The typical power output of a GPR antenna is less than what is produced by the cell phone in your pocket. As a result, there are no health concerns with our Project Managers, construction workers, or tenants in the building where scanning is taking place. Additionally, GPR scanning is a quiet process, so noise issues are also not a concern.

How long does it take to scan an area for core drilling?

Ground penetrating radar is an extremely efficient and rapid technology. Large areas can be easily and quickly scanned with the state-of-the-art GPR units utilized by GPRS Project Managers. Our standard layout for a typical core drilling location is 2’x2’. It usually takes about 10 minutes to scan and mark an area this size.