When you cut, core, or drill through concrete, it's in your best interest to avoid rebar.
If you don't, it could cost you up to $12,000 per repair and as much as $30,000 to replace a single post tension cable
Severe work injuries and costs can occur, and the schedule delays while these repairs are taking place add up. And, of course, your company’s reputation will take a hit, which could affect your future earnings. The good news is, it doesn’t have to be this way because of accurate rebar scanner technology like ground penetrating radar (GPR), paired with a professional GPR concrete scanning and imaging Project Manager such as those found at GPRS.
What is Rebar?
Rebar, short for reinforcing bar, is the steel bar or mesh of steel wires used as a tension device in reinforced concrete. Its purpose is to improve structural integrity, strengthen and hold concrete in compression, provide additional support to handle tensile forces, as well as prevent cracks and fractures of the concrete under load. By doing this, it helps to ensure the durability and safety of buildings and infrastructure.
What is a Rebar Scanner?
A rebar scanner is a non-destructive tool such as ground penetrating radar (GPR) that uses radio signals to detect and image materials within concrete structures. When the radio wave encounters an object, it reflects back and produces a reading that displays these reflections as hyperbolas on the screen. This specialized tool is used by GPR concrete scanning Project Managers to locate structural reinforcements, such as rebar, within concrete slabs before any cutting, coring, or drilling takes place.
GPR technology is used to help prevent damage to structures and the equipment, as well as to ensure the safety of workers on job site's nationwide. GPRS Project Managers can accurately identify and mark the location of rebar reinforcements in the floor, ceiling, or wall slabs, using chalk, crayon marker, or paint as displayed in the image below.
How Deep Can a Rebar Locator Penetrate in Concrete?
When it comes to acting as a rebar locator, ground penetrating radar can typically penetrate up to 18-24 inches in concrete, depending on the conditions and the frequency of the radar. In fully cured concrete, GPR can achieve its maximum penetration depth since the material has a more uniform composition and lower moisture levels. However, in freshly poured concrete, the higher moisture content can significantly reduce the penetration depth of GPR. This is because the radar waves are more readily absorbed by the moisture, leading to less effective signal transmission and reduced clarity in the readings.
Can GPR Detect More Than Just Rebar Within Concrete?
Ground Penetrating Radar (GPR) technology has many capabilities beyond locating rebar and structural reinforcements. GPR can be used to detect a variety of other structural reinforcements as well before you core, cut, or drill. Other key elements that GPR can help identify include:
• Post Tension Cables: High-strength steel strands encased in plastic sheathes, pre-stressed to provide additional support to the concrete.
• Conduit: Tubes or ducts for enclosing electric or communication cables.
• Electrical Conduit: Specifically designed conduits for protecting and routing electrical wiring.
.• Heating Tubes: Systems embedded within the concrete to allow for underfloor heating.
• Voids: Cavities within a structure or underground. GPR cannot measure the void’s depth.
• Piping: GPR can detect pipes of all sizes, used for utilities and other purposes. Metal pipes are the easiest for GPR to detect. However, GPR can locate all variety of PVC and plastic pipes as well.
By accurately locating these components, GPR aids in damage prevention to structural reinforcements and helps you avoid safety hazards throughout any construction or renovation projects.
The GPRS Advantage
GPRS sets itself apart as the industry’s leading GPR concrete scanning contractor, with nationwide coverage and an industry-leading 99.8% accuracy rate on over 500,000 completed projects. The key benefits of choosing GPRS for GPR rebar and concrete scanning include:
• Green Box Guarantee: GPRS offers the unique Green Box Guarantee, which ensures that areas marked within a green box layout as shown in the image below prior to anchoring or coring will be free of obstructions. If any obstruction is encountered, GPRS commits to covering the cost of material damages, providing clients with peace of mind, reliability, and vendor integrity.
• Subsurface Investigative Methodology (SIM): The success of GPRS Project Managers in the field stems from the comprehensive training they receive upon joining our team. This training is based on the industry-leading Subsurface Investigation Methodology (SIM) for concrete scanning.
• Project Safety: By accurately locating rebar, conduit, and other potential obstructions within concrete, GPRS helps maintain a safe work environment, reducing strike risks, clashes, and structural damage.
• Budget and Schedule Compliance: GPRS' precise GPR concrete scanning services help avoid unforeseen change orders or repair costs, keeping projects on budget and on schedule.
"The biggest difference between GPRS and some of the other companies around here is that GPRS provides the Green Box Guarantee...I can't speak highly enough of GPRS...we are truly appreciative of that.” – Lee Pyfrom, Safety Director, MacDonald Miller
“GPRS ensured safe drilling areas in over 150 locations through very congested floor slabs. The accuracy of the information provided was remarkably sound.” – Mike Keith, Senior Project Superintendent at Turner Construction Company
“Overruns on cost can blow a project budget. When GPRS scans concrete or for utilities on our projects, it helps us limit unforeseen change orders or repair costs.” – Matt Morris, General Superintendent at Swinerton Construction
How To Find a Rebar Scanner Near You
For engineers and general contractors, employing GPRS for accurate GPR rebar and concrete scanning is not just a measure of safety, but a strategic decision that protects the integrity of your project’s infrastructure, the well-being of the workforce, and the financial health of the project. With the Green Box Guarantee, nationwide coverage, and unmatched accuracy, GPRS stands as a leader in ensuring that your projects remain on budget, on time, and safe, while also protecting your reputation.
Let us help you Intelligently Visualize The Built World® on any project, nationwide.
Frequently Asked Questions:
How much does it cost to repair post tension cable?
A single severed post-tension cable can cost upwards of $30,000 to repair or replace, and it can also lead to structural failure that endangers the lives of not only those completing the work but anyone in the immediate area.
How much does it cost to repair conduit?
The cost to repair a single conduit can vary widely depending on the extent of the damage, the type of conduit, labor costs, and location. On average however, you can expect to pay $12,000 for each repair. Avoid this by contacting the team at GPRS before you saw cut, core, or drill.
Is it possible to scan vertical surfaces or ceilings for rebar?
Yes, GPR rebar locators can scan for the location of rebar in concrete columns and walls. It can also scan the underside of a floor to mark out the reinforced steel and any embedded conduits.
