How GPR Contractors Help with Concrete Construction

by Tendon, on Nov 17, 2022 7:00:00 AM

Ground penetrating radar (GPR) is a misnomer. That’s because GPR has essential and nearly limitless applications in concrete construction, in which this technology is used to scan concrete — not the ground.

So, how exactly do GPR contractors use their concrete scanning expertise to help with concrete construction projects? That’s exactly what we explore in this post. For more information, see below. And to get help with your concrete construction projects, reach out to the GPR experts at Tendon Systems.

How GPR Works

Before we dig too deep into how GPR contractors actually help with concrete construction, we should understand how GPR works. Like any type of radar, GPR uses radio waves to produce an image. The image GPR produces shows what is beneath or within a surface, such as concrete. 

The radio waves emitted from the GPR unit penetrate the surface and scatter or reflect off of structures within the surface. The scattering or reflection will disrupt the pattern of the waves, which a receiving antenna on the GPR unit can detect. GPR contractors can analyze the image that returns to the GPR unit to determine what object beneath or within the surface caused the disruption. Typically, GPR can penetrate concrete components at depths of up to two feet.

3 Ways GPR Contractors Help with Concrete Construction Projects

Whether you are discussing new construction, selective demolition or repair or restoration of concrete, it’s difficult to imagine a concrete construction project that would not benefit from the services of a GPR contractor. With that said, there are three primary ways in which GPR can benefit a concrete construction platform.

1. Finding Post-Tension Cables, Rebar and Electrical Conduits

One of the most important functions of GPR in concrete construction is locating important elements within existing concrete foundations, walls and ceilings. The following are some examples of items a GPR contractor can locate inside an existing concrete structure:

This application of GPR is particularly useful when evaluating an existing concrete foundation for new construction and conducting selective demolition of an existing concrete structure in order to rebuild or add to it. 

For example, in selective demolition, a GPR concrete scan can tell you which parts of the walls may contain metal elements like cables and rebar that could pose risks when cutting into the concrete, in addition to helping you preserve sections that contain critical wiring or plumbing.

Also, the ability to avoid accidentally cutting into important post-tension cables can save an enormous amount of money for a concrete construction project. GPR contractors should be confident enough in their abilities and analyses to guarantee that no cables will be damaged during concrete scanning or cutting. And they should be on the hook for repair or replacement costs in the event that a cable is damaged.

2. Evaluating Concrete’s Structural Integrity

Because GPR provides a detailed image of everything that is inside of an existing concrete structure, experienced GPR professionals can use this method to evaluate the structural integrity of existing concrete. Understanding the structural status of an existing foundation or wall can tell builders whether repairs must be done before any new construction can begin.

A GPR scan can show not only the number of post tension cables inside a given portion of concrete, but also their spacing. This information can also add to the contractor’s understanding of the current strength of the concrete.

Existing concrete that is somewhat older may present structural problems that have less to do with the existence and number of post tension cables and more to do with the condition of the cables. The cables are embedded deep in the concrete, so the condition of these cables is only guesswork — unless you involve an experienced GPR contractor. 

An experienced concrete scanning professional can analyze the speed with which the radio waves that reflect off of rebar and other metal cables to understand whether the object is corroded. That’s because a corroded cable will “bounce” the signal back more slowly than a cable that is still new and strong.

3. Providing Accurate Cost Estimates

With the ability to detect the existence and quality of post tension cables and other elements inside existing concrete comes the ability to develop a more accurate cost estimate of the project. A GPR contractor can help you understand whether concrete repair will be necessary before construction can begin, as well as whether selective demolition will be a simple or complex process.

Add to that the fact that GPR scanning can help builders avoid accidentally damaging existing supportive cables. That means fewer unexpected costs will be able to sink the project’s budget.

Work with the GPR Experts at Tendon Systems

GPR contractors provide an essential service to almost any kind of concrete construction project. They help save time and money, prevent accidents and provide estimates for concrete construction projects of all kinds.

At Tendon Systems, we are GPR experts. To learn more about our concrete scanning and coring services, reach out to us. Give us a call at 678-835-1100 or contact us online to discuss your project with our team.