Performing work on existing concrete is often a necessary part of construction. Coring, drilling and cutting are just a few of the techniques which are used on concrete slabs and walls. This concrete can contain rebar, conduit, post tension cables and other materials, with the potential to cause major damage if hit.
The use of concrete scanning is a smart way to lessen or eliminate the risk that comes with performing invasive work on existing concrete. Scanning is a reliable way to find out what is hidden within the concrete’s surface, in order to avoid hitting it. Cutting into a post tension slab, hitting a structural component, electrical conduit or a water main can cause immediate and costly damage. Even worse, it can cause serious injury to anyone on site.
Concrete x-ray is the most traditional method of scanning concrete. While the x-ray process is still used, it has become less popular since it’s time consuming and requires that both sides of the concrete are accessible. Concrete x-ray only detects certain materials within the concrete, not to mention the equipment is cumbersome and produces harmful radiation.
Today, concrete scanning technology has evolved beyond the concrete x-ray. A concrete scanner called ground penetrating radar (GPR) is used to send radar waves of a certain frequency into the concrete being scanned. The waves are bounced back if they hit an abnormality such as rebar, conduit, cables, voids, etc. This provides a clear overview of the concrete’s subsurface. While the radar does not automatically distinguish between different materials, GPRS’s highly skilled technicians are trained to recognize the patterns produced by each of these anomalies. This information is used to carefully mark out the concrete, enabling the contractor to visualize exactly where work can safely be performed.
Without the use of concrete scans there is no way to know for sure if something will be hit. Concrete is designed with a certain amount of rebar in order to provide necessary strength and safety. Damage to rebar creates immediate stress on the concrete, causing issues which must be repaired in order to restore the structure’s stability.
Post-tension cables are another structural component which can cause massive destruction if compromised. Post-tensioning occurs when structural cables are placed through slabs and a high amount of pressure is applied to tighten them, resulting in increased strength to the slab. Damage to post-tension cables can cause immediate injury to workers, as well as irreparable structural damage to the post-tension slab.
In addition to these common structural components concrete often contains electrical conduits (both plastic and metal), water lines and radiant heating lines. The dangers of striking an electrical line include worker electrocution and power outages. Ground penetrating radar can be used to assess leaks or damage to buried water lines which would otherwise be hidden to the eye. Damage to electrical, water and heating are repairs which must be made quickly and correctly in order for work to continue.
In addition to detecting the presence of materials within the concrete, GPR can also be used to detect the absence of material. Voids are empty spaces often present in concrete due to improper pouring technique or previous damage. Determining the location of voids is useful in assessing areas of weakness or areas which may need further repair work.
GPRS uses ground penetrating radar to quickly and effectively find post-tension cables, rebar, conduit, voids, and anything else present within the concrete. Our Project Managers are rigorously trained to distinguish between different readings; and can determine where destructive work should be avoided.
Taking the time to perform a concrete scan eliminates the possibility of damaging components within the concrete, saving you time and money and most importantly, keeping your team safe. GPRS has locations in major hubs throughout the United States, making it easy for us to access all of your projects. A few hours spent scanning concrete can prevent countless hours of frustration when performing invasive concrete work.
Note: GPRS does not provide geophysical, geological, land surveying or engineering services. If you need such services, please contact an appropriate professional.