Concrete Scanning - GPR vs. Concrete X-Rays by ScanMan

These days the importance of assessing concrete structures cannot be overemphasized. Today's construction industry focuses on locating imbedded objects such as tendons and other internal structures prior to any construction work. This is to minimize the maintenance cost associated with the repair of post-tension cables and reinforcing steel after construction has begun.

Ground Penetrating Radar or GPR technology is widely used to locate metallic and non-metallic structures before drilling or cutting concrete structures. The technique is quick and easy and can be used in construction projects involving private residences and office buildings. GPR is a low-risk technology and provides many benefits over other techniques. It is a non-destructive and non- disruptive process that works without affecting its surroundings.

On the other hand, concrete x-rays is quite a different technology and it requires radiation to locate solid objects underground. It has been found that it is not as efficient as GPR technology and is unable to illuminate the ground as a film is required to be placed on the opposite end in order to see through it. It is therefore only effective to be used for structures where both sides are visible and easy to get to.

In addition to this, radiography or x-rays can perform only limited scanning in one day; however, GPR can scan thousands of square feet in a short span of time. Another disadvantage of x-rays is that they are quite expensive as compared to GPR equipment. The continuous profile of the scanned line generated by GPR is very easy to understand. GPR technology can be safely used to locate areas for electrical and plumbing piping, cut wall openings for doors and windows, measure slab thickness, locate rebar and post-tension cables in concrete, and identify conduits within concrete.

Contractors prefer GPR over other concrete scanning techniques because it does not require evacuating the building. Even in crowded public areas, GPR equipment can be used without any health hazards. GPR saves time of film processing and is faster than radiography. X-rays are quite time consuming and often give inaccurate. GPR procedure is 3 to 5 times faster than x-rays. In addition, x-rays emit gamma radiations and can be harmful for the user. A single scan of x-ray requires 60 minutes; however, GPR only requires 15 minutes to perform a single scan.

Today renowned construction companies provide efficient and cost-effective concrete scanning services by conducting full scan through Ground Penetrating Radar equipment. The technology not only locates rebar, conduit, and tension cables but also helps to identify leaks and voids within the ground. Since the technology is faster and economical than radiography, the latter has become almost obsolete in today's construction industry. In addition, GPR does not require any security and therefore only one person is enough to conduct the scan.