What we do 

 INTRODUCTION  back to presentation


Most modern buildings, bridges, tunnels, piers and many monuments are made using reinforced concrete structures. The strength of these structures depends on the quality of the concrete and on the number, size, position and condition of the reinforcements, which may be steel bars (the so called rebars) or tensioned steel cables. In recent years it has become increasingly necessary to inspect reinforced concrete structures. As they age, possible steel corrosion can affect their safety, and documentation is often missing when considering the modification or “recycling” of older structures. Non-destructive inspections are obviously preferable, but rarely used and often considered difficult or impossible.

THASA provides non-destructive testing for reinforced concrete structures that were too difficult or too expensive to evaluate until now.

We combine X-ray-type imaging, familiar to everybody from medical applications, with triangulation techniques commonly used by surveyors to locate objects. Instead of normal X-rays, we use more penetrating radiation such as gamma rays. Thus we generate radiographic images we call gammagraphies to obtain for example two or more perspective views of hidden rebars. With our software we then analyze the images and are able to tell where the rebars are, what their diameter is and if they are corroded. At the same time we see any voids or “concrete honeycombing”.

Such measurements have been performed before, but not in the systematic, original and standardized ways we have developed over many years of experience and innovation. The result is totally unprecedented precision and reliability, and the application to structures previously considered inaccessible to these techniques. Our main proprietary innovations are in precise inspection hardware with new fiducial mark generation, image enhancement through radiation filtering and sophisticated analysis and simulation software. We are continually involved in further developments to take advantage of new technologies such as those being developed for digital imaging, data handling and transmission and new detectors.

Our approach to the inspection of reinforced concrete structures is the only practical non-destructive technique available for the detailed and precise study of deep and/or complex reinforcements. Compared to destructive studies, much more comprehensive inspections can be performed, while at the same time avoiding damage, noise, dirt, dust and disruption.

We are expanding our services around the world in partnership with local engineering and non-destructive testing (NDT) companies.