In the recent years NDT has been widely used in Infrastructure, new methods and equipment were developed to determine the various parameters affecting the quality of the structures.
The goal is achieving reliable information for defined problems and providing comprehensive answers about the status of the structure.
It is very important to verify the strength of the concrete and its fitness for use.
By using dedicated NDT methods the following valuable parameters can be determined:
 | Cracks |
| Concrete density |
| Surface hardness |
| Surface absorption |
| Elastic Modulus and strength |
| Delaminations, voids and segregations |
| Compliance of construction to standard requirements. |
| Reinforcing bar location, size, spacing and depth from the surface |
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Basic NDT methods for discrepancy evaluation in structures:
- Visual inspection is performed for survey and identification of structural elements and discrepancies using an advanced technology Videoscopes & Fiberscopes.
- Rebar corrosion inspection (Half cell) is used to measure the electric potential between the rebars and the concrete surface.
- Rebound hammer test is a springy electrical hammer used to evaluate the surface hardness of the concrete.
- Carbonation and chloride measurements are necessary to precisely determine the depth of carbonations and chlorides in concrete elements, as rebars are susceptible to corrosion as carbonation and chloride depth increases.
- Rebar locator inspection is used to measure the spacing of steel reinforcing bars and their diameter beneath the surface of the concrete.
- Radiographic inspection is used to detect voids, segregations, cracks in the concrete, location and spacing of reinforcing rebars, positioning of post tensioning ducts etc.
- Ultrasonic pulse velocity and pulse echo inspection is used to measure the sound velocity of the concrete, hence the compressive strength of the concrete, evaluating crack depths, delaminations etc.
- Ultrasonic Impact echo inspection is used to detect voids, cracks, delaminations, presence of grout in tendons, velocity of the concrete and more.
>GPR (Ground Penetrating Radar) is used to detect the location, position and spacing of rebars and other buried elements in the concrete.
- Infrared Imaging is used to detect voids, delaminations, water entry points for leak detection, constructive elements for restoration of construction blueprints and more.
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