Nondestructive Testing

The Bridges and Structures Bureau at the Iowa Department of Transportation is responsible for evaluating and maintaining the primary bridge system. The bureau uses various testing procedures to evaluate the condition of the structures. Nondestructive testing (NDT) is used to evaluate the properties of a material without causing damage. 

Common NDT methods may rely upon use of electromagnetic radiation, sound, and inherent properties of materials to examine samples. NDT incorporates all the technology for detection and measurement of significant properties, including discontinuities. This provides the means by which structures may be inspected without disruption or impairment of serviceability.  NDT has become an increasingly vital factor in the effective conduct of research and design and is a highly-valuable technique that can save both money and time.

Iowa DOT is investigating the use of ground penetrating radar (GPR), impact echo (IE), ultrasonics (UT), half-cell potential (HP), electrical resistivity, and others for detecting various levels of deterioration in bridge decks.