Applications of State of the Art NDT Techniques in Bridge Inspections

This article introduces the author's accumulated experience in applying state of the art NDT techniques in bridge special inspections. The NDT techniques and their applications introduced in this paper, including some examples from actual bridge inspections, are the Ultrasound Tomography, Impact‐Echo and Impulse‐Response. The main applications of those systems in bridge special inspections are in evaluation of post‐tensioned bridges' ducts' injection as the prestressing system is an internal system embedded inside the concrete structure, in integrity evaluation of road bridge decks surface structures (especially with asphalt pavement) and in detection of hidden faults and damages inside concrete structures. The main objective of a bridge special inspection is to evaluate the condition of a bridge by onsite testing, sample taking and laboratory examinations. Regular inspection techniques yield only limited results. Reliable data from the inspection is required for repair planning and for setting its logical timing and for ensuring the bridge safe usage. Suitable NDT techniques significantly assist in overcoming the downfalls of regular inspection techniques and in ensuring bridges' safe use, as the author has proven in large number of cases.