This paper was presented at the `Strategic investments in structures' session. Non destructive testing methods of bridge decks using infrared thermography and ground penetrating radar have been developed for the diagnosis of the concrete condition under the waterproof membrane and the condition of the membrane itself. These very important parts of the structure suffer from constant traffic increase, climatic effects and deicing salts attack. Their condition is not visible and their ageing evolution depends not only on the service duration. This paper describes the development of a new fast scanner providing high resolution and high sensibility records of the surface temperature and visible light reflection. The vehicle containing the measurement system is driven at 10 km/h without halting the traffic. The developments of the data processing necessary for the interpretation of the scanner and ground penetrating radar measurements on bridge decks are also presented. Infrared thermography images are transformed in a plan of the bridge deck with invisible damaged zones as well as those in good condition. Ground penetrating radar gives time-depth profiles where the different layers of the structure and the defects return characteristical ecoes. The final documents contains the useful informations for organizing the maintenance of bridge decks. (A)
Samenvatting