Concrete Pavement Joint Diagnostics with Ultrasonic Tomography

An important issue in extending the life of jointed plain concrete pavement is the proper construction and maintenance of transverse joints. The capabilities of an ultrasonic tomography device in providing information essential to joint rehabilitation decisions as well as the quality control of rehabilitation construction are presented. Testing was conducted at various partial-depth repair locations of a recently repaired in-service highway to determine the presence and extent of debonding between the partial-depth repair and the existing concrete. Testing also was conducted at the Minnesota Road Research Facility to evaluate the subsurface condition along various transverse joints. Real-time diagnosis with the intensity-based signals of the synthetic aperture focusing technique was successful in pinpointing the location of debonded concrete interfaces within partial-depth repairs. Ultrasonic tomography testing also showed the capability of identifying that a joint is in need of repair and subsequently diagnosing the extent of subsurface deterioration throughout the joint.