NDT methods for the in-situ evaluation of pavements in the USA - a review

In this paper, the non-destructive condition evaluation of both 'flexible' and 'rigid' pavement systems is discussed. The objective is to describe non-destructive test method(s) for the in-situ, or in-place, evaluation of individual layers within rigid and flexible pavements. Such tests are: the static tests, steady-state dynamic tests, impact response tests, electromagnetic tests, and the wave propagation tests, including the ultrasonic tests, and impact testing. The characteristic that is exploited is the elastic response of materials within individual pavement layers. It is from these responses that properties, such as strength, deformation, load-carrying capacity, and locations of cracks and flaws of the overall pavement system are inferred. This work aims comprehensively at new, old, and rehabilitated pavement systems. In all of these cases, the in-site properties of layers within the pavement system are of interest; specification compliance determination, material condition monitoring, or rehabilitation effectiveness determination may follow from such knowledge.