Evaluation of Damage to Asphalt Pavements using a Micro-focus CT Scanner and Three-dimensional Crack Analysis

Longitudinal cracking has become increasingly common in asphalt concrete pavements worldwide since the introduction of modified bituminous binder to reduce rutting. This study extracted sample cores from two road sections (A and B, using a diamond cutter) from a motorway pavement which had been in service for five years and was showing no cracks (A) or longitudinal cracking on the surface (B). Further, cores for each layer of new and damaged sections were analyzed for the types of cracks using a newly developed microfocus CT scanner (CT) and a three-dimensional (3D) crack analysis program and the study obtained failure limits (new concept) for each layer. The study found that the results can be applied to the pavement of both sections (A and B) in service, and that it is effective for a direct evaluation of pavement damage and can be applied to diagnose the degree of 3D damage in asphalt pavements.