Top-down cracking depth assessment in asphalt pavements using ultrasonic testing

Abstract

A procedure for on-site identifying, monitoring and control of top-down propagated cracks in asphalt pavements is proposed, allowing precise and high-performance evaluation of the extent and depth of surface-initiated cracking by using ultrasonic techniques, and making it possible to apply this methods for pavement management systems. The methodology has involved the previously analytic deduction of theoretical models that simulate ultrasonic wave propagation ratios, subsequently calibrated using the experimental results from laboratory and on-site measurements, providing generalized mathematical expressions and charts for routine use in practical applications. The results have demonstrated that the proposed non-destructive methodology-cost-effective, fast and easy-to-implement-can be applied with sufficient reliability and repeatability to asphalt pavements. The maximum average relative error of the crack depth estimated by the proposed models is lower than 13% (with a confidence level of 95%).