Detection of Dynamic Modulus and Crack Properties of Asphalt Pavement Using a Non-Destructive Ultrasonic Wave Method

Non-destructive ultrasonic testing has attained popularity due to its robustness and cost-effectiveness in monitoring the structural health and performance evaluation of pavements, thus replacing traditional methods. This paper presents the application of an explicit finite element method for the modeling of ultrasonic wave propagation through asphalt concrete. Prior to modeling, non-destructive ultrasonic testing was conducted on four different types of asphalt concrete (AC-13, SMA-13, AC-20, and AM-20). Based on acoustic information (wave velocity) obtained in non-destructive testing (NDT) and density, the dynamic moduli of these asphalt concretes were evaluated and used in numerical modeling of ultrasonic wave propagation using the commercial software package ABAQUS. The ultrasonic wave results obtained by numerical modeling were compared with experimental results. This comparison showed a good fit between the finite element (FE) results and the experimental results and confirmed a good FE approach for ultrasonic wave propagation. In addition, the influence of varying dynamic moduli, density, varying location, and crack size/depth on ultrasonic wave propagation was analyzed.