Calibrated Mechanics-Based Models for Top-Down Cracking of Asphalt Pavements

This study develops a new mechanistic-empirical (ME) model to predict top-down cracking (TDC) performance of asphalt pavements. Two mechanisms including traffic contact stress and thermal stress are accounted to predict the crack increment. Paris’ law is utilized as the fracture mechanics fundamental to compute the cumulative TDC growth. The ME model consists of J-integral and asphalt mixture fracture properties, which considers the effects of traffic load spectra, layers material properties, location of crack tip, field aging, pavement structure and temperature. To facilitate the J-integral calculation, a factorial design of J-integral under different conditions is generated based on numerous finite element computations. With the aid of the database, six artificial neural network (ANN) models for different tire lengths and tire numbers and three ANN models for different coefficients of thermal contraction are constructed to predict the traffic-induced and thermal-induced J-integral, respectively. The fracture parameters can be either experimentally determined or reasonably predicted with asphalt material properties. The cumulative crack growth and number of days to reach the medium severity level are calculated mechanistically. Field performance is characterized with a sigmoidal-shaped curve, and the calculated number of days is related to the scale and shape of the performance curve for calibration purposes. It is observed that when TDC reaches a critical length, the TDC length diminishes and fatigue cracking level increases. The developed ME model is proven to be consistent with field performance, and a computer program is developed which can complete a 30-year analysis within 1 min.

  • Supplemental Notes:
    • This paper was sponsored by TRB committee AFD60 Standing Committee on Design and Rehabilitation of Asphalt Pavements.
  • Corporate Authors:

    Transportation Research Board

  • Authors:
  • Conference:
  • Date: 2019


  • English

Media Info

  • Media Type: Digital/other
  • Features: Figures; References; Tables;
  • Pagination: 7p

Subject/Index Terms

Filing Info

  • Accession Number: 01698449
  • Record Type: Publication
  • Report/Paper Numbers: 19-04423
  • Files: TRIS, TRB, ATRI
  • Created Date: Mar 2 2019 3:41PM