Reflective crack initiation of asphalt overlays on jointed concrete pavement using finite element model

ABSTRACT

In this study, a three-dimensional (3D) finite element model (FEM) consisting of an asphalt concrete (AC) overlay on top of jointed plain Portland cement concrete (PCC) slabs was developed to investigate the mechanism of the crack initiation of traffic-induced reflective cracking. Strain values at the bottom of AC overlay were the primary response obtained from the simulation results to represent the damage induced in the AC layer. Different bonding situations between the two layers, traffic load locations, material properties and thicknesses of the AC layer were taken into consideration. The analysis results show that the dominating strain for damage is dependent on the bonding condition between the AC and PCC layers. When the AC layer is completely bonded with the PCC layer, the damage will initiate firstly at the top of the joint corner between the PCC slabs to deteriorate the bonding, then the AC bottom will be susceptible to bending strain. It was observed that the most critical load location for modeling the case of fully bonded overlays is related to the AC thickness while in the case of partially bonded overlays, the most critical load location is always located on the top of one side of the PCC joint.

KEYWORDS:

• Asphalt pavement
• reflective cracking
• finite element modelling
• crack initiation

Acknowledgements

This paper presents research work that were requested and sponsored by the California Department of Transportation (Caltrans). This sponsorship and interest are gratefully acknowledged. The opinions and conclusions expressed in this paper are those of the authors and do not necessarily represent those of the State of California or the Federal Highway Administration.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contributions

The authors confirm contribution to the paper as follows: study conception and design: LJ, RW, JH; data collection: LJ, RW; analysis and interpretation of results: LJ, RW, JH; draft manuscript preparation: LJ, RW, JH. All authors reviewed the results and approved the final version of the manuscript.