Computer-aided procedure for determination of asphalt content in asphalt mixture using discrete element method

Abstract

Asphalt mix design includes the determination of aggregate gradation, asphalt content and other volumetric properties, and the evaluation of mechanical properties and moisture damage potentials. In this paper, a computational method is developed to computer-aided mix design. Discrete element method is used to simulate the formation of skeleton and voids microstructures of asphalt concrete of different asphalt contents. This method takes the mechanical properties or performance of the mixture into consideration, such as inter-aggregate contacts and local stability. A simple visco-elastic model is applied to simulate the contacts between asphalt binder and aggregates. The surface texture of an aggregate particle can be taken into consideration in the inter-particle contact model. For a certain air void content, the mastics volume, binder volume or the asphalt content can be determined via a digital compression test. The asphalt content can also be determined using an alternative approach that is based on modelling the inter-particle contact with an asphalt binder layer.

Keywords:

• Discrete element method
• Asphalt content
• Asphalt mix design
• Visco-elastic model
• Compression test

Acknowledgement

We would like to thank Dong Wang, Wenjing Xue, Wenjuan Sun and Yinning Zhang for their help on testing and sample preparation.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was supported by the National Science Foundation [grant number CMMI 1000172].