Discrete element modelling of creep of asphalt mixtures

Cai, Wei; McDowell, Glenn R.; Airey, Gordon; de Bono, John P.

Abstract

Creep tests on asphalt mixtures have been undertaken under four stress levels in the laboratory while the Discrete Element Model (DEM) has been used to simulate the laboratory tests. A modified Burger’s model has been used to represent the time-dependent behaviour of an asphalt mixture by adding time-dependent moment and torsional resistance at contacts. Parameters were chosen to give the correct stress-strain response for constant strain rate tests in Cai et al. (2013) . The stress-strain response for the laboratory creep tests and the simulations were recorded. The DEM results show reasonable agreement with the experiments. The creep simulation results proved to be dependent on both bond strength variability and positions of the particles. Bond breakage was recorded during the simulations and used to investigate the micro-mechanical deformation behaviour of the asphalt mixtures. An approach based on dimensional analysis is also presented in this paper to reduce the computational time during the creep simulation, and this analysis is also a new contribution.

Citation

Cai, W., McDowell, G. R., Airey, G., & de Bono, J. P. (in press). Discrete element modelling of creep of asphalt mixtures. Geomechanics and Geoengineering, 11(1), https://doi.org/10.1080/17486025.2015.1006689

• Journal Article Type: Article
• Acceptance Date: Jan 8, 2015
• Online Publication Date: Feb 24, 2015
• Deposit Date: May 17, 2016
• Publicly Available Date: May 17, 2016
• Journal: Geomechanics and Geoengineering
• Print ISSN: 1748-6025
• Electronic ISSN: 1748-6033
• Publisher: Taylor & Francis Open
• Peer Reviewed: Peer Reviewed
• Volume: 11
• Issue: 1
• DOI: https://doi.org/10.1080/17486025.2015.1006689
• Keywords: discrete element modelling, asphalt, creep, fracture
• Public URL: https://nottingham-repository.worktribe.com/output/744491
• Publisher URL: http://www.tandfonline.com/doi/full/10.1080/17486025.2015.1006689
• Additional Information: “This is an Accepted Manuscript of an article published by Taylor & Francis Group in Geomechanics and Geoengineering on 24/02/2015, available online: http://www.tandfonline.com/doi/full/10.1080/17486025.2015.1006689.