Mesoscale experimental procedure and finite element analysis for an indirect tensile test of asphalt concrete

Abstract

This paper describes the experimental procedures used and finite element analyses performed at the mesoscale for an indirect tensile (IDT) strength test of an Asphalt Concrete-25 Marshall specimen. The mesoscale test specimen was a three-phase composite material composed of aggregate, asphalt mastic, and void. The test results demonstrate that digital image technology combined with a finite element numerical analysis model can be used to simulate the mesoscopic damage process of asphalt concrete in an IDT test. A contactless optical system with a strain measurement accuracy of 50  was used and was a suitable method for experimentally verifying the mesoscopic strain measurements. Although the optical method provided results that were always slightly higher than those of the mesoscopic finite element method (FEM) analysis, the optical microstructure test results showed reasonably good agreement with those obtained from the FEM. Both the experimental and FEM results demonstrate that the mastic binder and interface are locations of weakness during the growth and propagation of crack damage in asphalt concrete. The study results demonstrate that the visual mesoscopic FEMs used can be an effective means for further research on the strength mechanisms of asphalt concrete at the mesoscale.

Keywords:

• asphalt concrete
• indirect tensile test
• contactless optical method
• mesoscopic finite element analysis
• strain distribution

Disclosure statement

No potential conflict of interest was reported by the author.

ORCID

Jun Fu http://orcid.org/0000-0002-5630-6776

Additional information

Funding

This work was supported by the National Natural Science Foundation of China (No. 51072149); the Chinese Department of Transportation Planning Project of Science and Technology (No. 2015319811320).