Strength and toughness attenuation mechanism of biobased cold-mixed epoxy asphalt under freeze–thaw cycles

ABSTRACT

Biobased cold-mix epoxy asphalt (BCEA) was prepared by adopting biodiesel and epoxy soybean oil as asphalt solvent and compatibilizer. The strength and toughness attenuation laws under freeze–thaw (FT) cycles of BCEA were studied through tensile tests, flexural tests, and dynamic mechanical analysis. The attenuation mechanism was explored through scanning electron microscopy, Fourier transform infrared spectroscopy and water absorption tests. The results showed that the first FT cycle significantly weakened the strength and toughness of BCEA. After the third cycle, the attenuation rate of storage modulus, loss tangent, and glass transition temperature of BCEA declined. The attenuation mechanism of BCEA is as follows: (1) post-curing and destruction of the cross-linking network, (2) agglomeration and aging of asphalt, and (3) diffusion and reaction of water. This research provided a theoretical basis for the application of BCEA.

KEYWORDS:

• Attenuation mechanism
• biobased cold-mixed epoxy asphalt
• freeze–thaw cycles
• strength
• toughness

Disclosure statement

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

Additional information

Funding

This work was supported by the National Key Research and Development Program of China [grant number 2021YFB2601200] and the National Natural Science Foundation of China [grant number52078191, 52008156].