Characterisation of the mechanical performance of asphalt concrete mixtures with selected WMA additives

ABSTRACT

Warm mix asphalt (WMA) has been introduced along with the efforts towards the construction of sustainable pavements. Numerous research studies investigated the performance of WMA in terms of moisture sensitivity and cracking susceptibility. However, the effect of WMA additives on the mechanical properties of asphalt concrete (AC) mixtures in compression state is not as thoroughly investigated. Thus, there is a need for the assessment and realistic prediction of the performance of WMA mixes, especially in the compression state (rutting). The main objective of this study is characterising mixtures with various WMA technologies and assessing their performance in comparison with hot mix asphalt (HMA). This is carried out mechanistically through viscoelastoplastic continuum damage (VEPCD) modelling in compression state. The VEPCD model, which is originally developed for HMA, is shown to be sensitive and applicable for the characterisation and assessment of WMA. The results show that the effect of WMA additives on the mechanical performance of AC varies depending on the type of the WMA additive. It is portrayed that there is an interaction between the types of WMA additive and the asphalt binder revealing that the effect of one additive might differ depending whether the binder is neat or polymer modified.

KEYWORDS:

• Warm mix asphalt
• viscoelasticity
• viscoplasticity
• pavements
• sustainability

Acknowledgements

The statements made herein are solely the responsibility of the authors.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This work was made possible by the NPRP award [NPRP 5-506-2-203] from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.