Fatigue cracking of viscoelastic asphalt composite materials is one of the major distresses in asphalt pavements. To quantify the weakening effect of the fatigue cracks on the mechanical properties of the viscoelastic asphalt composite materials, this study takes an asphalt-filler composite system as an example, and micromechanics models are proposed by combining Eshbely's equivalent inclusion theory and Mori-Tanaka approach. Dynamic shear rheometer (DSR) tests are performed on the viscoelastic asphalt-filler composite systems with two volumetric contents of inclusion (10% and 27%) at different frequencies (0.1–100 Hz), temperatures (15℃, 20℃, 25℃) and strain levels (0.01%-0.1% for nondestructive DSR tests; 5%, 6%, 7% for destructive DSR tests). Results show that the predicted shear modulus results by a modified viscoelastic strengthening coefficient (VSC) model match with the test results at both low and high filler contents. Then a viscoelastic strengthening coefficient with fatigue cracks (VSC-f) model is proved being capable of accurately predicting the shear modulus for the viscoelastic asphalt-filler composite systems at different strain levels, temperatures, filler contents and damage levels. Both the VSC and the VSC-f model are derived to be dependent of loading frequency, temperature and filler content, but independent of strain level.
Bibliographical note© 2021 The Authors. Published by Elsevier Ltd. This is an open access article under the Creative Commons Attribution 4.0 International (CC BY 4.0).
Funding: This research was supported by Ministry of Science and Technology, P. R. China, via the National Key Research Project under Grant No. 2019YFE0117600 and Zhejiang Provincial Natural Science Foundation of China under Grant No. LZ21E080002. This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement DIMMs No 846028.
- Viscoelastic asphalt composite system
- Eshbely’s equivalent inclusion theory
- Fatigue crack
- Eshbely's equivalent inclusion theory
- Viscoelastic asphalt-filler composite system
- Complex Poisson's ratio