Characterization of Asphalt Concrete Deterioration Using Monotonic and Cyclic Tests

Abstract

A viscoelastic continuum damage mechanics (CDM) model is used to assess whether or not it would be possible to predict fatigue characteristics of asphalt concrete mixtures by the aid of experimental results obtained using monotonic tests. The CDM-model is shown to effectively eliminate strain rate dependence at monotonic testing and strain and stress amplitude dependence as well as mode of loading dependence of fatigue testing. The model is also shown to be able to model effects of different temperatures by the use of the time-temperature superposition principle, at least under conditions of not too low a stiffness. However, based on the results presented, it is difficult to accurately predict fatigue results based on characteristic curves obtained from monotonic tests under all testing conditions. The reason may be difference in damage mechanisms of the two types of loading (monotonic vs. cyclic).

Keywords:

• Monotonic testing
• Fatigue testing
• Asphalt concrete
• Time-temperature superposition
• Damage mechanics

Acknowledgements

The research described in this paper was carried out with financial support from the Swedish National Board for Industrial and Technical Development (NUTEK), today part of the Swedish Agency for Innovation Systems (VINNOVA) through the Road/Bridge/Tunnel (Väg/Bro/Tunnel) consortium. Nynäs AB are greatly acknowledged for providing testing materials.