Mesostructural damage simulation of asphalt mixture using microscopic interface contact models

• Contact interface properties were estimated via uniaxial tension experiment.
• Macro evaluation index could not characterize properties difference in meso-scale.
• Results show mesostructural parameters have a big impact on damage characteristic.

Mesostructure and contact interface properties are important for material design and performance assessment of asphalt mixtures, which is sensitive to the crack. Conventional asphalt mixture design method always ignores the fact that mesostructure and interface significantly influence the performance of pavement. To evaluate these factors, firstly the properties of contacting interface between asphalt and aggregate were achieved through uniaxial tension test. Then numerical cohesive zone model (CZM) was utilized to estimate the crack resistance of the interface based on laboratory damage parameters. Finally, mesostructural damage simulation of asphalt mortar was conducted to unfold the entire cracking distribution, which included the contact interface properties. The results show that mesostructural parameters and interface properties have an important impact on damage characteristics. However, these factors are not comprehensively understood in current hot mixture asphalt design method.