Micromechanics-based analysis for predicting asphalt concrete modulus

The elastic modulus of asphalt concrete (AC) is an important material parameter for pavement design. The prediction and determination of elastic modulus, however, largely depends on laboratory tests which cannot reflect explicitly the influence of the microstructure of AC. To this end, a micromechanical model based on stepping scheme is adopted. Consideration is given to the influence of interfacial debonding and interlocking effect between the aggregates and asphalt mastic using the concept of effective bonding. Tests on asphalt mixture with various microstructures are conducted to verify the proposed approach. It is shown that the prediction is generally in agreement with experimental results. Parameters affecting the elastic modulus of AC are also discussed in light of the proposed method.