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The service life of asphalt pavement is influenced by many factors, of which the properties of asphalt binder are the most important. The self-healing properties of asphalt binder counterac...

Previous research has proved that paraffin has a negative effect on the mechanical properties of asphalt binder; however, until now there are very few studies on the fundamental mechanisms ...

Piezoelectric energy harvesting in pavement is an advanced energy saving technology. It is carried out by laying the piezoelectric material in the pavement structure and converting the mech...

Cracking failure in asphalt binder in winter has always been one of the most serious problems in pavement structures. Classical fracture mechanics is the most widely used method to analyze the initiation and propagation of cracks. In this paper, a new modeling and computational tool—namely, the phase-field method—is proposed for modeling the Mode I cracking failure in asphalt binder. This method describes the microstructure using a phase-field variable that assumes 1 in the intact solid and −1 in the crack region. The fracture toughness is modeled as the surface energy stored in the diffuse interface between the intact solid and crack void. To account for the growth of cracks, a nonconserved Allen-Cahn equation is adopted to evolve the phase-field variable. The energy-based formulation of the phase-field method handles the competition between the growth of surface energy and release of elastic energy in a natural way: the crack propagation is a result of the energy minimization in the direction of...

The self-healing mechanism of asphalt has always been a challenging issue for pavement engineers; up to now there is no general agreement on the fundamental mechanism. In this paper, combined with atomic force microscopy (AFM) technology, the self-healing mechanism of asphalt is simulated by using the phase-field model in two ways: thermodynamic approach and mechanical approach. In the thermodynamic approach, self-healing is considered as a material-phase-rearrangement process. Microcracks will form and disappear in the stress concentration zone near the phase interfaces because of phase separation, which is demonstrated by AFM results. In the mechanical approach, the microstructure is described using a phase-field variable that assumes a positive field in the intact solid and negative one in the existing crack void. Allen-Cahn dynamics are adopted to evolve the phase-field variable that the surface energy will result in the wetting of two surfaces and finally leads to self-healing. By using both ...