Mechanical Behavior Analysis of Asphalt Chip Seals Based on the Microstructure

Based on the microstructure, a two-dimensional finite element model for asphalt chip seals was built to analyze the mechanical behavior under vertical loads. The results show that the vertical displacement of stones in chip seals at the inner edge of the wheel is the maximum and the rotation angle is the minimum. On the contrary, the rotation angle of the stones at outer edge of the wheel path is the largest, and gradually decreases from the outer edge to two sides. The horizontal strain in asphalt binder is mainly compressive strain. The maximum shear strains at the outer edge of wheel path exist at the interface between asphalt and asphalt mastic. The horizontal deformation and shear deformation at the aggregate-asphalt interface are higher than in asphalt binder. The maximum Mises stress is on the interface at the stone-asphalt and the greater shear deformation is in asphalt mastic under the stones, which easily lead to shear failure on the asphalt chip seals.