Determining damage effects on asphalt concrete composites

Asphalt concrete (AC) is a geological composite material, which is made with different shapes and sizes of coarse and fine aggregates bonded with asphalt binder. Cohesive and adhesive damages are observed into AC. Cohesive damage initiates into the matrix material and adhesive damage initiates at the matrix-aggregate interface. Finite element method (FEM) model is developed using ABAQUS with a coarse aggregate coated with matrix material. Damage models parameters are measured in the laboratory under dry and wet conditions to simulate FEM models. It is observed that cohesive damage occurred due to increase in shear stress carrying capacity and reached to the predefined shear strength limit. Shear stress carrying capacity caused cohesive damage due to matrix material coated on circular shape aggregate. Higher cohesive and adhesive damages are observed under wet condition than that of dry condition. Irrecoverable shear strain is observed in cohesive damaged matrix materials and magnitude of this strain is significantly higher under wet condition than dry condition. Lower contact normal and shear stresses are observed at matrix-aggregate interface under wet condition than dry condition. It is believed that lower contact stresses are the driving factors of higher adhesive damage at the matrix-aggregate interface.