Finite Element Analysis on Fatigue Cracking of Sisal Fiber Asphalt Mixture

Fatigue cracking of asphalt mixtures is the main damage phenomena for asphalt pavement, which seriously affects the pavement performance. The main influencing factors of fatigue cracking are material properties and load condition. Sisal fiber is a new road material; fracture mechanics theory and finite element method are used to detect whether sisal fiber will enhance fatigue cracking stability of asphalt mixtures. The moving uniformly distributed load is used to simulate vehicle loadings. Gradation of the mixture is AC-13, adjusted synthesis in each group as follows: basalt 1#: basalt 2#: basalt 3# : basalt 4#: slag = 20%: 32%: 12%: 35%: 1%, dosage of sisal fiber is 0.2%. ABAQUS finite element software and singular element are utilized to build the sisal fiber asphalt mixture model with cracks, as well as the common asphalt mixture. The calculated results showed that stress intensity factors of cracks for sisal fiber are reduced. The main reason is due to sisal fiber improving the modulus of asphalt mixtures. Therefore, sisal fiber can improve performance by increasing resistance to fatigue cracking.