Study On Visco-elastic Property Of Fiber Reinforced Asphalt Concrete

The highway construction develops rapidly over years in China, and the total mileage of highway has already occupied the second place of the world. On the other hand, it is difficult to reach its designed life for most of the asphalt pavements due to the early damage of highway. Fiber reinforced asphalt concrete compared with ordinary asphalt concrete has better performance and the addition of fiber can decrease crack and increase the life of pavement. All of these advantages of fiber reinforced asphalt concrete have been realized in many tests and projects.Based on the theory of micro-mechanics and visco-elastic mechanics, this paper works at the research of relax modulus of fiber reinforced asphalt concrete, the visco-elastic solution of effective modulus for fiber asphalt concrete has been established. The influence of fiber on Poisson's ratio of asphalt concrete using elastic and visco-elastic theory has been discussed, and the relax properties of several common fibers reinforced asphalt concrete are analyzed. Specimen and pavement model of fiber reinforced asphalt concrete have been set up by means of ABAQUS based on the visco-elastic solution of effective modulus for fiber reinforced asphalt concrete. The response of asphalt concrete and fiber reinforced asphalt concrete under static and dynamic period load is analyzed. The effect of static and dynamic creep property of asphalt concrete on road deflection is studied in 45℃.The comparison of the theoretical solution from the proposed equation and the experimental data shows good consistency at the fiber content less than 0.20%. The Poisson's ratio increases with the decreases of relax modulus during the process of relaxation for fibers reinforced asphalt concrete. The deformation of asphalt concrete specimen under half rectangle periodic load is smaller than that under static load. Creep deformation of asphalt concrete has remarkable influence on the deflection of pavement under static and dynamic load. The use of fiber can obviously reduce the deformation of pavement for static load. The deformation of asphalt pavement under half rectangle...