Research On Fatigue Damage Performance Of Asphalt Mixture By Bending Test

Fatigue cracking is one of the main failure mode of asphalt pavement. Fatigue performance of asphalt mixtures is studied, the fatigue resistance of asphalt mixture is improved which can extend the life of asphalt pavement, and save building maintenance costs, greatly improve the Social and economic benefits of road ,especially in high-grade road.In this paper, according to engineering which is from laiyuan to laishui in Zhang Shi Highway,there are three asphalt mixture including AC-l3,AC-20,ATB-30 , raw materials, mix design and pavement performance test are carried out for them. Trabecular bending fatigue test is carried out under different conditions for beam specimens of three asphalt mixtures,respectively appropriate fatigue equation is regressed, the factors including test temperature,loading frequency,type of material and intermittent time which affect the asphalt mixture fatigue life are analyzed. During trabecular bending fatigue test is carried out, strain gauge attached in different locations of specimen,and damage evolution law of compliance of specimen is obtained . the factors including test temperature, loading frequency and so on which affect fatigue damage evolution are analyzed.Based on fatigue damage theory, the overall fatigue damage state of beam specimens of asphalt mixture and the local fatigue damage state as the starting point, more in-depth studing the asphalt mixture fatigue damage mechanism, exploring the damage evolution law of asphalt mixture, and establishing a nonlinear fatigue damage model .So as to more objectively and accurately the fatigue performance of asphalt mixtures is evaluated ,and a theoretical basis for improve durability design of asphalt pavement is provided.