Study On Fatigue Performance Of SMC Warm Mixing Modified Ultra-thin Abrasive Layer

The fatigue performance index of asphalt mixture is one of the important technical parameters of asphalt pavement structure design.Research on fatigue characteristics of asphalt mixture under specific traffic and environmental conditions has important guiding significance and normative role for asphalt pavement design,construction and maintenance.In this paper,the fatigue performance of Warm-Mix modified super-thin abrasive layer asphalt mixture with SMC?Styreneic Methyl Copolymers?under strain control mode is studied.In this paper,the fatigue properties of SMC warm mixing modified ultra-thin wear layer under strain control mode are studied.It provides experimental basis and theoretical basis for the application of SMC Warm-Mix modified ultra-thin abrasive layer in preventive maintenance of roads,improvement of traffic environment and improvement of road pavement function in China.Firstly,the mix proportion of SMC warm mix modified asphalt mixture is designed.The optimum asphalt-aggregate ratio of asphalt mixtures with different mix ratios is determined by using a criterion for determining the asphalt-aggregate ratio based on the most compact aggregate embedding state.The basic pavement performance of SMC warm mix modified asphalt mixture with different mix ratios was verified.By comparing and analyzing the pavement performance of asphalt mixtures with different mix ratios,it is determined that the pass rate of 4.75mm key sieve holes in the aggregate ranges from 35%to 40%.Four-point bending fatigue test was used to study the fatigue properties of SMC Warm-Mix modified ultra-thin wear layer.Several typical fatigue parameters are analyzed by test data.The results show that the change of bending stiffness modulus,normalized number product,phase angle and residual stiffness modulus ratio with cycle times presents obvious three-stage rule.Fatigue equation was established by phenomenal method and energy method to study and analyze the fatigue properties of SMC Warm-Mix modified ultra-thin wear layer.Fatigue equation was established by phenomenal method and energy method to analyze the fatigue properties of SMC Warm-Mix modified ultra-thin wear layer.The results show that the fatigue performance of SMC Warm-Mix modified ultra-thin abrasive layer asphalt mixture analyzed by phenomenological method is more suitable for the case of 50%initial stiffness modulus as the termination condition.The fatigue performance of SMC Warm-Mix modified ultra-thin abrasive layer asphalt mixture is analyzed by energy method.The results show that the cycle times corresponding to the sudden change point of dissipated energy between the second stage?RDEC₂?and the third stage?RDEC₃?are reasonable as the criterion of fatigue failure of SMC Warm-Mix modified ultra-thin abrasive layer asphalt mixture.