road works;  asphalt mixture;  strain-life fatigue equation;  Fatigue cracking

Based on the research results at home and abroad, reasonable and feasible conditions such as specimen size, failure criterion, control mode, loading frequency and test temperature in the direct tensile fatigue test of asphalt mixture are proposed. Based on the fatigue test results of different strain levels, the average stress influence is analyzed, and the strain-life fatigue equation of asphalt mixture is established, which can be used as the basis for estimating the fatigue cracking life, and the threshold value and limit value of fatigue cracking tensile strain of asphalt mixture are proposed. The strain-life fatigue equation obtained by direct tensile fatigue test of asphalt mixture can better reflect the fatigue characteristics of asphalt mixture, and the threshold and limit values of fatigue cracking tensile strain can fully reflect the fatigue failure process of asphalt mixture.