A
gradation method of a small-grain-size skeleton dense type
asphalt mixture comprises the following steps: 1, determining boundary
sieve holes of a main skeleton and filling aggregates; 2, according to a
gradation filling theory, obtaining the composition
mass ratio of each grade of filling aggregates; 3, determining the optimum
mass ratio of each grade of filling aggregates; 4, adopting a
grey correlation entropy
analysis method to determine key
sieve holes which influence the skeleton properties of the
asphalt mixture according to the influence of each grade of filling aggregates on the
clearance rate and the maximum bearing capability of the main skeleton; 5, obtaining the
gradation optimal range of the main skeleton of the
asphalt mixture; 6, determining the
mass ratio of each grade of filling aggregates; 7, determining key
sieve holes that the filling aggregates influence the performance of the small-grain-size asphalt mixture; 8, obtaining the gradation
reference range of filler in the asphalt mixture; and 9, determining the ratio of the main skeleton to the filling aggregates through a volumetric method so as to obtain the gradation range of the small-grain-size skeleton dense type asphalt mixture. The gradation method enables the skeleton and the dense state of the mixture to simultaneously reach the optimum and meets the requirements of roads and anti-slip performance.