Method for improving aging performance of asphalt pavement material through layered modification

The method comprises the following steps: 1, taking an upper surface layer and a middle surface layer of a to-be-studied asphalt pavement as a whole, and sequentially dividing the whole into a first layer material, a second layer material and a third layer material downwards in the depth direction by taking the surface of the upper surface layer as a reference; 2, adding an additive which accounts for 2%-12% of the mass of the asphalt cement and is formed by compounding an ultraviolet radiation aging resistant agent and a strong thermal oxidation aging resistant agent into the first layer of material, wherein the mass of the additive accounts for 2%-12% of the mass of the asphalt cement; 3, adding an anti-thermo-oxidative aging agent which accounts for 1-8% of the mass of the asphalt cement into the second layer of material; and 4, adding an anti-thermal aging agent which accounts for 0.5%-5% of the mass of the asphalt cement into the third layer of material. The method can improve the aging resistance of the