The huge surface area of fine mineral powder particles (mostly less than 0.075 mm) makes asphalt materials form films, thus improving the bonding strength and temperature stability of asphalt materials; The locking force is mainly generated between coarse aggregate particles.
When choosing asphalt concrete mineral aggregate gradation, we should give consideration to both, so that the mixture can form a dense, stable, suitable smoothness and durable pavement after adding appropriate amount of asphalt.
Extended data:
The maximum particle size of asphalt pavement aggregate should gradually increase from the upper layer to the lower layer. The upper layer should be medium-fine, the maximum particle size of asphalt mixture aggregate in the upper layer should not exceed 1/2 of the layer thickness, and the maximum particle size of middle and lower layers should not exceed 2/3 of the layer thickness.
Stone matrix asphalt is an internationally recognized (widely used) asphalt pavement mixture with strong deformation resistance and good durability. Due to the good embedding of coarse aggregate, the mixture has very good rutting resistance at high temperature, and at the same time, due to the bonding effect of asphalt mastic, the low temperature deformation performance and water stability are also improved.