Segregation of asphalt pavement is a guiding surface area in the asphalt mixture material properties are uneven, including asphalt content, gradation composition, additive content and surface porosity, which accelerated the damage of asphalt pavement. Some of expressway asphalt pavement early damage, such as caused by damage to the water net crack, deformation and potholes, local serious rut depth, local bleeding, transverse crack, a new shop asphalt pavement structure depth and unequal, and the asphalt mixture segregation related.
From a macro perspective, there are basically three types of segregation of hot mix asphalt mixture:
(1) the gradation segregation in hot mix asphalt material production, transportation, sharing shop in the process of improper operation caused by set of mixture of coarse and fine material distribution and segregation. More coarse aggregate of asphalt pavement void rate is larger, and the asphalt content low lead to the loss of water damage and durability of asphalt pavement generation, resulting in fatigue cracks and holes and peeling and other diseases; fine aggregate are more concentrated in the area of asphalt pavement a small percentage of voids and asphalt content high, prone to rutting, bleeding and other diseases.
(2) the temperature segregation in hot mix asphalt material in the process of transportation, paving, due to the different positions of the mixture temperature does not drop consistent, resulting in mixture temperature difference, temperature segregation. Mixture lorry surface mixture, lorry carriage on both sides of the paver, the two wings of easy to produce temperature segregation.
(3) set of material of asphalt segregation oil content larger mixture easy happening this kind of segregation, similar to the analysis of the asphalt mixture leakage, SMA mixture is easy to produce the separation.
