Classification, Characteristics and Application scope of Asphalt Pavement
According to technical quality and the use of commonly used class of asphalt pavement can be divided into concrete, hot mix asphalt gravel, asphalt penetration type, and asphalt surface treatment 4types.
Characteristics of various types and application scope is: asphalt concrete pavement: Strength is dense built according to the principles of composition.Using high-quality asphalt, it is the consistency of asphalt pavement in high demand also take thick.Another outstanding feature is using considerable amount of slag.High adhesion makes road has a very high strength, can withstand relatively heavy vehicle traffic。But allowance of tensile strain is small , transverse cracks will rule industry, which requires a strong base asphalt concrete pavement. High temperature stability and low temperature stability are requirements. Smaller porosity asphalt concrete pavement having small water permeability, good water stability, high durability and a greater ability to resist natural factors, work life can be at least 15 - 20 years.Asphalt concrete pavement is suitable for highway and first secondary road surface.Hot mix asphalt macadam pavement: high temperature stability, the road is not easy to produce waves, cold winter is not easy to produce shrinkage cracks, small cracks under traffic loads;Hot mix asphalt macadam pavement: high temperature stability, the road is not easy to produce waves, cold winter is not easy to cause shrinkage cracks,less small cracks under traffic loads；easier to maintain a rough road, it is conducive to high-speed driving； Gradation of stone and asphalt specifications wider, easier to meet the requirements of material combination； less asphalt use, no slag and low cost.Hot mix asphalt macadam suitable for roads in general, not for highway. Medium-grained and coarse asphalt macadam asphalt concrete surface layer is preferably used as the lower, the coupling layer or a leveling layer.
Asphalt penetration formula: Strength and stability of penetration pavement wedging effect mainly consists of stone with each other. Penetration pavement require 2-3 weeks of forming, rolling and driving under the influence of gravity, the gradual infiltration of asphalt wrapped in stone, filling the voids form an integral layer of a stable structure, good temperature stability, the passage of a hot day should not appear, Yong package, cold weather should not crack occurs at low temperature, the uppermost penetration pavement should seal layer material or spreading overlay mixing layer. Asphalt penetration formula applies to secondary and tertiary roads, but also as asphalt concrete surface layer coupling layer. Asphalt Surface Treatment: Treatment can improve the surface of the asphalt road driving conditions, traffic wear and assume the role of the atmosphere, extending pavement life. The paving asphalt, the thickness may be greater than 3 cm. In calculating the thickness of the road surface, the intensity is generally not counted. Treatment asphalt surface, generally used for tertiary roads, also be used as asphalt pavement wearing surface, non-slip layer.