By Amma Wakefield, P.Eng.
Asphalt mix design is a delicate process of choosing and balancing the appropriate aggregates, asphalt binder and their proportions to obtain an asphalt mixture that is deformation resistant, fatigue resistant, low temperature crack resistant, durable, moisture damage resistant, skid resistant and workable.
The quality of the asphalt mix and its ability to perform is evaluated through set parameters for aggregates, asphalt binder, recycled materials and volumetric properties such as: Air voids (Pa), Voids in Mineral Aggregate (VMA), Voids Filled with Asphalt (VFA), and dust proportion. The parameters are set because they have historically provided a good indication of a mixture’s probable performance.
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