Consensus requirements” came about because SHRP did not specifically address aggregate properties and it was thought that there needed to be some guidance associated with the Superpave mix design method. Therefore, an expert group was convened and they arrived at a consensus on several aggregate property requirements – the “consensus requirements”. This group recommended minimum angularity, flat or elongated particle and clay content requirements based on:
The anticipated traffic loading. Desired aggregate properties are different depending upon the amount of traffic loading. Traffic loading numbers are based on the anticipated traffic level on the design lane over a 20-year period regardless of actual roadway design life (AASHTO, 2000b[5]).
Depth below the surface. Desired aggregate properties vary depending upon their intended use as it relates to depth below the pavement surface.
These requirements are imposed on the final aggregate blend and not the individual aggregate sources.