McAsphalt’s performance-graded products meet or exceed the AASHTO M 320 specification requirements and are engineered to address fundamental material properties that account for specific pavement distresses and failure mechanisms. The grade defines the temperature ranges in which the asphalt cement should not become too soft or too brittle. It is specified by climatic conditions, traffic volume and traffic type.
1987-Discussion of Employing Paving Asphalt Temperature Susceptability in Structural Design – N.W. McLeod