Journal of the Korean Asphalt Institute ISSN:2234-0785(Print) 2635-9553(Online) 한국아스팔트학회지

Asphalt grading is to provide necessary information in selecting the appropriate asphalt for construction of asphalt pavements having desired performance properties. For this purpose, United States has developed the PG- grading in the middle of 1990 and it is used in practice since then. Recently, this PG-grading has been accepted as the domestic binder grading specification, but its effectiveness has never been properly evaluated. The purpose of this study lies in critically analysing the PG-grading and suggesting the method of resolutions, if any problems exist. The present PG-grading contains the upper (rut-resistance) and the lower(low temperature crack resistance) grading. The result of analysis indicates that the upper and the lower grade, both, contain serious errors. It is suggested that the low-temperature fracture test for the lower grade and a new theoretical grading equation for the upper are suggested as an alternative solution. Rationalization of these propositions are validated by using asphalt and mixture property data found in literature