Quality Control Index for Recycled Paraffin Used as a Modifier Agent in Asphalt

Recycled paraffin is produced simply from the waste material of cross-linked polyethylene. By adding the paraffin into asphalt, its plastic flow resistance performance is improved effectively. Quality control is necessary for recycled paraffin because its properties change according to the kind of waste material. The plastic flow resistance of modified asphalt mixtures are evaluated using standard dynamic stability tests, which require great time and expense. In this paper, we develop a simple and easy method for evaluating plastic flow resistance by performing many kinds of tests and by examining the correlation between many test indexes and dynamic stability. As a result, when the kind of waste material is known, the plastic flow resistance can be evaluated suitably by measuring the softening point in a penetration test of a modified asphalt mixture, instead of using a dynamic stability test. We also show that when the kind of waste material is unknown, the quality of the recycled paraffin can be evaluated by its tensile strength and viscosity.