Effects of Recycled Polyethylene Terephthalate (PET) on Stiffness of Hot Asphalt Mixtures

Abstract

In recent years, Chile’s vehicle fleet has undergone great changes, with 25% growth in motor vehicles. This increase is directly related to improvements in the performance of flexible pavements, which make infrastructure less susceptible to permanent deformations and/or cracking at high and low temperatures, respectively. In 2016, the Ministry of the Environment passed the Law on Recycling and Accountability to promote the search for innovative ideas and materials in different sectors. This research focused on the experimental study of the mechanical behaviour of a mixture of hot asphalt, incorporating thick particles of polyethylene terephthalate (PET) from bottle recycling, using the Marshall stability and flow test and the resilience module (rigidity) test at 5°C and 22°C. Based on previous research, significant PET fibre sizes were used, increasing the optimum amount of polyethylene terephthalate from 6% to 14% in the mixture. The results show that incorporating this polymeric additive provides greater stability, in addition to an increase in resistance to permanent deformations and fatigue, compared to a “traditional” mixture.