Evaluation of resilient behavior of a clayey soil with polyethylene terephthalate (PET) insertion for application in pavements base

Abstract

The growing production and consumption of PET bottles represent a major environmental problem because they end up being improperly discarded in nature or simply stocked. With the aim to attenuate the environmental problem caused by this residue, this research proposes the use of PET flakes as an alternative material for pavements base. In order to analyze the geotechnical performance of the material, physical tests, compaction and Cyclic Triaxial tests (Resilient Modulus) were carried out on pure soil as well as on the mixture of soil and PET flakes in weight percentages of 3, 5 and 7 %. The computer program SisPav (Franco, 2007) was used to perform a mechanistic-empirical design for a typical pavement structure with parameters obtained for the mixtures. The results indicated that the insertion of PET influences the mechanical behavior of the soil. It was found that resilient modulus increases, with respect to that of pure soil, for mixtures with the lowest content of PET (3%). For tests with higher contents of PET flakes, the Resilient Modulus decreases. This research concluded that the clayey soil mixed with PET flakes can be used as an alternative material for pavements base, as long as a low content of flakes is used.