Subgrade Improvement With Recycled Polymer (PET) in Clay Soils for Rural Roads

Abstract

The project provides information on the physical and mechanical properties of clay soils stabilized with recycled polymers (PET) as subgrade improvement in rural roads in the district of Sicaya, because this area does not have paved roads nearby which cause inaccessibility to the population; also by using PET for soil improvement, an added value was given to this material generating a lower environmental impact. In order to fulfill the objective of the research, the physical properties of two soil specimens from Jr. La Libertad in the district of Sicaya were determined; sieving tests of granulometry, consistency limits, modified proctor and soil classification by SUCS and AASHTO were performed. Once the soil properties were evaluated, the optimum size of the PET particles for its application was determined by CBR tests using 1% of PET as a proof. It was found that the optimum size was from 5 mm to 10 mm, and to find the optimum percentage of polymers to be applied, four percentages of recycled polymers were used: 0.5%, 1.0%, 1.5% and 2.0%; these percentages were proposed for the two specimens analyzed. It was obtained that the percentage of 1.5% was the one that provided the highest CBR index, having 7.15% and 4. 87% of CBR at 95% compaction for the first and second specimen respectively; the latter turned out to be lower than the 6% CBR required as a minimum by the Highway Manual, and this was because the second specimen presented more fine material than the first specimen having a high value of 77.77%, which is not recommended for using recycled polymers according to this research.