Abstract:
Management of waste plastic bottles is one of the major environmental challenges in the world. Plastic bottles are composed Polyethylene Terephthalate (PET) which is non- biodegradable and causes environment problems. Various studies have been carried out on use of waste plastic bottles in the form of custom-made strips as stabilizer however, no significant research has been carried out on use of waste plastic bottles shreds already available in the market. These shreds do not require any special technology or arrangement to produce in bulk quantity for commercial use as soil stabilizer. In this study, locally available plastic shreds prepared from waste plastic bottles were used to stabilize low plastic silty clay. Standard proctor test and direct shear tests were carried on soil stabilized with 3 different size plastic shreds (2 mm, 6 mm and 10 mm) and in four different concentrations (1%, 3%, 5% and 10%). The result showed that the maximum dry density (MDD) decreased while optimum moisture content (OMC) increased with increase in plastic content and shred size. An increase of 10.2% in angle of internal friction of soil was observed with inclusion of 2 mm shred in 1% concentration then no significant increase beyond this percentage. There was less significant increase in cohesion for 2 mm shred in 1% concentration while decrease with increase in shreds concentration and size. It was concluded that mixing waste plastic shreds with soil in 1% concentration improves the shear strength of the silty clay soil along with reduction in non-biodegradable plastic waste.
