Assessing the Potential Improvement of Fine-grained Clayey Soils by Plastic Wastes

Because of progressively dumping of plastic wastes (PWs) obtained from beverage industry it is of interest to use them as reinforcement material in civil engineering projects. For assessing potential use of plastic wastes in improvement of shear strength of fine-grained soils, two clayey soils were mixed with different amount of plastic wastes (i.e. 0.5%, 1.0%, 1.5% and 3.0% by weight) and consolidated undrained triaxial tests were performed on the compacted samples. Test results indicate that variations of shear strength and pore water pressure depend on the amount and type of plastic waste. It is observed that, irrespective of clay plasticity, adding plastic waste to the fine-grained soils improves their shear strength and plastic waste content (PWC) of 3.0%, within the range of used amounts, has the best effect on the shear strength. Moreover, adding plastic waste causes to decrease shear-induced pore water pressure slowly. Furthermore, deformability of samples changes in term of plastic waste content, type of plastic and clay type. It can be concluded that there is a possible usage of clay-plastic waste mixtures as construction materials and, thereby, plastic wastes can be managed by recycling them in the field of geotechnical engineering, thus contributing to clean up the environment.