Incorporating plastic waste fibres for sustainable sandy soil

Abstract

The increase in urbanization has led governments to build on sites with certain geotechnical ‎hazards, such as liquefaction, ‎low bearing capacity, etc. In recent decades, as governments ‎have focused their efforts on the environmental and ‎economic aspects, researchers have ‎emphasized the need to use suitable alternative materials for the best design features, also the issue of plastic pollution is a significant global problem that requires urgent attention, current initiatives focus on the use of technical solutions to integrate non-biodegradable plastics into ‎the construction of buildings and road pavement.‎ ‎In this ‎paper, a series of direct shear tests were performed to evaluate the benefits of plastic wastes, ‎such as polypropylene ‎‎(PP) pots, and the engineering properties of sand reinforced with such ‎materials. To highlight the contribution of the ‎reinforcement to the shear strength, the ‎tests were carried out on sand reinforced with variable fibre contents (0.2, 0.4, 0.6, ‎and 0.8%) ‎for loose-density sand and medium-density sand. ‎ The experimental results showed that the increase in shear ‎strength is relatively more significant for specimens prepared with dry deposition mode as compared to those prepared ‎with wet deposition mode and it is increased with the fibre content. The inclusion of randomly distributed fibres has a significant effect on the shear strength and dilatation of sandy soils. Furthermore, the recycling fibre used in this study ‎shows a better performance in terms of shear strength. In conclusion, the use of plastic waste as ‎reinforcement would lead ‎to at least two solutions: soil reinforcement and reducing the ‎environmental impact of waste.