Turning textile waste into sustainable solutions: Enhancing earth embankment repair with fibre treated soils

The textile industry produces a substantial amount of waste, contributing significantly to environmental issues. Most of this waste ends up in landfills or is incinerated, highlighting the need for more efficient waste management solutions to enhance circularity. At the same time, the construction and geotechnical industries play a significant role in the circular economy paradigm, as they are potential recipients of waste materials. In fact, in In recent decades, textile fibres in the form of threads or filaments of diverse size and properties have been used as reinforcing inclusions in treated soils, earth embankments and slopes. Starting from this twofold background, this study investigates the use of natural linen and viscose textile fibres derived from industrial waste in sandy silt soils commonly used in levees. To conduct the research, an experimental laboratory-scale approach was adopted with the aim of defining the appropriate soil-fibres mixture proportions and comparing physical properties and mechanical behaviour of natural and treated soil. The findings indicate that incorporating textile fibres alters soil compaction properties by lowering the maximum dry density and increasing the optimum water content. Furthermore, the presence of fibres can significantly increase soil ductility and shear resistance; however, the effect is highly dependent on the filaments’ nature, quantity and geometry, i.e. diameter and length. As the results demonstrate that the geotechnical properties of the treated soil can be engineered to meet specific site requirements, the proposed approach seems a promising solution for earth embankment repair.