Geotechnical and engineering properties of expansive clayey soil stabilized with biomass ash and nanomaterials for its application in structural road layers

Clayey soils often pose issues such as swelling, high plasticity, low permeability, and low bearing capacity, particularly in regions with seasonal rainfall. Consequently, soil improvement techniques are necessary for constructing road base layers. Currently, the most used method for road stabilization involves the application of traditional binders such as lime and cement. However, the production of cement and lime has negative environmental impacts and depletes natural resources. In this study, new stabilizing materials based on waste and by-products, as well as a new generation of nanomaterials, are investigated for stabilizing highly plastic and expansive soils. The geotechnical and mechanical properties of soils stabilized with waste materials like biomass ashes from electricity generation, along with small amounts of a silica-based nanotechnological stabilizer, are examined. The obtained results suggest the potential reduction in the use of traditional binders by incorporating by-products, while still maintaining soil properties, and even improving the properties through the application of nano-sized additives. (c) 2023 Elsevier Ltd. All rights reserved.