Stabilization of Deltaic Expansive Soils Treated with Plantain Rachis Fibre and Lime

This investigative study examined the geotechnical properties of failed highway sections in the Niger Delta region of Nigeria and stabilized them using composite cementitious hybridized materials combining plantain rachis fibre and lime at various ratios (0.25% + 2.5%, 0.5% + 5.0%, 0.75% + 7.5%, and 1.0% + 10%). Natural lateritic soils were classified as A-2-6 SC and A-2-4 SM according to AASHTO classification and found to be unsuitable for road embankment construction without treatment. Results demonstrated that stabilized soils exhibited increased maximum dry density and optimum moisture content with higher additive percentages, maximum California bearing ratio improvements at 0.75% + 7.5% ratio, increased unconfined compressive strength values, and decreased plastic index properties. The composite cementitious materials proved effective as soil stabilizers for improving engineering properties of expansive deltaic soils.