HYDRAULIC CONDUCTIVITY OF FINE-GRAINED SOILS STABILIZED WITH PLANTAIN PEEL POWDER AS PARTIAL REPLACEMENT FOR LIME

This study investigates the effects of plantain peel powder (PPP) as a sustainable stabilizing agent on the geotechnical properties of two clayey soils obtained from Mandate Lodge (MC) and Ora-Ayoka (OAC) in Kwara State, Nigeria. Laboratory tests, conducted according to BS 1377:1990, evaluated the Atterberg limits, compaction characteristics, California Bearing Ratio (CBR), and hydraulic conductivity at PPP contents of 1–10% by weight of dry soil. The Mandate clay exhibited higher natural moisture content (19.22%) and specific gravity (2.78) compared to Ora-Ayoka clay (11.95% and 2.66). Both soils were well graded. The liquid and plastic limits decreased progressively with increasing PPP, indicating reduced plasticity and improved workability. Maximum dry density decreased while optimum moisture content increased, attributed to PPP’s low specific gravity and filler nature. CBR values improved with moderate PPP inclusion, peaking at 4% for MC (64%) and 6% for OAC (36%), before declining due to excess organic matter. Hydraulic conductivity decreased with increasing PPP, signifying enhanced impermeability. Overall, plantain peel powder at 4–6% replacement effectively enhanced soil strength and reduced permeability, promoting sustainable reuse of agro-waste in geotechnical applications.