Geotechnical properties of some selected lateritic soils stabilized with cassava peel ash and lime

Abstract

This study presents the influence of cassava peel ash (CPA) and lime on some geotechnical properties of three lateritic soils. This is with a view to the use of locally available agricultural waste in stabilising lateritic soils. Soil samples (termed A, B, and C) were collected from three different locations in Osun state, South West, Nigeria. Some properties such as particle size distribution, liquid limit (LL), plastic limit (PL), Compaction properties (optimum moisture content, OMC and Maximum dry density, MDD), California bearing ratio (CBR) and unconfined compressive strength (UCS) of the soil samples were determined. Cassava peel collected from a cassava processing factory was calcined at 700oC and CPA produced was sieved through sieve No. 40. Different percentages, 2, 4, 6, 8% (by weight of dry soil) of CPA and a fixed percentage (4%) of lime were mixed with the lateritic soil. Lime was added to supply calcium ion (Ca2+) needed for formation of Calcium Silicate stabilising compounds. The LL, PL, OMC, MDD, CBR and UCS of the stabilised soil samples were determined. There was a general improvement in the geotechnical properties of the soil (especially samples A and B) with about 20% reduction in LL, 38% increase in CBR, 120% increase in UCS. The study revealed that a combination of CPA and lime has the potential of improving the geotechnical properties of fine grained lateritic soil