Abstract
In this data, the effect of locally available additive Coconut shell powder (CSP) substitute in determining the geotechnical properties of Ado Ekiti soil was assessed. The samples were collected from two borrow pits, Ado-Ijan road and Ado-Ilawe road, at two points each, and were treated using substitute of coconut shell powder, considering several percentages of its content at 0%, 2%, 4%, 6%, 8% and 10%. Laboratory tests such as specific gravity, consistency limit test, grain size distribution test, compaction test, CBR test, triaxial compression test, permeability test was conducted on the soil samples collected, and untreated soil was determined. The summary shows that the liquid limit, plastic limit, Plasticity Index, Maximum Dry Density and Optimum Moisture Content increases with increase in percentage of the additive and later decrease at higher percentage of additive, mostly at 8% and 10% respectively. The value of California Bearing ratio in percentage increases as the percentage of additive increases, although at 0% additive, the soil does not meet specification of road construction and the value of permeability 'k' also increases. The summary of triaxial test also shows increase in the strength properties of the soil at certain percentage likewise, the summary of unconfined compressive strength shows same. This indicates that the additives improves the geotechnical properties of the soil samples to a certain percentage and conversely, have a negative effect on it at a higher percentage 8% and 10% respectively.