Assessment of Performance Properties of Stabilized Lateritic Soil for Road Construction in Ekiti State

Soil Stabilization usually enhances performance properties of soil. This can foster waste to wealth policy in country like Nigeria. The aim of this study is to assess performance properties of a stabilized lateritic soil with a view to obtain a cheap and more effective additive. Soil samples were collected from the study area and subjected to Compaction and California Bearing Ratio (CBR) laboratory tests with the addition of 2%, 4%, 6%, 8% and 10% Rice Husk Ash (RHA) and Egg Shell Ash (ESA). Results showed that MDD, OMC and CBR values varied from 1575Kg/m3 to 1930Kg/m3, 7.55% to 18.50% and 20% to 131% respectively for sample A. And 1566Kg/m3 to 1896Kg/m3, 7.53% to 16.90% and 16% to 98% respectively for sample B. The MDD values decrease with increase in the additives contents due to the replacement of soil by the additives in the mixture, coating of the soil by additives which resulted in large particles with larger voids and density; and addition of the additives which decreased the quality of free silt, clay fraction and coarse materials with large surface areas formed. OMC values also increase as the additives increase, though, that of RHA increases more than that of ESA. This is due to the increase in additives which resulted to increase in the amount of water required in the system to adequately lubricate all the particles in the mixture equally increase. Generally, CBR values also increase with increase in the additives contents. This could be attributed to gradual formation of cementitious compound between the additives and Calcium Hydroxide (Ca(OH)2) present in the soil, thus increase in coarse particles of the soil through cementation.