Evaluation of Physical and Geotechnical Characteristics of Residual Profile with Depth of Three Common Basement Complexes in Niger State

Abstract

Disturbed soil samples were collected from three different trial pit at depths of 0.5m interval, to bedrock or 5.0m. at three different basement complexes of (Granite, Schist and Gneiss) physical and geotechnical properties test were carried out on the disturbed samples, test carried out includes index properties, compaction and California Bearing Ratio (CBR), the compaction and California Bearing Ratio (CBR) test of all the soil samples were prepared using British Standard Heavy (BSH) .Evaluation of the variation of physical and geotechnical properties of the weathered basement profiles with depth were made. The result shows that soil sample of Granite and Schist has intermediate plasticity, while that of Gneiss has a low plasticity. The compaction properties of Granite, Schist and Gneiss has maximum dry density (MDD) of 1.9701kg/cm3, 2.430kg/cm3 and 2.450kg/cm3 respectively and the Optimum Moisture Content (OMC) of 15.40%, 18.00% and 9.80% accordingly. While that of the California Bearing Ratio (CBR) for both Granite, Schist and Gneiss has the maximum values of 40.42%, 25.85% and 21.60% respectively.