THE GEOTECHNICAL INDEX PROPERTIES OF SOIL IN WARRI, DELTA STATE, NIGERIA

The study of geotechnical index properties of soils in Warri, Delta state was carried out to determine the index properties of soil. The laboratory test carried out included, moisture content, grain size analysis, Atterberg limits and compaction test. As determined, recorded value ranging from 8.1 – 26.9% (moisture content), 22.0 – 38% (liquid limit), 19.5 -22.4% (plastic limit), 2.1 – 17.9% (plasticity index). While the coefficient of uniformity (CU) of the grain size is 4.2 which is less than 6 of the British Standard (BS: 1377). These results indicate that the soil is poorly graded, well drained, it is of intermediate plasticity, medium swelling potential. The results of particle grain size distribution test show that the soil sample is mainly sand that is having an average value of coarse send fraction as 36.6% medium sand fraction as 37.3% and fine sand fraction as 13.6%. This means that they will tend to increase in compressibility and decrease in shear strength. Also, as a result of their poorly graded nature, they will have negative effects such as high effective porosity, large mean pore size, how density and high permeability. The compaction results show that the maximum dry density (MDD) and the optimum moisture content (OMC) of location 1m – 6.5m range for