ABSTRACT

A geotechnical evaluation of some soils in Choba, Port Harcourt, South-South, Nigeria has been carried out. This was done to determine the suitability of the soils for use as subgrade/filling, sub-base and base course materials for road construction. The samples were collected from ten different areas, at surface and sub-surface levels. The areas are along Rumuokoro – Choba within the East – West Road. The soil samples were subjected to laboratory investigations in conformity with the American Association of State Highway and Transportation (AASHTO) specifications. Results of the geotechnical tests indicate that the proportion passing the AASHTO sieve N0. 10 - 60 range from Cc: 1.59% to D60: 0.450% whereas plasticity index ranges from 4.4.0 to 26.1 respectively. The compaction test result revealed an optimum Moisture Content (O.M.C) value of 18.70% and a maximum Dry Density (M.D.D) value is 1983kg/m3. The plastic limit values ranges from 25.8% to 65.0%. Soils at Choba and its environs are thus considered suitable for use as sub-grade/filling materials, while the soil at some sites are unsuitable for use as subgrade/filling and sub-base material. This is probably why the road at these areas failed after construction.