A geophysical and geotechnical pre-foundation study on the proposed ICT center of the Olusegun Agagu University of Science and Technology (OAUSTECH), Okitipupa, was carried out to determine the suitability and competency of the subsurface soil and evaluate its engineering implications for infrastructural development. The Dipole-Dipole array, with a spacing of 5 meters, was used to investigate the subsurface lithology and its suitability for construction application in relation to the depth, thickness, and resistivity of subsurface materials. Three (3) traverses, 110 meters each, were employed. Four (4) soil samples randomly taken at depths of 0.5 meters were used to carry out geotechnical laboratory tests. The first layer resistivity ranges from 153 ohm-m – 1005 ohm-m with maximum thickness of approximately 2 meters, the second layers resistivity value ranges between 1162 ohm-m to 84965 ohm-m with corresponding thickness of 10 meters – 15 meters, and the third layer has resistivity values above 221486 ohm-m. Geotechnical analysis carried out on the soil samples obtained are Natural Moisture Content (NMC) with values between 14.1% to 14.3%, Grain Size Analysis with > 50% finer passing, Atterberg Limit Test with plastic limit ranging from 19.4% to 19.9%, Consolidation test ranging from 0.0131 – 0.0136m²/yr, Unconfined Compression (UC) Test revealing approximately 182.5Kla, Permeability test ranging from 1.33×10-5 cm/s to1.85×10-5 cm/s, and Specific Gravity (SG) of 2.648 - 2.654. Three geological layers were inferred namely; clayey sand, sandy clay and sand. From the geophysics and geotechnical it can be inferred that the study area is competent. But Excavation of soil to a depth of about 2 meter at which the soil is adequately competent (consolidated) is recommended.
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