Geophysical and Geotechnical Investigations for Subsoil Competence at a Proposed Hostel Site at Oba Nla, Akure Southwestern Nigeria
by Festus Olusola Eebo * 
, Abidakun Bayode Samuel , Gbenga Moses Olayanju
Department of Applied Geophysics, Federal University of Technology, Akure, Nigeria
* Author to whom correspondence should be addressed.
Journal of Engineering Research and Sciences, Volume 1, Issue 2, Page # 41-49, 2022; DOI: 10.55708/js0102005
Keywords: Electromagnetic, Geotechnical tests, Magnetic anomaly, Competence, Engineering structure
Received: 30 December 2021, Revised: 19 February 2022, Accepted: 27 February 2022, Published Online: 14 March 2022
AMA Style
Eebo FO, Samuel AB, Olayanju GM. Geophysical and geotechnical investigations for subsoil competence at a proposed hostel site at Oba Nla, Akure Southwestern Nigeria. Journal of Engineering Research and Sciences. 2022;1(2):41-49. doi:10.55708/js0102005
Chicago/Turabian Style
Eebo, Festus Olusola, Abidakun Bayode Samuel, and Gbenga Moses Olayanju. “Geophysical and Geotechnical Investigations for Subsoil Competence at a Proposed Hostel Site at Oba Nla, Akure Southwestern Nigeria.” Journal of Engineering Research and Sciences 1, no. 2 (2022): 41–49. https://doi.org/10.55708/js0102005.
IEEE Style
F. O. Eebo, A. B. Samuel, and G. M. Olayanju, “Geophysical and geotechnical investigations for subsoil competence at a proposed hostel site at Oba Nla, Akure Southwestern Nigeria,” Journal of Engineering Research and Sciences, vol. 1, no. 2, pp. 41–49, 2022.
A foundation study was carried out at a proposed Hostel site for the student of Federal University of Technology Akure, Nigeria with the aim of evaluating the competence of the overburden as foundation materials. Geophysical survey involving Electromagnetic method and magnetic method were conducted in conjunction with geotechnical tests in the study area. Electromagnetics and Magnetics data were acquired along the five traverses established across the study area with 20 m inter-traverse spacing and 5 m inter-station spacing. The geophysical results were interpreted qualitatively and quantitatively, and the results were presented as profiles and geomagnetic sections. From the results of the Very Low Electromagnetic survey conducted, several conductive zones possibly characterized by clayey materials were found to make up the overburden materials in the area. Characteristic magnetic anomalies in the area also revealed series of features at shallow depths identified to be fractures / fault at shallow depths with depth to bedrock varying between 2 m and 7 m. The presence of geologic features such as fracture and conductive clayey materials are likely going to pose a serious threat to engineering structure in the area. Geotechnical tests were carried out on soil samples from the study area and different geotechnical parameters analyzed include the natural moisture content, Atterberg Limits, unconfined compressive strength and shear strength. The specific gravity of the soils is within the range of 2.722 – 2.73 g/cm3, revealing materials of low water absorption capacity. However, the soils are highly plastic with the plastic limit ranging from 20.4 – 24.4% and a plasticity index range of 23.75 – 35.90%. In addition, the soils have shear strength within the range of 75 to 102 kPa and unconfined strength ranging from 150 to 203 kPa revealing stiff soils that are not suitable for shallow foundations. It was observed that the form of foundation suitable for infrastructural development in the study area is a properly designed deep foundation that can transfer load at grater depths.
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