Application of Very Low Frequency Electromagnetic (VLF-EM) and 2D Electrical Resistivity Methods for Pre-Foundation Studies at Nuhu Bamalli Polytechnic, Zaria
Main Article Content
Abstract
Information from the department of physical planning of Nuhu Bamalli Polytechnic Zaria reveal that the study area is a propose site for future development of physical infrastructure of the school and inspection of existing buildings near study area shows formations of cracks. This may compromise the building's quality, potentially leading to its collapse, which could result in the loss of lives and property. An integrated geophysical investigation involving the 2D resistivity imaging and very low frequency electromagnetic (VLF –EM) methods at propose site for future development of physical infrastructure in study area was investigated to obtained the suitability of the subsurface material for the design and foundation of buildings. The data were collected using ABEM Terrameter SAS 4000 with electrode selector along 35 profiles running orthogonally employing dipole-dipole array with an equally spacing electrode of 5m. The apparent resistivity obtained from field was processed and interpreted using RES2DINV software to produced two-dimensional image of the study area. The result of the inverted 2D resistivity imaging revealed that the site is predominantly dominated by low resistivity values at near surface with sparsely high resistivity values at some places. The low resistivity values that ranges from 37 Ωm to 139 Ωm, typifies high clay content materials which has a negative impact on any structure that will be erected on the site. The interpretation of 2D resistivity imaging shows that the 4 profiles indicated the presence of geologic structure such as fracture, fault or depression in the bed rocks. These profiles were further investigation by employing VLF-EM method in order to compliment the result obtained from the 2D resistivity model. The VLF EM data was collected along the 4 profiles selected for further investigation with an inter-station distance of 5 m along each profile and a total spread length of 200 m.
Downloads
Article Details
References
Ademila, O. (2021). Combined geophysical and geotechnical investigation of pavement failure for sustainable construction of Owo-Ikare highway, Southwestern Nigeria. NRIAG Journal of Astronomy and Geophysics, 10(1), 183-201.
Ademila, O. (2022). Pre-foundation geophysical investigation of a site for structural development in Oka, Nigeria. NRIAG Journal of Astronomy and Geophysics, 11(1), 81–112. https://doi.org/10.1080/20909977.2021.1953297
Agada, L. E. and Sonloye, S. A. (2024). Geophysical Investigation of Bulding Distress in Gashua, Nigeria. Nigerian Journal of physics (NJP), Published by Nigerian institute of physics. Vol 33(S) pp 180
Akingboye, A. S., & Ogunyele, A. C. (2019). Insight into seismic refraction and electrical resistivity tomography techniques in subsurface investigations. Rudarsko-geološko-naftni Zbornik, 34(1)
Alao, J. O., Lawal, K. M., Dewu, B. B. M., & Raimi, J. (2024). The effectiveness of very low-frequency electromagnetics (VLF-EM) method in detecting buried targets at a controlled site. Discover Applied Sciences, 6(1), 29.
Atilade, A. O., Coker, J. O. and Adebisi, N. O. (2024). Integrated Geophysical and Geotechnical Methods for Pre-Foundation Investigations at Lagos State University of Science and Technology, Ikorodu, Southwestern Nigeria. Nigerian journal of physics (NJP), Published by Nigerian institute of physics. Vol 33(S) pp 141
Fatoba, J. O., Fajana, A.O., Folorunso, A. F., and Ariyo S. O. (2017). Seismic Refraction and Electrical Resistivity Investigation of Building Failure: A Case Study. FUOYE Journal of Engineering and Technology, Volume 2, Issue 1. ISSN: 2579-0625 (Online), 2579-0617.
Fraser, D.C (1969).Contouring of VLF-EM data Geophysics, 34: 958–967 Grant, F. S and West, G.F. Interpretation Theory in Applied Geophysics, (McGraw Hill Books Co N, 1965).
Hellman, K., Ronczka, M., Günther, T., Wennermark, M., Rücker, C., & Dahlin, T. (2017). Structurally coupled inversion of ERT and refraction seismic data combined with cluster-based model integration. Journal of Applied Geophysics, 143, 169-181.
Ibrahim, K. O., Ahmed, A., Oke, S. A., Yusuf, M. A., Olawumi, H. B., & Oniyangi, A. K. (2024). An approach for assessment of building failures in a part of Ilorin, Nigeria. All Earth, 36(1), 1-13.
Karous, M., Hjelt (1983). Linear filtering of VLF dip-angle measurements. Geophysical prospecting 31, 782-794.
Kolawole, T., Ajani, O. O., Adeniji, A. A., Aweda, F. O., & Adagunodo, T. A. (2024). Geophysical Investigation of the Subsurface Structural Competency Around College of Computing and Communication Studies, Bowen University, Iwo, Osun State, South West Nigeria. International Journal of Research and Innovation in Applied Science, 9(3), 57-68.
Molua, C. O. and Ataman, J. O. (2023). Mapping Dumpsite Plumes in Umunede Aquifers Using Very Low Frequency (VLF) Electromagnetic Field Techniques Nigerian journal of physics (NJP), Published by Nigerian institute of physics. Vol 32(2) pp 115
Olayinka, L.A., Aremu, B.G.,Ahmed , A.L and Lawal , K.M (2019) Application of Electromagnetic and Electrical Resistivity method for foundation studies at Ahmadu Bello University Phase II, Zaria. Bayero University journal of pure and Applied sciences, 12(1): 57-62
Olubusola, I. S., Oyelami, C. A., Olumide, A. J., Adesola, B. M., Adebo Babatunde, A., & Idowu, R. (2022). Application Of Statistical Analysis On The Dynamics Of Foundation Studies Using Geophysical Parameters In A Typical Sedimentary Environment, South South Nigeria. Earth Sciences Malaysia (ESMY), 6(1), 66-75.