Dependency of Soil Resistivity on Soil Factors for Optimal Grounding System Performance: A Case Study of Six Sites at Funaab, Nigeria

Abstract:

An efficient grounding system design for safe fault current discharge requires the knowledge of soil resistivity. This study analysed the dependency of soil resistivity (ρ_s) on some soil factors such as soil texture (ST), moisture content (MC), temperature (T) and depth (D) for optimal grounding system operation. Two seasonal measurements of ρ_s were conducted during rainy season (July 2023) and dry season (January 2024) at six different sites in Federal University of Agriculture, Abeokuta (FUNAAB), Ogun State, Nigeria as a case study. Using Herojat Rhomega-smart resistivity meter, the ρ_s at the sites was measured via Wenner method. The ST and MC were determined via laboratory analysis of five 5 kg samples of soil from each site at the D values generated by the meter while T was measured using a thermometer. The ρ_s dependency on MC, T and D at each site was modelled using multiple linear regression (MLR). Coefficient of determination (R²) was used to determine MC, T and D contributions to ρ_s. The obtained results revealed that the measured ρ_s at the six sites over the study period was a function of ST, MC, T and D. The developed MLR models for the sites for both rainy and dry seasons showed that MC, T and D collectively influenced the ρ_s value better than the individual factors owing to higher value of multiple R² observed. The outcomes of this study could be adopted as good reference points for further soil resistivity analysis and grounding system installation for FUNAAB.

• Periodical: Applied Mechanics and Materials (Volume 932)
• Pages: 163-173
• DOI: https://doi.org/10.4028/p-k9Auzt
• Online since: February 2026
• Authors: Oluwaseun Ibrahim Adebisi*, Mofolorunsho Adegoriola Akinyemi, Kamoli Akinwale Amusa, Funmilayo Modupe Alayaki, Tolulope Christiana Erinosho, Peter Olayemi Olaogun, Maurice Antigha Ita
• Keywords: Coefficient of Determination, Fault Current, Grounding System, Multiple Linear Regression, Soil Resistivity, Wenner Method

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