Effect of Measuring Profile and Metallic Structure on Soil Resistivity

Abstract

-Soil resistivity measurements are considered very important task for grounding system design and analysis. The metallic structures in vicinity of grounding system have significantly effect on the performance of grounding system. Ideally, soil resistivity measurements should be made in the absence of buried metallic conductors or structures. Soil resistivity measurements may have to be made in the presence of the grounding system, if the performance of an existing grounding system is necessary to review or evaluate. Soil resistivity measurements made with the Wenner are carried out with and without a nearby grounding grid, in Taif (KSA) soil. Comparisons are made between the results, with and without the grounding grid, to show the effect due to the presence of the grid. The influence of different metallic structures and modified measurement profiles which reduce the influence of metallic structures will be discussed. A mathematical model for computing the soil resistivity in case of multilayer soil will be investigated. A new technique is proposed to calculate the grounding resistance of multilayer soil by a numerical method as current simulation method.