Simplified formulas for the ground resistance of the human body for two-stratus soil

The aim of this work is to propose new simplified formulas for the calculation of the ground resistance of plate electrodes placed on two-stratus soil. The main utility of this study is the determination of the resistance to ground of human body (R_EB), since feet can be assimilated to plates, placed on the soil, to evaluate the step voltage and the touch voltage, to which the subject can be submitted in the case of a fault in HV systems. The evaluation of R_EB, depending on the resistivities of the soils and on the thickness of the insulating layer, is useful to establish the safety level of the electrical system. The research have been carried out with numerical methods using FEM models; the results have been compared with pre-existing analytical and semiempirical equations and with experimental tests on civil materials in laboratory on a scale model.