Earthing system’s design in presence of non-uniform soil

The Authors propose a practical approach for facing the problem of the design of the earthing systems in two-layer soils. The approach is based on the calculation of an equivalent resistivity of the non-uniform soil through which the designer can treat this one as it was uniform. The purpose of the Authors is to provide an innovative simple method and some easy-to-use graphs for an easy earthing systems’ design in two-layer soils.