FEM simulation of a grounded carbon steel pipe under impressed current cathodic protection

Cathodic protection is a well-known technique to control corrosion of buried structures, even in the presence of a grounding system. In fact, without cathodic protection, the grounded carbon steel structure is subject to galvanic corrosion due to the coupling with Cu wires or rods, being the latter more noble than carbon steel. In the present study, different scenarios have been modelled by finite element method (FEM), to study the effect of coating defects, high and low protection current densities and different soil resistivity on cathodic protection condition. The simulations highlight the paramount importance of two parameters: the definition of a minimum total protection current (pipe and grounding) to ensure a proper protection level and the soil resistivity.