Influence of soil chemical characteristics on corrosion behaviour of galvanized steel

Hot-dip galvanized steel is widely used for the construction of underground structures, thanks to presence a zinc coating that able protect carbon substrate through formation corrosion products layer. Soil very complex process and hence it difficult predict resistance specific component because many factors can directly influence behavior material immerged in soil. This work focused on effect chlorides sulphates concentrations hot-dip wires buried In particular, were monitored by means electrochemical techniques, as open circuit potential, impedance spectroscopy potentiodynamic polarization. Moreover, at end exposure, samples extracted observed optical electron microscopy, examine corroded surface morphology. The analysis evidenced severe, producing great degradation coating. synergistic performed combined action these elements caused, most critical situation, protection loss external layer, putting direct contact with soil, therefore obtaining substantial reduction resistance.