Estimation of consumption of a sacrificial anode from cathode potential in a seawater environment

Sacrificial anodes are widely used for cathodic protection of steel structures in seawater environments. The anode must be replaced before being depleted, and the main objective of this study is to investigate the practical applicability of this method of estimating anode consumption. The field test facility used in the present was a steel pipe pile structure at Yamanouchi Wharf in Yokohama Port, Japan. The consumption of the anode was estimated from the resistivity of seawater and the potential of the steel pipe pile. This estimated anode consumption is the same as that obtained from the protective current generated from the anode, which is given by the voltage drop across the shunt resistance. This result demonstrates that the amount of consumption of the anode can be estimated based upon potential and resistivity survey data.