Functional relationship between cathodic protection current/potential and duration of system deployment in desert conditions

摘要

This paper analyzes the attenuation of cathodic protection (CP) current/potential in pre-stressed concrete cylinder pipes while using galvanic anodes during system employment. The focus in this paper is on the functional relationship between CP current/potential and the duration of system employment in desert conditions. The purpose of this paper is to reach an approximate formula for the functional relationship current/potential following a deployment of a CP system. Consequently, costly field measurements of said PCCP current/potential can be avoided, thus rendering a more efficient operation of the CP system. These measurements have been taken in desert conditions in sections with very high and low soil resistivity during 22 months. Field measurements confirm that there is a substantial reduction of CP current magnitude following initial CP system deployment. Field data confirm the existence of the correlation between CP current and the time of system exploitation, until the point where full system polarization occurs. For both values of soil resistivity, based on measured current values over time, the paper presents a regression model that is a determined two-term exponential equation.