Sacrificial Point Anodes for Cathodic Prevention of Reinforcing Steel in Concrete Repairs: Part 1—Polarization Behavior Available to Purchase

The polarization behavior of commercial galvanic point anodes for corrosion protection of reinforcing steel in patch repairs applications was investigated. Concrete specimens were used to analyze the polarization history of the embedded sacrificial anodes under galvanostatic load and in yard slabs as a function of anode service aging. The results were used to develop a characteristic time-dependent potential-current function (PF) of each anode type. Typically, the performance function showed relatively little anodic polarization from an open-circuit potential at low current levels, followed by an abrupt increase in potential as the current approached an apparent limiting value. Aging of the anodes was manifested by significantly steeper PF as time and total charge delivered increased. Modest to poor steel polarization levels were achieved when coupled with point anodes in yard slabs tests. There was marked performance function variability among replicate units of one anode type. The results are used for cathodic prevention performance modeling in a companion (Part 2) paper.