Cathodic Protection Studies on Reinforced Concrete: Fid-Bau Portal

Cathodic Protection Studies on Reinforced Concrete

G. H. C. Chang / J. A. Apostolos / F. A. Myhres

This report presents field and laboratory studies relating to monitoring techniques, materials, and instrumentation used on reinforced concrete bridge decks under cathodic protection. It provides followup data on Sly Park Bridge, the first known deck to be placed under experimental cathodic protection, first reported in 1974. Effects of concrete temperature and moisture changes on potential measurements are documented and discussed. Use of an oscilloscope voltmeter, to avoid turning off the cathodic protection current is presented. Use of corrosometer probes, and isolated reinforcing bars as current and corrosion monitors is discussed. Impressed current anode data are presented. An attempt to develop a conductive concrete overlay using 100% coke as the aggregate is documented. High-silicon iron anodes were inspected after five years intermittent operation, and were found to be performing very well in a conductive layer of coke and asphaltic binder. Inspections and brief studies of mild steel, platinum coated, and copper anodes are also reported.