Applied Modeling for Corrosion Protection Design for Marine Bridge Substructures

摘要

Quantitative computational models have been developed to assist in predicting thecourse of corrosion-induced deterioration and the effect of corrosion protection models in reinforced concrete marine substructures. These models use the concept of a corrosion initation stage (buildup of chloride ions until reaching a steel corrosion initiation threshold level) followed by a corrosion propagation stage (active corrosion leading to cracking and spalling of the concrete cover). Predictive models were applied to assess the reduction of corrosion rate by submerged and surface sacrificial anodes in marine piles. It was concluded that surface anodes located above water reduced corrosion significantly when the anode extended up to the top of the active steel zone. This predictive model was confirmed by parallel laboratory experiments with partially submerged piles and sacrificial anodes. Additional calculations applied the model to find the extent of cathodic protection feasible for partially submerged bridge footers with only submerged anodes.