Abstract
Corrosion of reinforcing steel bars is considered the major cause of premature deterioration of reinforced concrete structures, costing owners and operators high repair bills and asset’s downtime. The Arabian Gulf’s coast is known for elevated temperatures, high humidity levels and exceptionally high chlorides in sea and land. This severe exposure dramatically reduces the corrosion initiation time and increases rebar corrosion rate. Rebar corrosion is understood to be the limiting factor for the service life of reinforced concrete structures. Therefore, Concrete Society Guide 163 [1] and other technical guidelines have recommended including an additional durability enhancement technique to help reinforced concrete assets achieve their desired service life, in excess of 30 years.
Amine carboxylate corrosion inhibiting admixture has been widely accepted globally and regionally as an effective yet economical additional durability enhancement technique. This paper will present a literature review of the latest industry standards, test methods and acceptance criteria of corrosion inhibiting admixture. The paper will also explain how lab and field result outputs were used as inputs to a service life prediction model. A simulation of service life will be presented highlighting the inputs in a typical project located near the coast in a marine exposure condition, with a specific triple blend concrete mix with various concrete covers, explaining the impact of amine carboxylate-based inhibitor on service life when added to the same mix, in each cover scenario.
