Title: Accelerated Chloride Threshold Testing—Part II: Corrosion-Resistant Reinforcement

Author(s): David Trejo and Radhakrishna G. Pillai

Publication: Materials Journal

Volume: 101

Issue: 1

Appears on pages(s): 57-64

Keywords: acceleration; corrosion; gradient; steel

DOI: 10.14359/12988

Date: 1/1/2004

Abstract:
Test methods to evaluate the corrosion performance of reinforcing steel have been typically developed to evaluate the corrosion rate of conventional plain carbon steel in cementitious materials. Although the corrosion rate is a necessary parameter for predicting the service life of reinforced concrete structures, these data alone are not sufficient to compare corrosion performance or to predict service life. Steel reinforcement is now being specifically produced to resist corrosion initiation and this resistance is mainly obtained by increasing the critical chloride threshold levels of the steels. A newly developed test method, the accelerated chloride threshold (ACT) test, was developed and used to evaluate the corrosion performance of three corrosion-resistant reinforcing bars embedded in mortar. Results from this test indicate critical chloride thresholds for microcomposite, 304 stainless steel, and 316LN stainless steel reinforcement is 4.6, 5.0, and 10.8 kg/m3 (7.7, 8.5, and 18.1 lb/yd3) and based on the mortar unit weight.