Title: Statistical Distributions for Chloride Thresholds of Reinforcing Bars

Author(s): John S. Lawler, Jonah C. Kurth, Stephen M. Garrett, and Paul D. Krauss

Publication: Materials Journal

Volume: 118

Issue: 2

Appears on pages(s): 13-20

Keywords: carbon steel reinforcing bars; chloride threshold; corrosion; critical chloride content; durability; epoxy-coated reinforcing bars (ECR); probabilistic; service life; supplementary cementitious materials

DOI: 10.14359/51730411

Date: 3/1/2021

Abstract:
Reliability-based durability design of reinforced concrete structures requires a probabilistic service life modeling approach. Probabilistic service life modeling of chloride-induced corrosion should consider the statistical distributions of key parameters that influence corrosion initiation and subsequent damage. For typical reinforced concrete structures (such as bridge decks), these are chloride exposure, chloride penetration resistance of the concrete, chloride-induced corrosion threshold, depth of concrete cover, and corrosion propagation time. Assessing the impact of the use of corrosion-resistant reinforcement, such as epoxy-coated reinforcing bars (ECR), is typically performed through a selection of the chloride threshold and/or propagation time. This paper provides recommendations for statistical distributions for the chloride threshold to be used in service life modeling for structures containing carbon steel and ECR based on both experimental work reported in the literature and field investigations of existing structures conducted by the authors.