Simulation Studies of Methods to Delay Corrosion and Increase Service Life for Cracked Concrete Exposed to Chlorides

Published

February 18, 2015

Author(s)

Scott Z. Jones, Nicos Martys, Yang Lu, Dale P. Bentz

Abstract

The ingress of chlorides in reinforced concrete leads to the onset of rebar corrosion and eventually compromises a structure’s integrity. To extend its service life and improve safety, it is crucial to develop sound repair and rehabilitation strategies for our nation’s infrastructure. In this paper, results are presented for numerical simulations to study the effectiveness of fillers for repair of cracks in concrete, so as to delay the onset of corrosion in rebars. Concretes without cracks and with either a 50 µm or 500 µm wide crack located directly above the rebar are simulated, with the addition of silica fume, a corrosion inhibitor, or epoxy-coated reinforcement being considered as additional scenarios. The effectiveness of the crack filler depends not only on its inherent diffusivity with respect to chloride ions, but also on its ability to penetrate and fill the damaged zone or interface between the open crack region and the bulk concrete. Additional simulations indicate that simply using continuum models instead of models that include details of the rebar placement can lead to underestimating the chloride concentration and overestimating the service life. Experiments are needed to study the ingress of chlorides in damaged (interfacial) regions adjacent to the crack or at the rebar surface, as the local transport properties of these regions can significantly influence service life predictions.

Citation

Cement and Concrete Composites

Volume

58

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.cemconcomp.2014.12.014

Keywords

Chloride ingress, corrosion, crack filler, reinforced concrete, service life, transverse cracking

Citation

Jones, S. , Martys, N. , Lu, Y. and Bentz, D. (2015), Simulation Studies of Methods to Delay Corrosion and Increase Service Life for Cracked Concrete Exposed to Chlorides, Cement and Concrete Composites, [online], https://doi.org/10.1016/j.cemconcomp.2014.12.014 (Accessed January 2, 2025)