TY - JOUR
T1 - Electrically driven chloride ion transport in blended binder concretes
T2 - Insights from experiments and numerical simulations
AU - Aguayo, Matthew
AU - Yang, Pu
AU - Vance, Kirk
AU - Sant, Gaurav
AU - Neithalath, Narayanan
N1 - Funding Information:
The authors gratefully acknowledge the National Science Foundation for the financial support for this research (CMMI: 1068985 ). The materials were provided by the U.S. Concrete, OMYA A.G., Headwaters Resources, and Burgess Pigments and are acknowledged. This research was conducted in the Laboratory for the Science of Sustainable Infrastructural Materials at Arizona State University and the support that has made this laboratory possible is acknowledged. The contents of this paper reflect the views of the authors who are responsible for the facts and accuracy of the data presented herein, and do not necessarily reflect the views and policies of the funding agency, nor do the contents constitute a standard, specification, or a regulation.
PY - 2014/8/19
Y1 - 2014/8/19
N2 - Chloride ion transport driven by electrical potential gradients is discussed in concretes wherein OPC is partially replaced by limestone or a combination of limestone and fly ash/metakaolin at replacement levels of 20% or 35% (volume-basis). The ternary formulations demonstrate non-steady state Cl- migration (NSSM) coefficients that are comparable to or lower than those of the control OPC concretes, with metakaolin blends showing markedly better performance. A pore structure factor extracted through electrical conductivity measurements before the NSSM test is correlated with Cl- penetration depths after the migration test. The transport of all ionic species (Cl-, OH-, Na+, K+) is modeled using an explicit finite element framework via the coupled Poisson-Nernst-Planck (PNP) equation with suitable consideration of: (a) concentration (depth)-dependent diffusion coefficients, (b) pore-structure factor, and (c) Cl- binding. With informed inputs of material properties, the simulations are able to reliably capture Cl- penetration behaviors in plain and blended binder formulations.
AB - Chloride ion transport driven by electrical potential gradients is discussed in concretes wherein OPC is partially replaced by limestone or a combination of limestone and fly ash/metakaolin at replacement levels of 20% or 35% (volume-basis). The ternary formulations demonstrate non-steady state Cl- migration (NSSM) coefficients that are comparable to or lower than those of the control OPC concretes, with metakaolin blends showing markedly better performance. A pore structure factor extracted through electrical conductivity measurements before the NSSM test is correlated with Cl- penetration depths after the migration test. The transport of all ionic species (Cl-, OH-, Na+, K+) is modeled using an explicit finite element framework via the coupled Poisson-Nernst-Planck (PNP) equation with suitable consideration of: (a) concentration (depth)-dependent diffusion coefficients, (b) pore-structure factor, and (c) Cl- binding. With informed inputs of material properties, the simulations are able to reliably capture Cl- penetration behaviors in plain and blended binder formulations.
KW - Blended cements (D)
KW - CaCO3 (D)
KW - Diffusion (C)
KW - Microstructure (B)
KW - Transport properties (C)
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U2 - 10.1016/j.cemconres.2014.07.022
DO - 10.1016/j.cemconres.2014.07.022
M3 - Article
AN - SCOPUS:84906303035
SN - 0008-8846
VL - 66
SP - 1
EP - 10
JO - Cement and Concrete Research
JF - Cement and Concrete Research
ER -