2008 Annual Meeting
(702c) Dynamics of Solvated Chloride Inhibition by Nanoparticle Treated Concrete
Authors
In this work, molecular simulations are used to investigate solvated chloride anion (Cl-) diffusion through nanoporous calcium silicate hydrate (the main binder phase in Portland cement), when alumina (Al2O3) and silica (SiO2) nanoparticles are present inside the pore. First, equilibrium properties of the chloride-water system are explored as a gradual approach to obtaining a hydrated ion model using Density Functional Theory. Cl- ion mobility in nanoparticle-reinforced, nanoporous, tricalcium silicate is investigated through calculations of diffusion coefficients for different electric field strengths using Molecular Mechanics and Molecular Dynamics simulations. Different nanoparticle sizes are tested for effective Cl- blocking at different temperatures, pH, and Cl- ion concentrations, and the results are compared to the those obtained using a stochastic mathematical model and with experimental observations.
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