Two-Scale Modeling of Transport Properties of Cement Paste: Formation Factor, Electrical Conductivity and Chloride Diffusivity

Abstract

Predicting transport properties of cement-based materials directly from the microstructure is very challenging, due to the problems of bridging length scales and the difficulties of realistically representing the microstructure. Based on a two-scale representation of the microstructure, a scheme is proposed in this paper to model the transport properties of cement paste through two-scale random walk simulation. A random walk algorithm is firstly applied at the sub-micro-scale to determine the diffusion tortuosity of the outer C-S-H layer. This is then up-scaled to the micro-scale to compute the diffusion tortuosity of cement paste. Based on physical laws, the diffusion tortuosity is transformed into the formation factor, and further into the electrical conductivity and the chloride diffusion coefficient of cement paste, and subsequently validated. It is proven that a more realistic representation of the microstructure makes it possible to derive transport properties of cement paste, directly and accurately, from the microstructure.

Department(s)

Civil, Architectural and Environmental Engineering

Keywords and Phrases

Diffusion; Electric Conductivity; Electron Transport Properties; Microstructure; Random Processes; Salinity Measurement; Transport Properties; Cement Based Material; Cement Paste; Chloride Diffusion Coefficient; Electrical Conductivity; Multi-Scale; Random Walk; Random Walk Algorithms; Random Walk Simulation; Cements

International Standard Serial Number (ISSN)

0927-0256

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2015 Elsevier, All rights reserved.

Publication Date

01 Dec 2015

Link to Full Text

Share

 
COinS