Title:
Time-Dependent Diffusion Modeling of Concrete with Cement Containing Limestone and Inorganic Process Additions
Author(s):
Mustapha A. Ibrahim and Mohsen A. Issa
Publication:
Materials Journal
Volume:
113
Issue:
6
Appears on pages(s):
837-848
Keywords:
chloride diffusion; inorganic process additions; insoluble residue; modeling; supplementary cementitious materials; surface chloride concentration
DOI:
10.14359/51689243
Date:
11/1/2016
Abstract:
Replacing cement with limestone and inorganic process additions (IPAs) and increasing the insoluble residue (IR) can aid in reducing the CO2 emission. This paper investigates the effect of adding IPA and increasing IR on the diffusivity characteristics of concrete. Also, the effect of replacing cement with supplementary cementitious materials while batching them with two sand types was demonstrated. To show the effect of these materials, the chloride diffusion test was conducted on 26 concrete mixtures with different proportions that were salt ponded for 90, 180, and 360 days. The IPA addition and increase in IR did not show any notable influence on concrete diffusivity. On the basis of the experimental results, a diffusion model with time-dependent surface chloride and diffusion coefficient was developed. The proposed model was compared with existing service-life prediction software and models, and showed promising results, while the current equations adopted by the software were very conservative.