Dual effectiveness of lithium salt in controlling both delayed ettringite formation and ASR in concretes

Journal Article · Fri Jun 15 04:00:00 EDT 2007 · Cement and Concrete Research

DOI:https://doi.org/10.1016/j.cemconres.2007.01.014· OSTI ID:20995392

Ekolu, S O ^[1]; Thomas, M D.A. ^[1]; Hooton, R D ^[1]

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1. Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, ON, M5S 1A4 (Canada)

The influence of lithium nitrate on expansions due to delayed ettringite formation (DEF) and alkali-silica reaction (ASR) has been investigated. Effects of the lithium salt were examined in heat-cured mortars and concretes containing one or both damage mechanisms. The mortars and concretes made using reactive and/or non-reactive aggregates were subjected to heat treatment consisting of a hydration delay period of 4 h at 23 deg. C followed by steam-curing at 95 deg. C and then stored in limewater. Results showed that the lithium salt admixture was able to reduce the occurrence of deleterious expansion due to delayed ettringite formation in addition to controlling alkali-silica reaction in cementitious systems containing one or both mechanisms. In concretes made using non-reactive limestone aggregates, incorporation of lithium nitrate in a proportion of 0.74 M ratio of Li to (Na + K) was found to control delayed ettringite formation during the one-year period of this study. By analyzing the leaching properties of lithium and other alkalis from mortars during storage, it was found that a substantial amount of lithium was retained in the cementitious system in a slightly soluble form, and is expected to be responsible for reducing DEF.

• OSTI ID: 20995392
• Journal Information: Cement and Concrete Research, Journal Name: Cement and Concrete Research Journal Issue: 6 Vol. 37; ISSN 0008-8846; ISSN CCNRAI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CONCRETES
CURING
DAMAGE
HEAT TREATMENTS
HYDRATION
LEACHING
LIMESTONE
LITHIUM NITRATES
MORTARS
POTASSIUM NITRATES
SILICA
SODIUM NITRATES
STEAM
TEMPERATURE RANGE 0273-0400 K