Summary of research on the effect of LiNO{sub 3} on alkali-silica reaction in new concrete

Journal Article · Thu Apr 15 00:00:00 EDT 2010 · Cement and Concrete Research

DOI:https://doi.org/10.1016/j.cemconres.2009.08.021· OSTI ID:21344756

Feng, X ^[1]; Thomas, M D.A., ^[1]; Bremner, T W ^[1]; Folliard, K J ^[2]; Fournier, B ^[3]

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1. Department of Civil Engineering, University of New Brunswick, Fredericton, NB (Canada)
2. Concrete Durability Center, University of Texas at Austin, TX (United States)
3. Department of Geological Engineering, Laval University, Quebec, PQ (Canada)

This paper summarizes findings from a research study conducted at the University of New Brunswick in collaboration with the University of Texas at Austin, and CANMET-MTL, on the effect of LiNO{sub 3} on ASR in new concrete. The studies included expansion testing, silica dissolution measurements and microstructural examinations of cement systems containing glass and two different reactive aggregates (NB and NS). Only a small proportion of the data are presented here for the purpose of highlighting the principal findings of this investigation. Based on these findings, it is proposed that the inhibiting effect of LiNO{sub 3} against ASR in new concrete is attributed to the formation of two reaction products in the presence of lithium, these being a crystalline lithium silicate compound (Li{sub 2}SiO{sub 3}) crystal and a Li-bearing, low Ca silica gel. These two phases could serve as a diffusion barrier and protective layer to prevent the reactive silica from further attack by alkalis. It was found that the reason the two reactive aggregates selected responded differently to LiNO{sub 3} was due to the difference in their textural features. The NB aggregate contained reactive volcanic glass particles, the surface of which was immediately and equally available to sodium, potassium and lithium, and thus a Li-Si barrier was able to form quickly. The reactive phase in the NS aggregate was microcrystalline and strained quartz, which was embedded in a dense matrix of a non-reactive predominantly alumino-silicate phase and was not easily accessible to lithium.

• OSTI ID: 21344756
• Journal Information: Cement and Concrete Research, Vol. 40, Issue 4; Conference: ICAAR 13:13. international conference on alkali-aggregate reaction in concrete, Trondheim (Norway), 16-20 Jun 2008; Other Information: DOI: 10.1016/j.cemconres.2009.08.021; PII: S0008-8846(09)00227-0; Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; ISSN 0008-8846
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CEMENTS
CONCRETES
DIFFUSION BARRIERS
GLASS
LAYERS
LITHIUM
LITHIUM NITRATES
LITHIUM SILICATES
MICROSTRUCTURE
POTASSIUM
QUARTZ
SCANNING ELECTRON MICROSCOPY
SILICA
SILICA GEL
SODIUM
SURFACES
ADSORBENTS
ALKALI METAL COMPOUNDS
ALKALI METALS
BUILDING MATERIALS
ELECTRON MICROSCOPY
ELEMENTS
LITHIUM COMPOUNDS
MATERIALS
METALS
MICROSCOPY
MINERALS
NITRATES
NITROGEN COMPOUNDS
OXIDE MINERALS
OXYGEN COMPOUNDS
SILICATES
SILICON COMPOUNDS