Alkali-Silica Reaction as Cause of Distress in Concrete Pavements Made from Purported Alkali-Carbonate Reaction Aggregate

In this study, concrete microbars and rock prisms made of dolomitic aggregates were cured in a 1-mol/L tetramethylammonium hydroxide (TMAH) solution at 80 °C to avoid the effect of alkali–silica reaction (ASR) on expansion. The expansion of specimens was only caused by the alkali–carbonate reaction (ACR). The reason that self-made cement was used in this work was to ensure that the Mg2+ contained in the brucite originated only from dolomite. Expansion of concrete microbars and rock prisms was measured, the expansion cracks were systematically observed by orthogonal polarizing microscopy, and the products of ACR were analyzed by scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The results showed that the dolomite crystals in the dolomitic aggregates reacted with the TMAH solution and resulted in ACR, which formed calcite and brucite and led to cracking of the specimens. The source of the expansion was the dolomite crystals of the dolomite enrichment area. Expansion cracks either extended inside the rock or into the cement phase and eventually disappeared. The alkali–carbonate reaction significantly contributed to the expansion of dolomitic aggregates cured in TMAH solution at a later curing age.

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Alkali Silica Reaction (ASR) as a root cause of distress in a concrete made from Alkali Carbonate Reaction (ACR) potentially susceptible aggregates

Cement and Concrete Research ◽

10.1016/j.cemconres.2013.04.014 ◽

2013 ◽

Vol 51 ◽

pp. 85-95 ◽

Cited By ~ 11

Author(s):

M. Beyene ◽

A. Snyder ◽

R.J. Lee ◽

M. Blaszkiewicz

Keyword(s):

Alkali Silica Reaction ◽

Root Cause ◽

Alkali Carbonate ◽

Carbonate Reaction

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Is alkali–carbonate reaction just a variant of alkali–silica reaction ACR=ASR?

Cement and Concrete Research ◽

10.1016/j.cemconres.2009.09.002 ◽

2010 ◽

Vol 40 (4) ◽

pp. 556-562 ◽

Cited By ~ 32

Author(s):

P.E. Grattan-Bellew ◽

L.D. Mitchell ◽

James Margeson ◽

Deng Min

Keyword(s):

Alkali Silica Reaction ◽

Alkali Carbonate ◽

Carbonate Reaction

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Dolomitic filler in self-compacting concrete: a review

RILEM Technical Letters ◽

10.21809/rilemtechlett.2020.118 ◽

2020 ◽

Vol 5 ◽

pp. 75-83

Author(s):

Ahmed Abdalqader ◽

Mohammed Sonebi

Keyword(s):

Key Factors ◽

Self Compacting Concrete ◽

Factors Affecting ◽

Chemical Admixtures ◽

Wide Range ◽

Alkali Carbonate ◽

Self Compatibility ◽

Hardened Properties ◽

By Products ◽

Carbonate Reaction

The utilization of fine powders as fillers in self-compacting concrete (SCC) application is widespread, particularly in Europe. The incorporation of these fillers to attain the self-compatibility properties of SCC seems to be cheaper than the use of chemical admixtures. Among the wide range of potential fillers, dolomitic powders, particularly generated as by-products from quarry’s processing, are locally available and can be used to produce SCC. Few studies have shown that dolomitic powders can be incorporated in the SCC’s mix design, resulting in acceptable fresh and hardened properties of SCC. The particle size distribution and fineness of the dolomitic powder as well as the level of addition are the key factors affecting those properties. The influence of the chemical nature of the dolomitic powder on the properties of SCC, particularly the durability (e.g. alkali-carbonate reaction), is yet to be investigated. Furthermore, more efforts are still required to investigate the use of dolomitic by-products in the production of SCC.

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