Use of the Accelerated Mortar Bar Test for Evaluating the Efficacy of Mineral Admixtures for Controlling Expansion due to Alkali-Silica Reaction

In order to study the effects of slate powder on mineral admixtures in suppressing ASR of slate aggregate, refer to the following methods: accelerated mortar bar test in “Standard for Constructional Quality Acceptance of Railway Concrete Engineering” TB10424-2010 and “Durability Design of Railway Concrete Structures” TB10005-2010, as well as an improved steam curing method. The text has studied the expansion of the specimens that are made from slate aggregate with different powder contents and specimens using slate powder as admixtures. The results show : When powder content in aggregate is less than 20%, it dose not have adverse effects; ASR of high-activity slate aggregate can be suppressed by using 30% fly ash and 5% silica fume as mineral admixtures; when the mineral admixtures are effective, a certain amount of powder mixed with admixtures can contribute to suppression; the main mechanism that slate powder can suppress ASR is that alkali in concrete can be consumed and physically diluted by slate powder.

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How does fly ash mitigate alkali–silica reaction (ASR) in accelerated mortar bar test (ASTM C1567)?

Cement and Concrete Composites ◽

10.1016/j.cemconcomp.2012.11.004 ◽

2013 ◽

Vol 37 ◽

pp. 143-153 ◽

Cited By ~ 71

Author(s):

Seyed M.H. Shafaatian ◽

Alireza Akhavan ◽

Hamed Maraghechi ◽

Farshad Rajabipour

Keyword(s):

Fly Ash ◽

Alkali Silica Reaction ◽

Accelerated Mortar Bar Test ◽

Bar Test ◽

Mortar Bar

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Effect of the Composite of Fly Ash and Slag on Alkali-Silica Reaction

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.936.1428 ◽

2014 ◽

Vol 936 ◽

pp. 1428-1432

Author(s):

Tong Chao Liu ◽

Bo Xiao ◽

Gu Hua Li ◽

Nian Hong Luo ◽

Long Sheng Zhang

Keyword(s):

Fly Ash ◽

Inhibitory Effect ◽

Alkali Silica Reaction ◽

Alkali Aggregate Reaction ◽

Accelerated Mortar Bar Test ◽

Bar Test ◽

Mortar Bar ◽

Better Than

The study used the method of accelerated mortar bar test to study alkali aggregate reaction (ASR) with sandstone aggregate. Both fly ash and slag can inhibit the expansion of mortar bar. Results show that 50% slag can inhibit ASR reluctantly, but 10% fly ash and 20% slag can inhibit ASR very well, and the inhibitory effect of fly ash is far better than slag. Because of the high content of CaO in slag, it has inhibit and promote aspects, when the ASR is fierce, slag can inhibit ASR, otherwise slag can promote ASR.

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Study on Experiments of Matekaolin in Relation to Alkali-Silica Reaction

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.629-630.528 ◽

2014 ◽

Vol 629-630 ◽

pp. 528-533

Author(s):

Hong Yi Zhou ◽

Fu Hai Li ◽

Si Yin Chen ◽

Xiao Gang Zhao ◽

Gu Hua Li

Keyword(s):

Fly Ash ◽

Significant Influence ◽

Sem Analysis ◽

Alkali Silica Reaction ◽

Result Show ◽

Glass Aggregate ◽

Accelerated Mortar Bar Test ◽

Bar Test ◽

Mortar Bar

The influence of the content of matekaolin powder and fly ash in cement on controlling ASR was evaluated using Accelerated Mortar Bar Test (AMBT). Replacing cement with matekaolin powder to the extent of 5%,10%,15%,20%,25%,and with fly ash to the extent of 10%,20%,30%,35%,40%, 45% respectively. The result show that matekaolin powder and fly ash both can control Alkali-aggregate activity but to different degrees. Small amount of metakaolin powder exerts significant influence, whereas only when the proportion of fly ash is up to 35%, can it control ASR effectively. The effect and mechanism of the control of the extension of glass aggregate activity was studied by means of SEM analysis.

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