The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review
Alkali-silica reaction (ASR) of reactive aggregates is a major durability concern of concrete. The use of fly ash as a supplementary cementing material (SCM) shows a reliable way to control ASR expansion. This paper investigates the recent findings on effects of coal fly ash as a SCM on ASR of react...
| Main Authors: | , , , , |
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| Format: | Journal Article |
| Published: |
Elsevier BV
2018
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| Online Access: | http://hdl.handle.net/20.500.11937/68221 |
| _version_ | 1848761775224258560 |
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| author | Saha, A. Khan, M. Sarker, Prabir Shaikh, Faiz Pramanik, Alokesh |
| author_facet | Saha, A. Khan, M. Sarker, Prabir Shaikh, Faiz Pramanik, Alokesh |
| author_sort | Saha, A. |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Alkali-silica reaction (ASR) of reactive aggregates is a major durability concern of concrete. The use of fly ash as a supplementary cementing material (SCM) shows a reliable way to control ASR expansion. This paper investigates the recent findings on effects of coal fly ash as a SCM on ASR of reactive aggregates. ASR is the reaction of amorphous silica of aggregates with highly alkaline pore solution in the binder matrix producing an expansive gel. The use of fly ash as cement replacement reduces pH of the pore solution by alkali binding and thus reduces the aggregate dissolution rate and swelling pressure of the ASR gel. The efficiency of fly ash primarily depends on its chemical composition with low calcium fly ash being more effective in mitigation of ASR expansion. Based on the available literature, this paper also analyses the ASR mitigation mechanisms of fly ash and provides some recommendations for future research. The degree of aggregate reactivity measurement, effect of alumina in fly ash, swelling properties of ASR gel in presence of fly ash and the long-term alkali contribution of fly ash on ASR are of particular importance. |
| first_indexed | 2025-11-14T10:37:02Z |
| format | Journal Article |
| id | curtin-20.500.11937-68221 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T10:37:02Z |
| publishDate | 2018 |
| publisher | Elsevier BV |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-682212020-07-15T01:48:16Z The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review Saha, A. Khan, M. Sarker, Prabir Shaikh, Faiz Pramanik, Alokesh Alkali-silica reaction (ASR) of reactive aggregates is a major durability concern of concrete. The use of fly ash as a supplementary cementing material (SCM) shows a reliable way to control ASR expansion. This paper investigates the recent findings on effects of coal fly ash as a SCM on ASR of reactive aggregates. ASR is the reaction of amorphous silica of aggregates with highly alkaline pore solution in the binder matrix producing an expansive gel. The use of fly ash as cement replacement reduces pH of the pore solution by alkali binding and thus reduces the aggregate dissolution rate and swelling pressure of the ASR gel. The efficiency of fly ash primarily depends on its chemical composition with low calcium fly ash being more effective in mitigation of ASR expansion. Based on the available literature, this paper also analyses the ASR mitigation mechanisms of fly ash and provides some recommendations for future research. The degree of aggregate reactivity measurement, effect of alumina in fly ash, swelling properties of ASR gel in presence of fly ash and the long-term alkali contribution of fly ash on ASR are of particular importance. 2018 Journal Article http://hdl.handle.net/20.500.11937/68221 10.1016/j.conbuildmat.2018.03.183 Elsevier BV fulltext |
| spellingShingle | Saha, A. Khan, M. Sarker, Prabir Shaikh, Faiz Pramanik, Alokesh The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review |
| title | The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review |
| title_full | The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review |
| title_fullStr | The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review |
| title_full_unstemmed | The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review |
| title_short | The ASR mechanism of reactive aggregates in concrete and its mitigation by fly ash: A critical review |
| title_sort | asr mechanism of reactive aggregates in concrete and its mitigation by fly ash: a critical review |
| url | http://hdl.handle.net/20.500.11937/68221 |