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Nanotechnology for Improved Concrete Performance
ACI SP-335
Organization:
ACI - American Concrete Institute
Year: 2019
Abstract: In cold regions, freezing temperatures limit the construction season to few months, usually between May and September.
The use of nanoparticles, which have high specific surface and vigorous reactivity, may potentially enhance the performance of concrete placed at low temperatures.
Therefore, this study focused on developing concrete mixtures incorporating nano-silica which were mixed, placed and cured at -5°C (23°F) without any insulation or protection targeting field applications in late fall and early spring periods.
Eight mixtures incorporating general use (GU) cement, fly ash (up to 25%), and nano-silica (up to 4%) were tested for this purpose, with waterto- binder ratios of 0.32 and 0.4.
All mixtures contained a combination of calcium nitrate and calcium nitrite as an antifreeze admixture.
Testing involved concrete setting time (placement), 7 and 28 days compressive strengths (hardened properties) and resistance to freezing-thawing cycles (durability).
Moreover, mercury intrusion porosimetry, thermal analysis and scanning electron microscopy were performed to corroborate the trends from the macro-scale tests.
It was found that nano-silica significantly improved the overall performance of concrete placed and cured at -5°C (23°F), which implicates its promising use for construction applications under low temperatures
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Nanotechnology for Improved Concrete Performance
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| contributor author | ACI - American Concrete Institute | |
| date accessioned | 2020-07-27T21:31:47Z | |
| date available | 2020-07-27T21:31:47Z | |
| date issued | 2019 | |
| identifier other | EXSBJGAAAAAAAAAA.pdf | |
| identifier uri | http://yse.yabesh.ir/std;jsein=autho4/handle/yse/280577 | |
| description abstract | In cold regions, freezing temperatures limit the construction season to few months, usually between May and September. The use of nanoparticles, which have high specific surface and vigorous reactivity, may potentially enhance the performance of concrete placed at low temperatures. Therefore, this study focused on developing concrete mixtures incorporating nano-silica which were mixed, placed and cured at -5°C (23°F) without any insulation or protection targeting field applications in late fall and early spring periods. Eight mixtures incorporating general use (GU) cement, fly ash (up to 25%), and nano-silica (up to 4%) were tested for this purpose, with waterto- binder ratios of 0.32 and 0.4. All mixtures contained a combination of calcium nitrate and calcium nitrite as an antifreeze admixture. Testing involved concrete setting time (placement), 7 and 28 days compressive strengths (hardened properties) and resistance to freezing-thawing cycles (durability). Moreover, mercury intrusion porosimetry, thermal analysis and scanning electron microscopy were performed to corroborate the trends from the macro-scale tests. It was found that nano-silica significantly improved the overall performance of concrete placed and cured at -5°C (23°F), which implicates its promising use for construction applications under low temperatures | |
| language | English | |
| title | Nanotechnology for Improved Concrete Performance | en |
| title | ACI SP-335 | num |
| type | standard | |
| page | 144 | |
| status | Active | |
| tree | ACI - American Concrete Institute:;2019 | |
| contenttype | fulltext |