Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint
In this paper, different types and particle sizes of nanoclay (nano-metakaolin—NMK—and nano-attapulgite—NMA—clay) were selected to study the effect of nanoclay on the properties of cement-based cementitious materials. The stability of different nanoclay dispersions was analyzed. The effects of nanoc...
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MDPI AG
2022-09-01
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| Series: | Buildings |
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| Online Access: | https://www.mdpi.com/2075-5309/12/9/1459 |
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| author | Guangying Liu Shiyi Zhang Yingfang Fan Surendra P. Shah |
| author_facet | Guangying Liu Shiyi Zhang Yingfang Fan Surendra P. Shah |
| author_sort | Guangying Liu |
| collection | DOAJ |
| description | In this paper, different types and particle sizes of nanoclay (nano-metakaolin—NMK—and nano-attapulgite—NMA—clay) were selected to study the effect of nanoclay on the properties of cement-based cementitious materials. The stability of different nanoclay dispersions was analyzed. The effects of nanoclay on the mechanical properties and cracking behavior of cement mortar were discussed. The crack propagation behavior of nanoclay cement mortar was analyzed by flat knife-edge induced constraint and ring constraint experiments. The research shows that the degree of aggregation of NMA particles is lower than that of NMK. The larger the particle size of NMA, the lower the degree of particle aggregation. The larger the particle size of NMK, the lower the degree of particle aggregation in water. NMK has the best improvement effect on cement mortar. The smaller the particle size, the more pronounced the improvement effect. The flexural strength ratio, compressive strength ratio, and elastic modulus ratio of 7 d and 28 d are 76.7%, 67.4%, and 61.2%, respectively. In the flat plate cracking experiment, the maximum crack width of NMK-3 and NMA-2 was reduced by 33.3% and 25.0%, respectively, compared with ordinary cement mortar. The maximum crack length was reduced by 55.1% and 33.1% compared with cement mortar. In the ring constraint experiment, the total cracked area of NMK-1, NMA-1, NMK-3, and NMA-2 rings increased by 64.3%, 45.0%, 92.7%, and 49.7%, respectively, compared with ordinary cement mortar rings after 60 days. NMK can advance the cracking time of cement mortar, but it can inhibit the generation and development of cracks and refine the crack width. |
| first_indexed | 2024-03-10T00:31:56Z |
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| id | doaj.art-d6ca6fb651764e12bd9148e1379172ee |
| institution | Directory Open Access Journal |
| issn | 2075-5309 |
| language | English |
| last_indexed | 2024-03-10T00:31:56Z |
| publishDate | 2022-09-01 |
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| series | Buildings |
| spelling | doaj.art-d6ca6fb651764e12bd9148e1379172ee2023-11-23T15:24:58ZengMDPI AGBuildings2075-53092022-09-01129145910.3390/buildings12091459Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under RestraintGuangying Liu0Shiyi Zhang1Yingfang Fan2Surendra P. Shah3School of Civil and Architectural Engineering, Chuzhou University, Chuzhou 239000, ChinaSchool of Civil Engineering and Architecture, Shandong University of Technology, Zibo 255000, ChinaInstitute of Road and Bridge Engineering, Dalian Maritime University, Dalian 116026, ChinaDepartment of Civil and Environmental Engineering, Northwestern University, Evanston, IL 60208, USAIn this paper, different types and particle sizes of nanoclay (nano-metakaolin—NMK—and nano-attapulgite—NMA—clay) were selected to study the effect of nanoclay on the properties of cement-based cementitious materials. The stability of different nanoclay dispersions was analyzed. The effects of nanoclay on the mechanical properties and cracking behavior of cement mortar were discussed. The crack propagation behavior of nanoclay cement mortar was analyzed by flat knife-edge induced constraint and ring constraint experiments. The research shows that the degree of aggregation of NMA particles is lower than that of NMK. The larger the particle size of NMA, the lower the degree of particle aggregation. The larger the particle size of NMK, the lower the degree of particle aggregation in water. NMK has the best improvement effect on cement mortar. The smaller the particle size, the more pronounced the improvement effect. The flexural strength ratio, compressive strength ratio, and elastic modulus ratio of 7 d and 28 d are 76.7%, 67.4%, and 61.2%, respectively. In the flat plate cracking experiment, the maximum crack width of NMK-3 and NMA-2 was reduced by 33.3% and 25.0%, respectively, compared with ordinary cement mortar. The maximum crack length was reduced by 55.1% and 33.1% compared with cement mortar. In the ring constraint experiment, the total cracked area of NMK-1, NMA-1, NMK-3, and NMA-2 rings increased by 64.3%, 45.0%, 92.7%, and 49.7%, respectively, compared with ordinary cement mortar rings after 60 days. NMK can advance the cracking time of cement mortar, but it can inhibit the generation and development of cracks and refine the crack width.https://www.mdpi.com/2075-5309/12/9/1459nanoclaycement-based materialsearly crackingdispersionshrinkage |
| spellingShingle | Guangying Liu Shiyi Zhang Yingfang Fan Surendra P. Shah Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint Buildings nanoclay cement-based materials early cracking dispersion shrinkage |
| title | Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint |
| title_full | Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint |
| title_fullStr | Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint |
| title_full_unstemmed | Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint |
| title_short | Study on Shrinkage Cracking Morphology of Cement Mortar with Different Nanoclay Particles under Restraint |
| title_sort | study on shrinkage cracking morphology of cement mortar with different nanoclay particles under restraint |
| topic | nanoclay cement-based materials early cracking dispersion shrinkage |
| url | https://www.mdpi.com/2075-5309/12/9/1459 |
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