Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation
Engineered cementitious composites (ECCs) belong to a broad class of fibre-reinforced concrete. They incorporate synthetic polyvinyl alcohol (PVA) fibres, cement, fly ash and fine aggregates, and are designed to have a tensile strain capacity typically beyond 3%. This paper presents an investigation...
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| author | Hongzhi Zhang Yingxuan Shao Ning Zhang Abdullah M. Tawfek Yanhua Guan Renjuan Sun Changjin Tian Branko Šavija |
| author_facet | Hongzhi Zhang Yingxuan Shao Ning Zhang Abdullah M. Tawfek Yanhua Guan Renjuan Sun Changjin Tian Branko Šavija |
| author_sort | Hongzhi Zhang |
| collection | DOAJ |
| description | Engineered cementitious composites (ECCs) belong to a broad class of fibre-reinforced concrete. They incorporate synthetic polyvinyl alcohol (PVA) fibres, cement, fly ash and fine aggregates, and are designed to have a tensile strain capacity typically beyond 3%. This paper presents an investigation on the carbonation behaviour of engineered cementitious composites (ECCs) under coupled sustained flexural load and accelerated carbonation. The carbonation depth under a sustained stress level of 0, 0.075, 0.15, 0.3 and 0.6 relative to flexural strength was measured after 7, 14 and 28 days of accelerated carbonation. Thermogravimetric analysis, mercury intrusion porosimetry and microhardness measurements were carried out to show the coupled influence of sustained flexural load and accelerated carbonation on the changes of the mineral phases, porosity, pore size distribution and microhardness along the carbonation profile. A modified carbonation depth model that can be used to consider the coupled effect of flexural tensile stress and carbonation time was proposed. The results show that an exponential relationship can be observed between stress influence coefficient and flexural tensile stress level in the carbonation depth model of ECC, which is different when using plain concrete. Areas with a higher carbonation degree have greater microhardness, even under a large sustained load level, as the carbonation process refines the pore structure and the fibre bridges the crack effectively. |
| first_indexed | 2024-03-09T23:19:53Z |
| format | Article |
| id | doaj.art-ce02363ba2d84af9922549a05be6ccf6 |
| institution | Directory Open Access Journal |
| issn | 1996-1944 |
| language | English |
| last_indexed | 2024-03-09T23:19:53Z |
| publishDate | 2022-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Materials |
| spelling | doaj.art-ce02363ba2d84af9922549a05be6ccf62023-11-23T17:29:26ZengMDPI AGMaterials1996-19442022-09-011518619210.3390/ma15186192Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated CarbonationHongzhi Zhang0Yingxuan Shao1Ning Zhang2Abdullah M. Tawfek3Yanhua Guan4Renjuan Sun5Changjin Tian6Branko Šavija7School of Qilu Transportation, Shandong University, Jinan 250002, ChinaSchool of Qilu Transportation, Shandong University, Jinan 250002, ChinaShandong Hi-Speed Engineering Test Co., Ltd., Jinan 250002, ChinaSchool of Qilu Transportation, Shandong University, Jinan 250002, ChinaSchool of Qilu Transportation, Shandong University, Jinan 250002, ChinaSchool of Qilu Transportation, Shandong University, Jinan 250002, ChinaSchool of Qilu Transportation, Shandong University, Jinan 250002, ChinaMicrolab, Faculty of Civil Engineering and Geosciences, Delft University of Technology, 2628 CN Delft, The NetherlandsEngineered cementitious composites (ECCs) belong to a broad class of fibre-reinforced concrete. They incorporate synthetic polyvinyl alcohol (PVA) fibres, cement, fly ash and fine aggregates, and are designed to have a tensile strain capacity typically beyond 3%. This paper presents an investigation on the carbonation behaviour of engineered cementitious composites (ECCs) under coupled sustained flexural load and accelerated carbonation. The carbonation depth under a sustained stress level of 0, 0.075, 0.15, 0.3 and 0.6 relative to flexural strength was measured after 7, 14 and 28 days of accelerated carbonation. Thermogravimetric analysis, mercury intrusion porosimetry and microhardness measurements were carried out to show the coupled influence of sustained flexural load and accelerated carbonation on the changes of the mineral phases, porosity, pore size distribution and microhardness along the carbonation profile. A modified carbonation depth model that can be used to consider the coupled effect of flexural tensile stress and carbonation time was proposed. The results show that an exponential relationship can be observed between stress influence coefficient and flexural tensile stress level in the carbonation depth model of ECC, which is different when using plain concrete. Areas with a higher carbonation degree have greater microhardness, even under a large sustained load level, as the carbonation process refines the pore structure and the fibre bridges the crack effectively.https://www.mdpi.com/1996-1944/15/18/6192engineered cementitious compositessustained flexural loadaccelerated carbonationmicrostructuremicrohardness |
| spellingShingle | Hongzhi Zhang Yingxuan Shao Ning Zhang Abdullah M. Tawfek Yanhua Guan Renjuan Sun Changjin Tian Branko Šavija Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation Materials engineered cementitious composites sustained flexural load accelerated carbonation microstructure microhardness |
| title | Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation |
| title_full | Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation |
| title_fullStr | Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation |
| title_full_unstemmed | Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation |
| title_short | Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation |
| title_sort | carbonation behavior of engineered cementitious composites under coupled sustained flexural load and accelerated carbonation |
| topic | engineered cementitious composites sustained flexural load accelerated carbonation microstructure microhardness |
| url | https://www.mdpi.com/1996-1944/15/18/6192 |
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