Print Email Facebook Twitter Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation Title Carbonation Behavior of Engineered Cementitious Composites under Coupled Sustained Flexural Load and Accelerated Carbonation Author Zhang, Hongzhi (Shandong University) Shao, Yingxuan (Shandong University) Zhang, Ning (Shandong Hi-Speed Engineering Test CO) Tawfek, Abdullah M. (Shandong University; Sana'a University) Guan, Yanhua (Shandong University) Sun, Renjuan (Shandong University) Tian, Changjin (Shandong University) Šavija, B. (TU Delft Materials and Environment) Date 2022 Abstract 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. Subject accelerated carbonationengineered cementitious compositesmicrohardnessmicrostructuresustained flexural load To reference this document use: http://resolver.tudelft.nl/uuid:4f3e3b25-ce23-47b3-86a9-5523be3daa1a DOI https://doi.org/10.3390/ma15186192 ISSN 1996-1944 Source Materials, 15 (18) Part of collection Institutional Repository Document type journal article Rights © 2022 Hongzhi Zhang, Yingxuan Shao, Ning Zhang, Abdullah M. Tawfek, Yanhua Guan, Renjuan Sun, Changjin Tian, B. Šavija Files PDF materials_15_06192.pdf 3.27 MB Close viewer /islandora/object/uuid:4f3e3b25-ce23-47b3-86a9-5523be3daa1a/datastream/OBJ/view