Carbon dioxide curing of mortar produced with thermally activated recycled cement

被引：0
作者：
Li Y. [1 ]
Wang H. [1 ]
Sun H. [2 ]
Liu T. [1 ]
机构：
[1] School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen
[2] China Construction Science and Technology Group Co.,Ltd., Beijing
来源：
Dongnan Daxue Xuebao (Ziran Kexue Ban)/Journal of Southeast University (Natural Science Edition) | 2024年 / 54卷 / 01期
关键词：
carbon dioxide curing; low-pH; reactivated cementitious materials; silica fume;
D O I：
10.3969/j.issn.1001-0505.2024.01.011
中图分类号：
学科分类号：
摘要：
A method for carbon dioxide curing of mortar produced with thermally activated recycled cement was proposed to improve the resource utilization for waste concrete and reduce the overall carbon dioxide emission during concrete preparation. The waste cement paste containing 0% to 30% silica fume was thermally activated at 800 ℃ to obtain reactivated cementitious materials with different calcium-to-silica ratios. The mortar with low alkalinity was prepared by gradient carbon dioxide curing. The compressive strength,phase assemblage,and microstructure of mortars were analyzed. The results show that the mineral composition of the reactivated cementitious materials obtained by mixing 0% and 10% silica fume is tricalcium silicate (C3S),β-dicalcium silicate (β-C2S),and α′-C2S,and a large amount of calcite and vaterite is formed after carbon dioxide curing. However,the mineral composition is mainly α′-C2S and monocalcium silicate (CS)after adding 20% and 30% silica fume,and the carbonation products are mainly calcite and aragonite after carbon dioxide curing. The compressive strength of the mortar samples after carbon dioxide curing is higher than 45 MPa,and the compressive strength of the mortar samples produced with reactivated cementitious materials containing 20% silica fume achieves 64. 7 MPa. The pH of the mortar specimens is reduced to 9. 4,which can effectively mitigate the performance degradation of fiber reinforced polymer in highly alkaline environments. © 2024 Southeast University. All rights reserved.
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页码：80 / 88
页数：8
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共 47 条
  • [1] Li L K, Liu Q, Huang T Y, Et al., Mineralization and utilization of CO<sub>2</sub> in construction and demolition wastes recycling for building materials:A systematic review of recycled concrete aggregate and recycled hardened cement powder [J], Separation and Purification Technology, 298, (2022)
  • [2] Costa F N, Riveiro D V., Evaluation of phase formation and physical-mechanical properties of Portland cements produced with civil construction waste [J], Cement, 5, (2021)
  • [3] Andrew R M., Global CO<sub>2</sub> emissions from cement production,1928—2018 [J], Earth System Science Data, 11, 4, pp. 1675-1710, (2019)
  • [4] Liang C F, Lu N, Ma H W, Et al., Carbonation behavior of recycled concrete with CO<sub>2</sub> -curing recycled aggregate under various environments [J], Utilization, 39, (2020)
  • [5] Jin R Y, Li B, Zhou T Y, Et al., An empirical study of perceptions towards construction and demolition waste recycling and reuse in China [J], Resources,Conservation and Recycling, 126, (2017)
  • [6] (2018)
  • [7] Sun L, Ren J L., Mechanical characteristics and parameter design of cement stabilized macadam containing building demolition waste, Journal of Southeast University (Natural Science Edition), 44, 5, pp. 1052-1056, (2014)
  • [8] Jiang Y, Ma Z H, Shen P L, Et al., Research progress on carbonation technologies for valorising waste concrete:A review [J], Journal of the Chinese Ceramic Society, 51, 9, (2023)
  • [9] Duan Z H, Hou S D, Pan Z S, Et al., Rheology of recycled fine aggregate concrete and its effect on strength and durability [J], Journal of Building Structures, 41, S2, (2020)
  • [10] Hu S G, He Y J., Preparation of regenerated binding material using waste concrete [J], Journal of the Chinese Ceramic Society, 32, 5, pp. 593-599, (2007)
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