TY - JOUR
T1 - Unlocking the role of recycled aggregates in the performance enhancement and CO2 capture of reactive magnesia cement formulations
AU - Pan, C.
AU - Song, Y.
AU - Wang, J.
AU - Zhan, S.
AU - Unluer, C.
AU - Ruan, S.
N1 - Funding Information:
The authors acknowledge the Zhejiang Provincial Natural Science Foundation (No. LY22E080001 ), the National Natural Science Foundation of China (No. 52108255 ) and Self-determined Project from State Key Laboratory of Clean Energy Utilization, Zhejiang University . The authors are also grateful for the assistance from Liying Chen at State Key Laboratory of Modern Optical Instruments (Zhejiang University), and Qiyang Li at School of Aeronautics and Astronautics (Zhejiang University) for performing the 3D interference microscope and the nanoindentation instrument, respectively.
Funding Information:
The authors acknowledge the Zhejiang Provincial Natural Science Foundation (No. LY22E080001), the National Natural Science Foundation of China (No. 52108255) and Self-determined Project from State Key Laboratory of Clean Energy Utilization, Zhejiang University. The authors are also grateful for the assistance from Liying Chen at State Key Laboratory of Modern Optical Instruments (Zhejiang University), and Qiyang Li at School of Aeronautics and Astronautics (Zhejiang University) for performing the 3D interference microscope and the nanoindentation instrument, respectively.
Publisher Copyright:
© 2023 Elsevier Ltd
PY - 2023/6/1
Y1 - 2023/6/1
N2 - The use of recycled aggregates (RCAs) could further enhance the sustainability of reactive magnesia cement (RMC) formulations, but the performances of RMC-RCA are still unknown to researchers. Therefore, in this study, the strength development of CO 2-cured RMC-RCA was explored for the first time, and the strength variation among groups was further interpreted by microstructural analyses. The initial results show that compared with samples with natural aggregates (NAs), a 28 d strength boost (i.e., 37 vs. 15 MPa) in RMC-RCA can be observed. The strength improved in RMC-RCA could be related to its refined microstructures, ITZs and larger carbonation depths, which resulted from the easiness of CO 2 penetration within samples. Then the presence of porous ITZs in RCA contributes to better CO 2 diffusion, as described in the proposed revised CO 2 diffusion model. Overall, while enabling a pronounced CO 2 capture potential of RMC concrete, this preliminary study could pave the path for the upcycling of RCAs in RMC concrete on a large scale.
AB - The use of recycled aggregates (RCAs) could further enhance the sustainability of reactive magnesia cement (RMC) formulations, but the performances of RMC-RCA are still unknown to researchers. Therefore, in this study, the strength development of CO 2-cured RMC-RCA was explored for the first time, and the strength variation among groups was further interpreted by microstructural analyses. The initial results show that compared with samples with natural aggregates (NAs), a 28 d strength boost (i.e., 37 vs. 15 MPa) in RMC-RCA can be observed. The strength improved in RMC-RCA could be related to its refined microstructures, ITZs and larger carbonation depths, which resulted from the easiness of CO 2 penetration within samples. Then the presence of porous ITZs in RCA contributes to better CO 2 diffusion, as described in the proposed revised CO 2 diffusion model. Overall, while enabling a pronounced CO 2 capture potential of RMC concrete, this preliminary study could pave the path for the upcycling of RCAs in RMC concrete on a large scale.
KW - Microstructural analysis
KW - Nanoindentation
KW - Pore structures
KW - Reactive magnesia cement
KW - Recycled aggregates
U2 - 10.1016/j.cemconres.2023.107148
DO - 10.1016/j.cemconres.2023.107148
M3 - Article
SN - 0008-8846
VL - 168
JO - Cement and Concrete Research
JF - Cement and Concrete Research
M1 - 107148
ER -