Nickel plated carbon nanotubes reinforcing concrete composites: from nano/micro structures to macro mechanical properties
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Publication date
2021-02Author
Ashour, Ashraf
Keyword
Carbon nanotubesCarbon nanofibers
Carbon nanofibres
Carbon nanotubes and nanofibers
Carbon nanotubes and nanofibres
Nanocomposites
Mechanical properties
Microstructural analysis
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© 2020 Elsevier. Reproduced in accordance with the publisher's self-archiving policy. This manuscript version is made available under the CC-BY-NC-ND 4.0 license.Peer-Reviewed
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Owing to their small size, good wettability, uniform dispersion ability and high thermal properties, the nickel-plated carbon nanotubes (Ni-CNTs) with different aspect ratios are used to reinforce reactive powder concrete (RPC) through modifying the nano/micro- structural units of concrete. Incorporating only 0.075 vol% of Ni-CNTs (0.03 vol% of CNTs) can significantly increase mechanical properties of RPC. The enhancement effect on compressive strength caused by the incorporation of Ni-CNTs with aspect ratio of 1000 reaches 26.8%/23.0 MPa, mainly benefiting from the high polymerization C-S-H gels, low porosity, and refined pore structure. The 33.5%/1.92 MPa increases of flexural strength can be attributed to the decrease of large pore, original cracks, molar ratio of CaO to SiO2, and gel water content when Ni-CNTs with aspect ratio of 125 are added. Ni-CNTs with aspect ratio of 1500 have the largest utilization rate of being pulled-out, resulting from the improvement of dispersibility and the pining effect of nickel coating and then leading to the increased toughness. Therefore, incorporating Ni-CNTs can fundamentally modify the nano/micro- scale structural nature of RPC, providing a bottom-up approach for controlling the properties of RPC.Version
Accepted manuscriptCitation
Dong S, Wang D, Ashour AF et al (2021) Nickel plated carbon nanotubes reinforcing concrete composites: from nano/micro structures to macro mechanical properties. Composites Part A: Applied Science and Manufacturing. 141: 106228.Link to Version of Record
https://doi.org/10.1016/j.compositesa.2020.106228Type
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