Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures

Cementitious composites are the most widely used construction materials; however, their poor durability necessitates frequent monitoring and repairs. The emergence of self-sensing composites could reduce the need for costly and time-consuming structural inspections. Natural graphite, due to its low...

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Main Authors: Ioanna Papanikolaou, Chrysoula Litina, Amir Zomorodian, Abir Al-Tabbaa
Format: Article
Language:English
Published: MDPI AG 2020-12-01
Series:Materials
Subjects:
Online Access:https://www.mdpi.com/1996-1944/13/24/5833
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author Ioanna Papanikolaou
Chrysoula Litina
Amir Zomorodian
Abir Al-Tabbaa
author_facet Ioanna Papanikolaou
Chrysoula Litina
Amir Zomorodian
Abir Al-Tabbaa
author_sort Ioanna Papanikolaou
collection DOAJ
description Cementitious composites are the most widely used construction materials; however, their poor durability necessitates frequent monitoring and repairs. The emergence of self-sensing composites could reduce the need for costly and time-consuming structural inspections. Natural graphite, due to its low cost and wide availability, is a promising additive to generate an electrically conductive network which could ultimately lead to a self-sensing mechanism. Despite several studies using natural graphite as a conductive additive, the effect of its fineness on the cementitious composite’s performance has not been explored. This study experimentally investigated the effect of three graphite products of varying fineness on the early age, mechanical, and electrical conductivity performance of cement pastes. The fluidity of the graphite-cement paste reduced significantly with increasing graphite fineness, and graphite did not affect the cement hydration. The finer the graphite, the lower the effect on the mechanical performance, as confirmed by compressive strength testing and micro-indentation. Electrical conductivity testing showed that the percolation threshold depended on the graphite fineness and was found at ~20 wt % for the fine and medium graphite, while it increased to 30–40 wt % for the coarse graphite. This is the first study that has investigated holistically the effect of graphite fineness on the performance of cement pastes and will pave the way for using this material as an additive for self-sensing structures.
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spelling doaj.art-1dc7349ce20c4e4c99945ec5e811ba8a2023-11-21T01:55:23ZengMDPI AGMaterials1996-19442020-12-011324583310.3390/ma13245833Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing StructuresIoanna Papanikolaou0Chrysoula Litina1Amir Zomorodian2Abir Al-Tabbaa3Department of Engineering, University of Cambridge, Trumpington St., Cambridge CB2 1PZ, UKDepartment of Engineering, University of Cambridge, Trumpington St., Cambridge CB2 1PZ, UKDepartment of Engineering, University of Cambridge, Trumpington St., Cambridge CB2 1PZ, UKDepartment of Engineering, University of Cambridge, Trumpington St., Cambridge CB2 1PZ, UKCementitious composites are the most widely used construction materials; however, their poor durability necessitates frequent monitoring and repairs. The emergence of self-sensing composites could reduce the need for costly and time-consuming structural inspections. Natural graphite, due to its low cost and wide availability, is a promising additive to generate an electrically conductive network which could ultimately lead to a self-sensing mechanism. Despite several studies using natural graphite as a conductive additive, the effect of its fineness on the cementitious composite’s performance has not been explored. This study experimentally investigated the effect of three graphite products of varying fineness on the early age, mechanical, and electrical conductivity performance of cement pastes. The fluidity of the graphite-cement paste reduced significantly with increasing graphite fineness, and graphite did not affect the cement hydration. The finer the graphite, the lower the effect on the mechanical performance, as confirmed by compressive strength testing and micro-indentation. Electrical conductivity testing showed that the percolation threshold depended on the graphite fineness and was found at ~20 wt % for the fine and medium graphite, while it increased to 30–40 wt % for the coarse graphite. This is the first study that has investigated holistically the effect of graphite fineness on the performance of cement pastes and will pave the way for using this material as an additive for self-sensing structures.https://www.mdpi.com/1996-1944/13/24/5833cementgraphiteadditiveselectrical conductivityself-sensing
spellingShingle Ioanna Papanikolaou
Chrysoula Litina
Amir Zomorodian
Abir Al-Tabbaa
Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures
Materials
cement
graphite
additives
electrical conductivity
self-sensing
title Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures
title_full Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures
title_fullStr Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures
title_full_unstemmed Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures
title_short Effect of Natural Graphite Fineness on the Performance and Electrical Conductivity of Cement Paste Mixes for Self-Sensing Structures
title_sort effect of natural graphite fineness on the performance and electrical conductivity of cement paste mixes for self sensing structures
topic cement
graphite
additives
electrical conductivity
self-sensing
url https://www.mdpi.com/1996-1944/13/24/5833
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AT amirzomorodian effectofnaturalgraphitefinenessontheperformanceandelectricalconductivityofcementpastemixesforselfsensingstructures
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