Pore Structure and Durability of Cement-based Composites Doped with Graphene Nanoplatelets

来源 :中国大坝工程学会水库泥沙处理与资源利用技术专业委员会成立大会 | 被引量 : 0次 | 上传用户:etoy
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  The paper presents the effect of graphene nanoplatelets (GNPs) on the pore structure and chloride permeability of cement paste with a water to cement ratio of 0.35.The influence of GNPs on the hydration degree,microstructure and chloride permeability of the cement paste is systematically investigated.The experimental results show that the addition of GNPs refined the pore structure and decreased the chloride migration coefficient.It is clearly indicated that the very low fraction of GNPs (0.1%) can effectively hinder the ingress of chloride ions.Additionally,the sulfate corrosion is also enhanced by GNPs with a moderate of 0.1%.The improvement chloride permeability and is not only attribute to the excellent properties of GNPs itself but also the higher hydration degree,lower porosity and the effect of GNPs such as crack arresting,and barrier effect.It is concluded that GNPs has a great potential for reinforcing the durability of cement paste.
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