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Advanced Construction Materials and Technologies
a substantial improvement in the performance of these cementitious nanocomposites. There are reports which state that the 3 and 7 days compressive strengths of cementitious nanocomposites with 0.2 % of GO were increased by ≈36% and ≈42%, respectively, when compared to the control mix (Yang et al., 2017). Similarly, Tong et al. (2016) state, in their research, that the observed microstructure morphology shows that GO can significantly reshape the microstructure of the cement paste. However, the GO can cause a significant loss of the workability of the cement matrix, due essentially to the increase of its viscosity. This is mainly associated to its high specific surface area, (Wang et al., 2017).
4. Closing remarks
Theneedforcementmixeswithincreasinglyhigherperformancesand,ontheotherhand,the need to reduce the impact of the CI, through cutting of PC consumption, require industry and researchers to look for new solutions and materials. The use of GO in the development of new types of cementitious matrixes can lead to a significant improvement in the performance of the mortars and concretes used in the CI.
5. Acknowledgment
The authors acknowledge the support of the Instituto Politécnico de Lisboa (ISEL - IPL) through the funding of the scientific research project “Performance evaluation of self-compacting mortars with nanomaterials” (IPL/2018/ Nanomortar /ISEL)”.
6. References
OECD / Organisation for Economic Co-operation and Development (2018), Technology Roadmap - Low-Carbon Transition in the Cement Industry, International Energy Agency (IEA) and the World Business Council on Sustainable Development (WBCSD), France, 66 p.
Chuah S., Pan Z., Sanjayan J. G., Wang C.M., Duan W.H. (2014), Nano reinforced cement and concrete composites andnewperspectivefromgrapheneoxide,Constructionand BuildingMaterials,Vol:73,pp:113-124.
Yang H., Monasterio M., Cui H., Han N. (2017), Experimental study of the effects of graphene oxide on microstructure and properties of cement paste composite, Composites Part A: Applied Science and Manufacturing, Vol: 102, pp: 263-272.
Tong T., Fan Z., Liu Q., Wang S., Tan S., Yu Q. (2016), Investigation of the effects of graphene and graphene oxide nanoplatelets on the micro- and macro-properties of cementitious materials, Construction and Building Materials, , Vol: 106, pp: 102-114.
Wang Q., Cui X., Wang J.; Li S. Lv C., Dong Y. (2017), Effect of fly ash on rheological properties of graphene oxide cement paste, Construction and Building Materials, Vol: 138, pp: 35-44.
M o h a m e d Saafi M., Tang L., Fung J., Rahman M., Liggat J. (2015), Enhanced properties of graphene/fly ash geopolymeric composite cement, Cement and Concrete Research, Vol: 67, pp: 292-299.
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