Advanced cement based nanocomposites reinforced with MWCNTs and CNFs

Abstract

Cementitious materials reinforced with well dispersed multiwall carbon nanotubes (MWCNTs) and carbon nanofibers (CNFs) at the nanoscale were fabricated and tested. The MWCNTs and CNFs were dispersed by the application of ultrasonic energy and the use of a superplasticizer. Mechanical and fracture properties including flexural strength, Young’s modulus, flexural and fracture toughness were measured and compared with similarly processed reference cement based mixes without the nano-reinforcement. The MWCNTs and CNFs reinforced mortars exhibited superior properties demonstrated by a significant improvement in flexural strength (106%), Young’s modulus (95%), flexural toughness (105%), effective crack length (30%) and fracture toughness (120%).

Keywords

multi-walled carbon nanotubes / carbon nanofibers / mortars / toughness / Young’s modulus

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Acknowledgements

The authors would like to acknowledge the financial support of the National Strategic Reference Framework (NSRF) Research Funding Program ‘‘Thales-Democritus University of Thrace-Center for Multifunctional Nanocomposite Construction Materials’’ (MIS379496) funded by the European Union (European Social Fund—ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” .

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg