MWCNT and CNF Cementitious Nanocomposites for Enhanced Strength and Toughness
Cementitious nanocomposites reinforced with carbon fibers at the nanoscale were fabricated and tested, exhibiting remarkably improved mechanical and fracture properties. The cementitious nanocomposites were reinforced with well dispersed multiwall carbon nanotubes (MWCNTs) and carbon nanofibers (CNFs). A dispersion method involving the application of ultrasonic energy and the use of a superplasticizer was employed to prepare the nanoscale fiber suspensions. Flexural strength and Young’s modulus were experimentally investigated and compared with similarly processed reference cement based mixes without the nano-reinforcement. The nanocomposites’ fracture properties were also determined using the two parameter fracture model (TPFM). The excellent reinforcing capability of MWCNTs and CNFs is demonstrated by a significant improvement in flexural strength (87 % for MWCNTs and 106 % for CNFs reinforcement), Young’s modulus (100 %), and fracture toughness (86 % for MWCNTs and 119 % for CNFs reinforcement).
KeywordsMulti-walled carbon nanotubes Carbon nanofibers Mortars Fracture mechanics Young’s modulus
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”.
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