Title:
Carbon Nanotubes Reinforced Concrete
Author(s):
Z.S. Metaxa, M.S. Konsta-Gdoutos, and S.P. Shah
Publication:
Symposium Paper
Volume:
267
Issue:
Appears on pages(s):
11-20
Keywords:
carbon nanotubes; mechanical properties; nanofiber reinforcement; nanoindentation; scanning electron microscopy.
DOI:
10.14359/51663279
Date:
10/1/2009
Abstract:
In this study, the development of cementitious nanocomposites reinforced with multiwall carbon nanotubes (MWCNTs) at water-cement ratios of 0.3 and 0.5 was investigated. The effect of carbon nanotubes at low concentrations on the fracture properties, nanoscale properties and microstructure of the nanocomposite materials was studied. The morphology and the microstructure of nanocomposite samples were investigated using an ultra high resolution field emission scanning electron microscope. A special type of nanoindenter, along with in-place scanning probe microscopy imaging, was used to determine the local nanoscale mechanical properties. The results show that the mechanical properties of cementitious matrices can be increased by the incorporation of very low amounts of CNTs. Nanoimaging of the fracture surfaces of cement nanocomposites have shown that CNTs reinforce cement paste by bridging the nanocracks and pores. Additionally, nanoindentation results suggest that CNTs modify and reinforce the nanostructure of cement paste by increasing the amount of high stiffness C-S-H and reducing the porosity.