Effect of Nanofibers on the Behavior of Cement Mortar and Concrete

The main objective of this paper is study the influence
of carbon nano-tubes fibers and nano silica fibers on the
characteristic compressive strength and flexural strength on concrete
and cement mortar. Twelve tested specimens were tested with square
section its dimensions (4040 160) mm, divided into four groups.
The first and second group studied the effect of carbon nano-tubes
(CNTs) fibers with different percentage equal to 0.0, 0.11%, 0.22%,
and 0.33% by weight of cement and effect of nano-silica (nS) fibers
with different percentages equal to 0.0, 1.0%, 2.0%, and 3.0% by
weight of cement on the cement mortar. The third and fourth groups
studied the effect of CNTs fiber with different percentage equal to
0.0%, 0.11%, and 0.22% by weight of cement, and effect of nS fibers
with different percentages were equal to 0.0%, 1.0%, and 2.0% by
weight of cement on the concrete. The compressive strength and
flexural strength at 7, 28, and 90 days is determined. From analysis of
tested results concluded that the nano-fibers is more effective when
used with cement mortar more than used with concrete because of
increasing the surface area, decreasing the pore and the collection of
nano-fibers. And also by adding nano-fibers the improvement of
flexural strength of concrete and cement mortar is more than
improvement of compressive strength.

• Mostafa Osman
• Ata El-kareim Shoeib

• Carbon nano-tubes fibers
• nano-silica (nS) fibers
• compressive strength
• flexural.

[1] Quercia G., and Brouwers H. J. H, “Application of nanosilica (nS) in
concrete mixtures,”8th fib PhD Symposium inKgs. Lyngby, Denmark,
2010, p.6.
[2] Plassard, C, Lesniewska, E, Pochard, I, Nonat, A.,” Investigation of the
surface structure and elastic properties of calcium silicate hydrates at the
nano-scale,” Ultramicroscopyvol.100, no.3-4, 2005, pp. 331-338.
[3] Porro, A., Dolado, J.S., Campillo, I., Erkizia, E., de Miguel, Y.,Sáez de
Ibarra, Y., Ayuela, A., “Effects of nano-silica additions on cement
pastes; Applications of nanotechnology in concrete design,” Thomas
Telford; London, 2005.
[4] Ismael flores-vivian, Rani G.K. Pradoto, Mohamad rezamoini,
Konstantin sobolev, “the use of nanoparticles to improve the
performance of concrete,”Brno, Czech Republic, EU, vol.10, 2013,pp.
16 -18.
[5] Collepardi, M., Ogoumah-Olagot, J.J., Skarp, U., Troli, R., “Influence of
amorphous colloidal silica on the properties of self-compacting
concretes,” Proceedings of the International Conference, Dundee, UK,
2002, pp. 473 - 483.
[6] Chan L. Y. and Andrews B., “Finite element analysis of carbon
nanotube/cement composite with degraded bond strength,”
Computational Materials Science, vol.47,no.4, 2010, pp.994-1004.
[7] Metaxa Z. S., and et al., “Carbon nano reinforced concrete,” ACI Special
Publications Nanotechnology of Concrete The Next Big Thing is Small
SP, vol. 267, no. 2, 2009, pp.11-20.
[8] Ata El-kareim Shoeib, “Effect of nanotube carbon fibers in fracture
mechanics of reinforced concrete structure, "Fifth International
Conference on nano-technology in construction (NTC 2013), 2013, p.9.