Single and combined effects of nano-SiO2, nano-Al2O3 and nano-Fe2O3 powders on compressive strength and capillary permeability of cement mortar containing silica fume

Abstract In this article, the single, binary and ternary effects of three nano-sized powders of the main oxides of cement (nano-SiO2, nano-Al2O3 and nano-Fe2O3) on the compressive strength and capillary permeability of cement mortars containing silica fume were investigated. The powder amounts were chosen at proportions corresponding to 0.5%, 1.25% and 2.5% of the binder amount. Compressive strength was determined for early age (3- and 7-day), standard age (28-day), and late age (56- and 180-day) mortars, while capillary permeability was determined for 180-day-old mortars only. It was concluded from the experimental results that the type and amount of nano the powders, and mortar production methods had a significant effect on the fresh and hardened properties of cement mortars. The nano-powders used singly or in combination increased the 28-day compressive strength of silica fume-containing mortars by up to 27%, with the exception of nano-SiO2 powder used at a proportion of 2.5%. However, the compressive strength values fluctuated at early and later ages. The best results for compressive strength and capillary permeability at the end of day 180 were obtained with 1.25% nano-Al2O3 powder in single uses, 0.5% nano-SiO2 + nano-Al2O3 powders in binary combinations, and 0.5% in ternary combination. However, it was determined that the interaction between the powders used in binary and ternary combinations led to negative effects on the physical–mechanical properties of the mortars. For this reason, nano-Al2O3 powder and single use were primarily recommended in cases where an increase in the performance of cement-based composites is desired. The findings of the experiments suggested the conclusion that the improvement in the mechanical and physical properties of mortars was caused by the rise in pozzolanic activity induced by the favorable influence of the powders rather than the filler effect.

[1]  A. Nazari,et al.  Splitting tensile strength of concrete using ground granulated blast furnace slag and SiO2 nanoparticles as binder , 2011 .

[2]  A. Nazari,et al.  THE EFFECTS OF SIO2 NANOPARTICLES ON PHYSICAL AND MECHANICAL PROPERTIES OF HIGH STRENGTH COMPACTING CONCRETE , 2010 .

[3]  A. Nazari,et al.  The effect of TiO2 nanoparticles on water permeability and thermal and mechanical properties of high strength self-compacting concrete , 2010 .

[4]  Jong-Bin Park,et al.  Characteristics of cement mortar with nano-SiO2 particles , 2007 .

[5]  J. Szwabowski,et al.  Influence of superplasticizers on rheological behaviour of fresh cement mortars , 2004 .

[6]  Ana Guerrero,et al.  Improvement of initial mechanical strength by nanoalumina in belite cements , 2007 .

[7]  M. Sonebi.  Optimization of Cement Grouts Containing Silica Fume and Viscosity Modifying Admixture , 2010 .

[8]  Y. Qing,et al.  Influence of nano-SiO2 addition on properties of hardened cement paste as compared with silica fume , 2007 .

[9]  Dachamir Hotza,et al.  Effect of nano-silica on rheology and fresh properties of cement pastes and mortars , 2009 .

[10]  Gengying Li,et al.  Properties of high-volume fly ash concrete incorporating nano-SiO2 , 2004 .

[11]  Mohamad Amran Mohd Salleh,et al.  Experimental investigation of the size effects of SiO2 nano-particles on the mechanical properties of binary blended concrete , 2010 .

[12]  Tao Ji,et al.  Preliminary study on the water permeability and microstructure of concrete incorporating nano-SiO2 , 2005 .

[13]  J. Ou,et al.  Microstructure of cement mortar with nano-particles , 2004 .

[14]  Darko Krizan,et al.  Effects of dosage and modulus of water glass on early hydration of alkali–slag cements , 2002 .

[15]  Zhenhua Li,et al.  Investigations on the preparation and mechanical properties of the nano-alumina reinforced cement composite , 2006 .

[16]  A. Nazari,et al.  The effects of TiO2 nanoparticles on physical, thermal and mechanical properties of concrete using ground granulated blast furnace slag as binder , 2011 .

[17]  Ali Nazari,et al.  The effects of zinc dioxide nanoparticles on flexural strength of self-compacting concrete , 2011 .

[18]  B. Chattopadhyay,et al.  Use of microorganism to improve the strength of cement mortar , 2005 .

[19]  Ali Nazari,et al.  IMPROVEMENT COMPRESSIVE STRENGTH OF CONCRETE IN DIFFERENT CURING MEDIA BY AL2O3 NANOPARTICLES , 2011 .

[20]  Hui Li,et al.  A study on mechanical and pressure-sensitive properties of cement mortar with nanophase materials , 2004 .

[21]  S. H. Alsayed,et al.  Hybrid effect of carbon nanotube and nano-clay on physico-mechanical properties of cement mortar , 2011 .