Investigating the effects of using different types of SiO2 nanoparticles on the mechanical properties of binary blended concrete

Abstract

The aim of this study was to assess the effects of two different types of SiO2 nanoparticles (N and M series) with different ratios on the workability and compressive strength of developed binary blended concretes cured in water and lime solution as two different curing media. N and M series SiO2 nanoparticles with an average size of 15 nm were used as obtained from the suppliers. Fresh and hardened concretes incorporating 0.5%, 1.0%, 1.5% and 2.0% of N and 2% of M series nanoparticles with constant water to binder ratio and aggregate content were made and tested. Fresh mixtures were tested for workability and hardened concretes were tested for compressive strength at 7, 28 and 90 days of curing. Fresh concrete test results showed that the workability of binary blends was reduced in the presence of both types of SiO2 nanoparticles. Hardened concrete test results revealed that the optimal replacement level of cement by N series of SiO2 nanoparticles for producing concrete with considerably improved strength was set at 1.0 wt.% after curing in water. However, the ultimate strengths of binary blended concretes were gained at 2.0 wt.% replacement of cement by both series after curing in lime solution. It is concluded that SiO2 nanoparticles play significant roles in mechanical properties of concrete by formation of additional calcium silicate hydrate gel during treatment, which played an important role in raising highly the compressive strength of binary blends. The current study sheds light on the implications of nanotechnology in nano-engineering of concrete.

Effects of the addition of nanosilica on the rheology, hydration and development of the compressive strength of cement mortars

“…It can be seen that viscosity follows a non-linear trend with respect to nS content and that maximum viscosity values correspond to an intermediate nS content of about 2%, regardless of SP dosage. This result is consistent with the findings of other authors, who reported significant loss of workability in concretes with nS contents of up to 2%[37].The effect of variations in SP dosage on viscosity is more noticeable with higher FA contents, as shown inFigure 3, where an FA content of 12.5% is assumed. In this case, the maximum viscosity values corresponded to the same intermediate nS content of about 2%, but in addition it was observed that increasing SP dosage significantly increased viscosity.…”

Effect of using different types of nano materials on mechanical properties of high strength concrete

“…The improving percentage of compressive strength reaches about 18% with respect to the control mixes. The increase can be due to the fact that calcium hydroxide compounds existing in lime solution react with nanoparticles in their surface areas to form additional C-S-H gel thereby increasing compressive strength [12].…”

Effects of nano-SiO2 particles on the mechanical and microstructural properties of ultra-high performance cementitious composites

“…Using nano-particles can lead to novel properties in concrete. It causes an improvement in the mechanical properties and durability of concrete [6][7][8]. A lot of research has been carried out over the last years in order to understand the influence of nanoparticles on cement and concrete properties [9][10][11][12].…”