Influence of different types of nano-SiO2 particles on properties of high-performance concrete

Khaloo, A ; Sharif University of Technology | 2016

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  1. Type of Document: Article
  2. DOI: 10.1016/j.conbuildmat.2016.03.041
  3. Publisher: Elsevier Ltd , 2016
  4. Abstract:
  5. The aim of this study was to evaluate the effects of applying low replacement ratios (0.75% and 1.50% of the binder weight) of nano-SiO2 particles with different specific surface areas (200 and 380 m2/g) on the properties of high-performance concrete (HPC). Mechanical (compressive and splitting tensile strengths), electrical resistivity, non-destructive (ultrasonic pulse velocity), and microstructural (mercury intrusion porosimetry, X-ray diffraction, and scanning electron microscopy) tests were conducted to investigate the macroscopic and microscopic effects of nano-SiO2 particles on HPC characteristics. The results indicated that the performance of nano-SiO2 particles significantly depended on their specific surface areas and the water to binder (w/b) ratio of the mixtures. By decreasing the HPC w/b ratio from 0.35 to 0.25, nano-SiO2 particles with lower specific surface area performed better than finer one (higher specific surface area). Microstructural investigations demonstrated that the decrease in efficiency of nano-SiO2 particles with higher specific surface area at lower w/b ratio correlates to the formation of nanoparticles agglomerates, particularly at the higher replacement ratio of nanosilica (1.5%). However, the influence on the compressive and splitting tensile strengths and electrical resistivity varied due to differences in performance of nano-SiO2 particles affected the mechanical and durability properties
  6. Keywords:
  7. Electrical resistivity ; Microstructural investigations ; Nano-SiO2 particles ; Non-destructive testing ; Binders ; Bins ; Concretes ; Electric conductivity ; Mechanical properties ; Mercury (metal) ; Nondestructive examination ; Scanning electron microscopy ; Specific surface area ; Tensile strength ; Ultrasonic testing ; X ray diffraction ; Compressive and splitting tensile strengths ; Macroscopic and microscopic ; Mechanical and durability properties ; Mercury intrusion porosimetry ; Microstructural investigation ; Nano- SiO ; Non destructive testing ; Ultrasonic pulse velocity ; High performance concrete
  8. Source: Construction and Building Materials ; Volume 113 , 2016 , Pages 188-201 ; 09500618 (ISSN)
  9. URL: http://www.sciencedirect.com/science/article/pii/S0950061816303270