Title |
Experimental Study on Improving Compressive Strength of MWCNT Reinforced Cementitious Composites
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DOI |
https://doi.org/10.4334/JKCI.2014.26.1.063 |
Keywords |
탄소나노튜브 ; 시멘트 ; 섬유분산 ; 계면활성제 ; 초음파 처리 carbon nanotubes ; cement ; fiber dispersion ; surfactant ; sonication |
Abstract |
This experimental study was intended to improve the compressive strength of multi-walled CNT reinforced cementitious composites with efficiency. The variables considered are the degree of sonication, the amount of surfactant, the replacement ratio of silica fume, etc. Optical microscope informed that fiber dispersion of CNT was improved with the increase of sonication time, and the compressive strength was proved to be enhanced as the degree of sonication increased. When superplasticizer as a surfactant had SP/CNT ratio of 4~6, the best improvement in strength was obtained. Silica fume was shown to produce the highest compressive strength at 10% replacement. Microstructure of CNT composites was also analyzed; XRD and SEM results indicated that CNT addition hardly changed hydration products and microstructure, and MIP analysis found the reduction of total porosity as well as the increase of nano-pores with the size of tens of nm instead of the decrease of pore distribution in the region of around 10 μm and 100 nm. The results of microstructure analysis explains that the strength improvement is closely related to physical contribution rather than chemical influence by adding CNT.
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