Influence of Minerals and Nanomaterials on the Properties of Reactive Powder Concrete

Abstract

This is an essay in the field of ceramics and composites. Reactive powder concrete was prepared using silica fume, metakaolin and nanomaterials, and then the influence of mineral composition and nanomaterials on the basic characteristics of reactive powder concrete was studied. Silica fume and metakaolin are mixed in fixed proportions, while nano-silica and nano-alumina are mixed in proportions of 0.5%, 1%, 2% and 3% of the cement mass, respectively. The basic characteristics of the modified reactive powder concrete were tested through the density and fluidity experiments of fresh concrete and the strength tests were conducted at different curing ages. The results showed that with the incorporation of nanomaterials, the density of concrete gradually increased, whilethe fluidity continues to decrease; the compressive strength and flexural strength of samples first increase and then decrease with the increase of nanomaterials, and it is concluded that the optimal dosage of nanomaterials is 1%~2%. The high temperature test results show that the compressive strength and flexural strength of reactive powder concrete increase first and then decrease with the temperature, the best temperature is 200 ℃; the rate of strength decrease caused by temperature is CSS>CSA>CMA>CMS. In addition, SEM analysis also shows that high temperature will cause deterioration of the interior of the concrete.

Keywords

• ceramics and composites
• mineral admixtures
• nano materials
• reactive powder concrete
• fluidity
• strength
• high temperature resistance characteristics