Influence on the Performances of Foamed Concrete by Silica Aerogels

Abstract

Aiming at the problems of organic thermal insulation material, SiO 2 aerogel was mixed into foamed concrete in two different ways, to investigate its effects on thermal conductivity, compression strength and volume water absorption of foamed concrete. XRD, FT-IR and SEM have also been used to analyze the relationship between both the amount and the mixing way of aerogel and macro properties of foamed concrete. The results show that directly mixing aerogel into foamed concrete has limited effects on improving its performace, mixing 0.5% of aerogal has little effect on improving thermal conductivity, while mixing 2.5% of aerogel can greatly decrease compression strength though thermal conductivity has been improved. If aerogal has been premixed with glycol and hydroxypropyl methyl cellulose(HPMC) ether and then mixed into foamed concrete, the compression strength will decrease less while thermal conductivity could decrease by 35%, volume water absorption by 31%.