Investigation of mechanical and thermal properties of nano SiO2/hydrophobic silica aerogel co‐doped concrete with thermal insulation properties

Lightweight concretes with thermal insulation properties and good compressive strength can be produced by the replacement of normal aggregate of cement mixture with low‐density materials. In this study, sand in a cement mixture has been replaced totally with silica aerogel powder as well as replacement of cement with fly ash. Furthermore, nano silica and silica‐fume were added and incorporated into the concrete matrix. The most obvious finding to emerge from this study was that a lighter sample with no sand contributed to the lowest thermal insulation reduction by 58% of the reference sample and reduction in density to 22.8%, with reduced compressive strength of 27.11 MPa at 28 days. Obtaining of a lighter concrete by using aerogel, a chance of reduced building cooling and heating energy consumption and enhanced indoor comfort with the reduction of mold and condensation on buildings wall was obtained.