Influence of class F fly ash and silica nano-micro powder on water permeability and thermal properties of high performance cementitious composites

• Main Author: Jalal Mostafa
• Format: Article
• Language: English
• Published: De Gruyter 2013-02-01
• Series: Science and Engineering of Composite Materials
• Subjects: capillary absorption; cementitious composites; high performance concrete (hpc); silica nano-micro powder; tga; water absorption
• Online Access: https://doi.org/10.1515/secm-2012-0054

This paper investigates the influence of class F fly ash and silica nano-micro powder on water permeability and thermal properties of high performance concrete (HPC) as one of the most important cementitious composites. For this purpose, a fraction of Portland cement was replaced by silica fume, silica nanoparticles, blend of silica fume and silica nanoparticles and three percentages of fly ash as 10%, 2%, 10+2% and 5%, 10%, 15%, respectively. Specimens were prepared with two binder contents as 400 and 500 kg/m3. Thermal properties were investigated via thermogravimetric analysis (TGA). Capillary water absorption tests of the specimens were carried out at the age of 90 days. The results showed that the pozzolanic admixtures especially blend of silica fume and SiO2 nanoparticles have a significant effect on thermal properties and particularly capillary water absorption.