Compressive strength, water absorption, water sorptivity and surface radon exhalation rate of silica fume and fly ash based mortar

• Published in: Journal of Building Engineering 2019-05, Vol.23, p.369-376
• Main Authors: Hatungimana, Daniel, Taşköprü, Caner, İçhedef, Mutlu, Saç, Müslim Murat, Yazıcı, Şemsi
• Format: Article
• Language: English
• Subjects: Limestone fine aggregate; Radon transport; Sealed can technique; Volume of permeable pore
• ISSN: 2352-7102; 2352-7102
• DOI: 10.1016/j.jobe.2019.01.011

In this study, the effect of partial cement replacement with silica fume and fly ash on the compressive strength, water absorption, volume of permeable pore, water sorptivity, radon content and surface radon exhalation rate of mortar mixtures were investigated. It was observed that the compressive strength of mortar mixtures containing silica fume as partial cement replacement increased as the amount of silica fume content increased while the water absorption, volume of permeable pore, water sorptivity and radon exhalation rate of mortar mixtures decreased. The decrease in surface radon exhalation rate was ranged between 23% and 43% while that of mortar mixtures containing fly ash increased up to 15% of the rate of the control mortar mixture. Results showed that silica fume addition decreased the radon concentration and surface radon exhalation rate while fly ash showed a detrimental effect. •The water absorption, volume of permeable pore and sorptivity of mortar mixtures decreased as the amount of silica fume increased.•On the other hand, mortar mixtures containing fly ash as cement replacement exhibited a low compressive strength, high water absorption and sorptivity compared to control mortar.•The radon exhalation rate of mortars containing fly ash was increased up to 15% of the rate of control mortar.•The decrease in radon concentration of mixtures containing silica fume as cement replacement may also be explained by the low radium-226 concentration of silica fume comparing to that of other mortar ingredients.•The use of silica fume as cement replacement showed good performance than the use of fly ash in compressive strength, water absorption, volume of permeable pore, water sorptivity and surface radon exhalation rate viewpoints.