Micro-structural Examination of The Effect of Sulfate on Cement Mortars with Blast Furnace Slag Substitution

Year 2018, Volume: 2 Issue: 1, 8 - 18, 30.06.2018

Özer Sevim

Abstract

Sulfate is a major chemical threat to concrete and reinforced
concrete structures. In this study, a micro-structural analysis of the effects
of sulfate on cement mortars with blast furnace slag substitution was
conducted. To observe the effect of blast furnace slag on cement mortar, blast
furnace slag substitution was made instead of CEM I 42.5 R cement at different
ratios. Micro-structures of samples cured in potable water and 10% Na2SO4
solution for 2, 7, 28, 90 days were analyzed. A comparative chemical analysis
of the samples, C-S-H (Calcium Silicate Hydrate), CH (Calcium Hydroxide) and
Ettringite developments were presented. As a result, it was observed that CH
gels develop in 7 day samples, C-S-H gels in 28 day samples, and ettringite in
samples cured in % 10 Na2SO4 solution for 90 days. 

Keywords

Micro-structure, Blast-furnace slag, Sulfate effect, Cement mortar

Micro-structural Examination of The Effect of Sulfate on Cement Mortars with Blast Furnace Slag Substitution

Abstract

Sulfate is a major chemical threat to concrete and reinforced concrete structures. In this study, a micro-structural analysis of the effects of sulfate on cement mortars with blast furnace slag substitution was conducted. To observe the effect of blast furnace slag on cement mortar, blast furnace slag substitution was made instead of CEM I 42.5 R cement at different ratios. Micro-structures of samples cured in potable water and 10% Na2SO4 solution for 2, 7, 28, 90 days were analyzed. A comparative chemical analysis of the samples, C-S-H (Calcium Silicate Hydrate), CH (Calcium Hydroxide) and Ettringite developments were presented. As a result, it was observed that CH gels develop in 7 day samples, C-S-H gels in 28 day samples, and ettringite in samples cured in % 10 Na2SO4 solution for 90 days. 

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