کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
257295 | 503584 | 2014 | 10 صفحه PDF | دانلود رایگان |
• We studied composite binders of hemihydrate or anhydrite and blast-furnace slag.
• The main hydration products are gypsum, amorphous C–S–H and ettringite.
• Gypsum from anhydrite is less porous than the gypsum matrix from the hemihydrate.
• Excellent dimensional stability is observed when silica fume and fly ash are used.
• C–S–H with Ca/Si composition from 1.08 to 1.78 was intimately mixed with the gypsum.
This paper presents results of an investigation of calcium sulphate-blast furnace slag binders cured for up to 600 days with small additions of fly-ash or silica fume. Hemihydrate and fluorgypsum were used as the calcium sulphate sources. The binders showed good mechanical and hydraulic properties; the water resistance was attributed to the formation of C–S–H with Ca/Si ratio between 1.08 and 1.78 finely intermixed with the gypsum initially formed. Ettringite was formed after the reaction between gypsum and aluminum from the slag and fly ash; however, its formation was hindered in the presence of silica fume, which improved the dimensional stability.
Journal: Construction and Building Materials - Volume 71, 30 November 2014, Pages 317–326