| Alkali-activated slag concrete is a kind of new construction marerial.Compared to traditional portland cement concrete, it have the property of high strength,excellent durability, energy saving,making the best use of industry waste protecting ecology system.so it is a new material with broad developing future. It is accord with the development of the society and economy.In this paper, the actuality of study on sulfate attack of alkali-activated slag concrete was summarized.The characters of sulfate attack of alkali-activated slag concrete at normal temperature and low temperature were studied. It is acknoeledged that:①AFT appears in the alkali-activated slag concrete immerged to 5% MgSO4 solution.It can increase the strength and weight of the concrete. The AFT will be more as the solution to slag quantity ratio increase. It can reduce the AFT by adding 5%10% silica fume.②Gypsum appears in all the alkali-activated slag concretes immerged to 5% (NH4)2SO4 solution.The attack extent and speed of MgSO4 solution is higher than Na2SO4 solution at the same concentration.③From -5℃to 25℃,no thamasite occur in the alkali-activated slag concrete with 10% limestone immerged to 5% Na2SO4 solution.④Besides AFT, Thaumasite appeares in the alkali-activated slag concrete with 10% limestone immerged to 5% MgSO4 solution at -5℃and 5℃after 180 days.It makes out that The sulfate attack of TSA appears at low temperature.⑤Thaumasite only appears in the alkali-activated slag concrete containing AFT,It makes out that in 180 days, Thaumasite only transform from AFT,but not C-S-H directly.
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