When added to cement, starch may exhibit very good viscosity and water retention, without delaying the set. Therefore, it can be used to develop self-levelling concrete which consolidates homogeneously under its own weight without any vibration. Starch is mixed with a superplasticizer and replaces Welan gum as viscosity agent. This paper presents the influence of starch on the properties of self-levelling concrete : flow, bleeding, segregation, and strength. Reduced bleeding and segregation were observed as the starch content (dry matter) was 1‰ of the cement content and the superplasticizer in the range of 4 to 5 kg/m~3. The interactions between starch and cement were investigated by means of conductivity, solution analysis and environmental scanning electron microscopy. The morphology of hydrates was modified by the presence of starch, after 16 hours of hydration.
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