Influence of Chemical Admixtures and Mixing on the Mix Proportion of General Purpose Self-Compacting Concrete

摘要

In this paper, the infleunces of the chemical admixtures and the mixing intensity on the mixture proportioning of gneeral purpose Self-Compacting Concrete (SCC), as a internal and a external giverning factor respectively, were tried to be understood qualitatively. From the experiemtnal resutls, it was found that the adequate value of the water to powder volume ratio (V_w/V_p) was varied due to the type of superplasticizer applied. The polycarboxylate type of superplasticizer used made the mortars less viscous than the melamine sulfonate and/or naphtnalene sulfonate type of superplasticizer used when W_w/V_p due to its characteristics to make the mixture viscous. Moreover, it was also clarified that the adequate V_w/V_p was strongly influenced by the mixer type and the mixing time. It could be found in a different value for each mixing way even though the same materials were used. this phenomena was tried to be explained by the three effects of mixing efficinecy on the property of the paste phase in fresh concrete.