Construction of self compacting and self leveling concrete in complicated structure. Fukuzatsuna keijo kutai wo seko (Kawasaki Tokuyama Namakon kotsuzai setsubiyo kiso koji)

Super workable concrete with self-compacting and self-leveling was applied to the concrete work of hopper of aggregate silo with complicated structure. The proportion of this concrete is characterized by the less amount of hinder comparing with the conventional self-placable concrete. Acrylic type thickener was used to improve the fluidity and material segregation resistance property. A horizontal forced double-axle mixer (capacity, 3 cubic meter) was used for preparation of the concrete. Slump flow of the fresh concrete decreased linearly up to 60 minutes, and decreased by about 10cm for 120 minutes. The compressive strength of hardened concrete was 200 kgf/cm[sup 2] at the age of 7 days, and 530 kgf/cm[sup 2] at the age of 91 days. From correlations between the slump flow, air content, water-cement ratio, and the compressive strength, it was found that the compressive strength decreases with increasing the slump flow. Rationalization and laborsaving of the super workable concrete works were confirmed. 1 ref., 10 figs., 4 tabs.