New type admixtures were developed for High-fluidity and Super-low shrinkage concretes with water-cement ratio of 40-55%. Properties of fresh and hardened concretes using these admixtures were studied by laboratory test. Properties of these hardened concretes, such as strength and durability were investigated experimentally. Furthermore, effects of reducing and restraining cracks using these admixtures were verified by test on drying shrinkage cracking of restrained concrete. More than 10% drying-shrinkage reduction was obtained for super-low shrinkage concrete using one of these admixtures compared to ordinary concrete. This concrete was applied to a fair-faced wall of a building in Hyogo.

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