AGGREGATE FOR CONCRETE AND METHOD FOR REMOVING EXCESS WATER IN SETTING OF CONCRETE USING SAID AGGREGATE

摘要

PURPOSE:To provide the title aggregate for concrete capable of developing strength and capable of removing excess water by forming a protective film consisting of the polymer to be disintegrated by the hydrolysis in water or an aq. alkaline soln. on the surface of a dried aggregate. CONSTITUTION:The protective film consisting of a polymer (e.g., polylactic acid and polyglycolic acid) to be disintegrated by the hydrolysis in water or an aq. alkaline soln. is previously formed on the surface of the dried aggregate for concrete. The dried aggregate having the protective film is used as a part or the whole of the aggregate, and mixed with cement, water, etc. The cement is set at a placing position. In the process of the setting at the placing position, the excess of water over the water amt. to be used in the hydration of cement is used for the disintegration of the protective film and absorbed by the dried aggregate, and the excess water can be removed.