FINE AGGREGATE FOR CONCRETE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide fine aggregate having a prescribed particle diameter distribution required in accordance with the particle size of natural sand to be mixed and provided with constantly uniform quality suitable as the fine aggregate for concrete and a producing method of the fine aggregate for concrete, which is capable of reducing economical load such as the equipment cost or the maintenance cost of a batch type concrete plant. SOLUTION: The fine aggregate 19 for mixed concrete is manufactured by crushing rock or crushed sand with a 1st crusher 3 and sieving with a vibration sieve 5 to prepare 1st fine aggregate raw material sand 17 having a prescribed particle diameter distribution, crushing metallurgical slag lump or metallurgical slag granule with a 2nd crusher 8 and sieving with a vibration sieve 10 to prepare 2nd fine aggregate raw material sand 18 having a prescribed particle diameter distribution and mixing 2 kinds of the fine aggregate raw material sands 17 and 18 to have a prescribed particle diameter distribution in a previously fixed prescribed mixing ratio.