METHOD OF PRODUCING CONCRETE

摘要

A fine aggregate is stored in a high storage silo and its surface water content is so controlled that its variation may be kept within ?1% by weight. The fine aggregate, cement and primary water containing an air entraining agent are mixed in an upper mixer (primary mixing) to prepare mortar. The mortar, a coarse aggregate and secondary water containing a water reducing agent are mixed in a lower mixer (secondary mixing) to produce mixed concrete.