Abstract
A concrete drying shrinkage rate was prescribed for at the AIJ (Architectural Institute of Japan) and the JSCE (Japan Society of Civil Engineers). But, it isn't prescribed for JIS A 5308 as the quality requirement items Because of that, the countermeasure to decrease drying shrinkages wasn't examined in the ready-mixed concrete factory with no shipping experience the construction work of the large metropolitan area in many cases. As one of the guarantee measures concerning the drying shrinkage rate against the purchaser, National Federation ready-mixed concrete industrial association did investigation of actual conditions of the ready-mixed concrete factory in 2008 and 2009 years.
