To obtain a concrete board for a formwork and its manufacture, comprising a two-directional chemical prestressed concrete plate capable of maintaining prestress effectively even for several months after the concrete board is manufactured.
Concrete boards for a formwork, which are used for formworks for forming concrete structures and which are not removed even after concrete cast into the inside of the formworks has set, are produced by a manufacture wherein high-expansive concrete, in which a lime-based expanding material is blended with cement at the rate of substitution of at least 10%, preferably 10-30%, more preferably 15-30%, based on the amount of unit cement, is cast into a form for molding, in which reinforcing materials are disposed in two directions.
YAMADA KAZUO
GO SHIYOUNEI
TSURUTA TAKESHI
CHICHIBU ONODA CEMENT CORP
ORIENTAL CONSTR CO LTD
Fukuda Takemichi (2 outside)
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