POROUS CONCRETE AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide inexpensive porous concrete which has a large strength and excellent water penetrability and can easily be produced. SOLUTION: A cement mixture comprising 20 to 60 wt.% of blast furnace slag powder having a specific surface area of 6,000 to 10,000 cm2/g and the remainder of the general Portland cement is prepared. Water is added to the cement mixture to prepare a cement paste which contains the water in an amount of 22 to 40 wt.% based on the binding materials and has a flow value of <=250 mm. The mixture of single grain aggregates having different grain sizes is used as a coarse aggregate. The cement paste is added to the aggregate in an amount of 20 to 60 vol.% based on a space volume in 1 m3 of the bulk volume of the coarse aggregate. The mixture is centrifugally molded at the maximum centrifugal force of 10 to 30 G.