Effect of Curing Temperature on Low Cement Castable Setting Retardation Mechanism

摘要

The setting time of low cement castable is drastically changed by curing temperature. In particular, castable working above 30°C strongly demands retarder additives in order to retain working time; Boric acid has widely been used for this purpose. A recent paper has reported that the castable setting retardation mechanism achieved by boric acid addition is caused by a selective permeation ability of gel precipitate formed on the surface of alumina cement. However the effect of curing temperature on the retardation mechanism has not been reported.The purpose of this research is to clarify the effect of curing temperature on the retardation mechanism of the addition of boric acid on castable setting.