| 摘要 |
PURPOSE:To reduce the amt. of an expensive water-reducing agent added by adding citric acid or sodium citrate and a defoaming agent to the above material contg. the water-reducing agent having high performance such as a condensation product of alkylallylsulfonate. CONSTITUTION:0.01-0.1wt.% condensation product of alkylallylsulfonate and/or condensation product of ligninsulfonate as a water-reducing agent having high performance, 0.05-0.2wt.% one or more among citric acid, oxalic acid, tartaric acid, sodium citrate and potassium sodium tartarate and 0.005-0.05wt.% defoaming agent are added to 100wt.%, in total, of 60-80wt.% refractory aggregate and 20-40wt.% Portland cement to obtain a refractory concrete material. By adding citric acid, etc., to the water-reducing agent, air entraining action is accelerated and flowability is improved, so the amt. of the water-reducing agent added can be remarkably reduced. Since excess air entraining action makes concrete porous and reduces the strength, the defoaming agent is added. |
