| 摘要 |
PURPOSE:To place homogeneous concrete requiring no compaction to a high- density bar-arranging section, etc., even in a low slump by using concrete mix, in which a part of aggregate is replaced with stone dust and to which a dispersing agent, etc., are blended. CONSTITUTION:Parts of fine aggregate and coarse aggregate are replaced with stone dust of 150-330kg/m<3> and a dispersing agent is compounded and kneaded within a range of unit water quantity: 160-180kg/m<3> and a water-cement ratio:30-70%, thus manufacturing concrete mix having a slump flow value of 50-70cm. Wahlen gum having loadings of 30-300g/m<3> is mixed and blended previously in the concrete mix together with stone dust, etc. Stone dust blended having mean grain size of 15mum or less is used, and a substance, in which a beta-naphtha-lene sulfonic acid/formalin condensate is compounded with an alkali- soluble reactive high molecule, is employed as the dispersing agent. Accordingly, concrete mix kneaded is cast excellently by its own weight without clearances and tight-bypacked even in a high-density bar-arranging section, etc. |
