| 摘要 |
PURPOSE: To obtain a concrete composition excellent in fluidity and packing property, having low strength and excellent in workability by controlling and compounding a starting material composition in a specified range of water to cement ratio and slump flow value. CONSTITUTION: In the concrete composition containing cement, aggregate, water and bentonite, the water to cement ratio (W/C) is set in >=100% and unit water content and bentonite content are set in a slump flow value of 40-50. 70-83wt.% usually used aggregate is compounded per total composition and 5.0-10.0 pts.wt. bentonite is compounded per 100 pts.wt. cement so as to obtain the slump flow value of 40-50. The prepared concrete has a preferably a compression strength after 28day aging of 70-130kgf/cm<2> . |
