预拌混凝土中石灰石粉替代粉煤灰的配合比试验研究

Experimental Study on Mix Proportion of Limestone Power Instead of Fly-ash in Pre-mixed Concrete

本文采用勃氏比表面积仪、激光粒度仪及亚基蓝法试验测试并分析了石灰石粉的基本性能。采用江西赣南地区常用工程配合比,研究了石灰石粉替代粉煤灰后对混凝土工作性能和力学性能的影响。结果表明,一定掺量下的石灰石粉,对于不同强度等级的混凝土,通过调整配合比中胶凝材料的组成比例或砂率,优质的石灰石粉可以完全替代混凝土的粉煤灰,石灰石粉混凝土的工作性能更好,其力学性与掺粉煤灰的相当。混凝土的单方成本下降明显,这有利于混凝土企业的降本增效。

In this paper,the basic properties of limestone power was tested by using the Blain specific surface instrument,laser particle sizer and methylene blue method. The effect of limestone powder instead of fly ash on the workability and mechanical properties of concrete was studied by using the mix proportion of common engineering in Jiangxi Gannan area. The results show that the limestone powder under certain dosage can replace the fly-ash completely by adjusting the the sand ratio of concrete and the proportion of the cementitious material for the concrete of different strength grades. The workability of the limestone powder concrete is better,and the mechanical property of the concrete is equivalent to the fly-ash concrete. The cost of one cubic concrete decreases obviously,which is conducive to reducing the cost and increasing efficiency of concrete enterprises.