铁尾矿砂水泥基灌浆料力学性能影响因素实验研究

Experimental study of influence factors on the mechanical property of iron tailings sand cement-based grouting material

以抗折强度和抗压强度作为考核指标,重点研究了铁尾矿砂替代率、灌浆料水灰比以及灰砂比对铁尾矿砂水泥基灌浆料力学性能的影响规律,并通过扫描电子显微镜对硬化浆体进行微观结构分析。试验结果表明:灌浆料胶砂强度遵循骨料最紧密堆积理论,即混合砂堆积密度愈大,胶砂强度愈高;灌浆料各龄期抗压强度随水灰比的增大均呈抛物线规律变化,其最大点位于水灰比为0.29处;各龄期抗折强度与抗压强度则随灰砂比减小出现"钟形分布"的发展趋势,灰砂比值为0.9时,抗压强度最高。

The flexural strength and compressive strength were used as the evaluation index.The factors which substitution rate of iron tailings sand, water-cement ratio and cement-sand ratio effect on the mechanical property of the cement-based grouting material were stud- ied.Then the microscopic structure was analyzed by the scanning electron microscope （SEM）.The experimental result shows that the mortar strength of grouting material followed the aggregate of closest packing theory, and the larger the bulk density of mixed sand was, the higher the mortar strength of grouting material.The compressive strength of grouting material varied parabolically in each age as the water-cement ratio increase.The maximum compressive strength of each age was gotten when the water-cement ratio was 0.29.With the ce- ment-sand ratio decrease,the trend of flexural and compressive strength graph was a bell-shape in the distribution curve figure.When the cement-sand ratio was 0.9, the compressive strength reached the highest value.