若干因素对水泥砂浆流变性能的影响

Influence of Several Factors on Rheological Properties of Cement Mortar

采用旋转黏度计研究了不同因素对水泥砂浆流变性能的影响,分析了水泥砂浆的塑性黏度、屈服应力及触变性与流动度之间的关系.结果表明:当流动度为134~300mm时,水泥砂浆的流变特征符合宾汉姆流体模型;水灰比、骨胶比、矿物掺和料以及化学外加剂等因素虽对水泥砂浆的塑性黏度、屈服应力及触变性有不同程度的影响,但并不改变水泥砂浆的流体模型;水泥砂浆的塑性黏度、屈服应力与流动度之间的相关性较弱,而水泥砂浆的触变性与流动度之间存在相关性.

Influence of different factors on rheological properties of cement mortar was investigated using rotational viscometer,and the relationships between the plastic viscosity,yield stress,thixotropy and fluidity of cement mortar were studied.The results show that when the fluidity is 134300mm,the rheological characteristic of cement mortar conforms to Bingham model.Although the factors of water-cement ratio,aggregate-cement ratio,mineral admixtures,and chemical admixtures have different effects on plastic viscosity,yield stress,and thixotropy of cement mortar,they do not change the rheological model of cement mortar.The correlation between plastic viscosity,yield stress and fluidity of cement mortar is weak,but there is a correlation between thixotropy and fluidity of cement mortar.