不同水灰比、砂灰比下碳酸钙晶须对水泥砂浆流变性的影响  

Influence of Calcium Carbonate Whisker on Rheology of Cement Mortar with Different Water–Cement Ratios and Sand–Cement Ratios

作　　者：曹明莉[1] 许玲[1] 张聪[1] 

机构地区：[1]大连理工大学土木工程学院,辽宁大连116024

出　　处：《硅酸盐学报》2016年第2期246-252,共7页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金项目(51478082)

摘　　要：采用旋转流变仪研究碳酸钙晶须增强水泥砂浆拌合物的流变性能。分析不同水灰比、砂灰比及碳酸钙晶须掺量下,新拌砂浆的屈服应力、塑性黏度和滞回环面积的变化。结果表明:碳酸钙晶须增强水泥砂浆拌合物的流变性符合Bingham模型;水灰比从0.35减小至0.30时,新拌碳酸钙晶须水泥砂浆的屈服应力、塑性黏度均增大,最大增幅分别为92.0倍和4.8倍;碳酸钙晶须掺量从0增大至2.5%时,新拌碳酸钙晶须水泥砂浆的屈服应力、塑性黏度均呈增大趋势,最大增幅分别为24.5倍和1.6倍。分析滞回环面积的变化表明,随着水灰比的减少和晶须掺量的增加,浆体内部阻碍流动的絮凝结构和网状结构的数量增大,这也是导致拌合物流动性差、流变参数大的主要原因。The rheological properties of fresh calcium carbonate whisker reinforced cement mortar were determined using rotational rheometer. The yield stress, plastic viscosity and the area of hysteresis loop of fresh mortars at different water--cement ratios, sand---cement ratios and calcium carbonate whisker content were analyzed. The results indicate that the fresh calcium carbonate cement mortar mixtures follow the Bingham model. The yield stress and plastic viscosity increase with decreasing water--cement ratio from 0.35 to 0.30, resulting in the maximum increased amplifications of 92.0 and 4.8 times, respectively. The yield stress and plastic viscosity increase with increasing the content of calcium carbonate whisker from 0 to 2.5%, leading to the maximum increased amplifications of 24.5 and 1.6 times, respectively. The analysis of the hysteresis loop area shows that the quantity of flocculation and reticulation structures increase with the decrease of water---cement ratio and the increase of calcium carbonate whisker amount, leading to the poor fluidity and high rheological parameters of the mixtures.

关 键 词：流变性 碳酸钙晶须 屈服应力 塑性黏度 滞回环 

分 类 号：TB332[一般工业技术—材料科学与工程]