摘要
采用RHM-3000ICAR流变仪测试了水粉比对粉体-黏度改性剂(VMA)复合型自密实混凝土(简称自密实混凝土)流变行为的影响,比较分析了Bingham模型、Herschel-Bulkley(H-B)模型及改进Bingham模型对该混凝土流变曲线的适用性.结果表明:坍落扩展度与含气量相当的自密实混凝土,随着水粉比的提高,其屈服应力增大,塑性黏度减小;自密实混凝土剪切变稠程度随着水粉比的提高而降低,当水粉比增大至0.40(质量比)时,其剪切变稠现象完全消失,表现出剪切变稀现象;H-B模型和改进Bingham模型均能很好地描述自密实混凝土剪切变形行为,且改进Bingham模型的c/μ对剪切变形的变化更为敏感.
The rheological curves of powder-viscosity modifier admixture( VMA) combination type self-compac- ting concrete(SCC)with different water-powder ratios were determined by means of RHM-3000 ICAR rheom- eter. The data obtained were modeled by the Bingham model, Herschel-Bulkley(H-B) model and modified Bingham model respectively. The results indicate that the yield stress increases with increasing water-powder ratio of the SCC with the same slump-flow and air content, while the opposite is true for the plastic viscosity. The increasing water-powder ratio can weaken the shear thickening behavior. When the water-powder ratio in- creases to 0.40 (by mass), the shear thickening phenomenon completely disappears, showing a shear thinning behavior. Both H-B model and modified Bingham model can describe the shear thickening behavior of SCC, and the c/μ of modified Bingham model is more sensitive to shear deformation.
作者
李化建
黄法礼
程冠之
易忠来
张勇
王振
谢永江
LI Huajian HUANG Fali CHENG Guanzhi YI Zhonglai ZHANG Yong WANG Zhen XIE Yongjiang(Railway Engineering Research Institute, China Academy of Railway Sciences, Beijing 100081, China State Key Laboratory for Track Technology of High-Speed Railway, Beijing 100081, China College of Civil Engineering and Meehanies, Yanshan University, Qinhuangdao 066004, China)
出处
《建筑材料学报》
EI
CAS
CSCD
北大核心
2017年第1期30-35,共6页
Journal of Building Materials
基金
国家自然科学基金资助项目(51378499
51308546)
中国铁路总公司科技开发计划项目(2014G001-C)
关键词
水粉比
自密实混凝土
流变模型
剪切变形
water-powder ratio
self-compacting concrete
rheological model
shear deformation