摘要
建立了侧面滑移模型,并推导出水泥浆体剪切应力和剪切速率的计算公式。将公式应用到水泥浆体扩展度的动态变化过程,获得浆体扩展度随时间线性变化阶段的“剪切应力-剪切速率”曲线,求得不同水灰比水泥浆体的塑性粘度和屈服应力,并与旋转粘度计的测量值进行了比较。结果表明,随时间延长,水泥浆体扩展速率表现出先慢后快再变慢的特点,并存在快速变化的线性段。扩展度快速变化线性段的塑性粘度与屈服应力经比例系数修正后与旋转粘度计测定值吻合良好。由此说明,对最终扩展度在一定范围(180~320 mm)的水泥浆体,可以通过扩展度动态测量表征浆体的流变参数。
The side slip model was established,and the formulae for calculating shear stress and shear rate of cement paste were derived.The formulae were applied to the dynamic change process of slump flow of cement paste,and the"shear stress-shear rate"curves of the time-dependent linear stage were obtained.So the plastic viscosity and yield stress of cement paste with different water cement ratios were obtained and compared with the measured value by a rotary viscometer.The results show that with the increase of time,slump flow rate of cement paste shows the characteristics of first slow,then fast and slow at last,and there is a fast-changing linear segment.The plastic viscosity and the yield stress of fast-changing linear segment revised by proportional coefficient are in good agreement with the measured value by the rotary viscometer.It shows that the rheological parameters of cement paste with the final slump flow of 180-320 mm can be characterized by dynamic measurement of slump flow.
作者
伍勇华
党梓轩
祝婷
李莹
何娟
WU Yonghua;DANG Zixuan;ZHU Ting;LI Ying;HE Juan(College of Materials Science and Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)
出处
《硅酸盐通报》
CAS
北大核心
2020年第9期2732-2738,2744,共8页
Bulletin of the Chinese Ceramic Society
基金
陕西省社会发展科技攻关项目(2016SF-443)。
关键词
水泥浆体
扩展度
剪切应力
剪切速率
塑性粘度
动态测量
cement paste
slump flow
shear stress
shear rate
plastic viscosity
dynamic measurement