水泥-石灰石粉浆体流变经时行为研究

Time-Dependent Behavior of Rheology for Cement-Ground Limestone Paste

研究了水泥-石灰石粉浆体流变参数随水化时间的变化,采取RHEORIAB QC型旋转黏度计测定水泥-石灰石粉浆体流变,采用Herschel-Bulkley模型拟合浆体曲线得到相关流变参数,分别利用Roussel和Philippe提出的模型对水泥-石灰石粉浆体的动态屈服应力和稠度进行拟合。结果表明:水泥浆体动态屈服应力比石灰石粉浆体小,稠度比石灰石粉浆体大;水泥-石灰石粉浆体动态屈服应力、稠度随水化时间线性增大,随石灰石粉掺量增加,增大速率线性减小,其初始动态屈服应力线性增大,初始稠度按二次抛物线先增大后减小。

The variation of rheological parameters with hydration time for the cement-ground limestone paste was studied and the rheology of cement-ground limestone paste was measured through the rotational viscometer of RHEORIAB QC type,the related rheological parameters was obtained by fitting paste rheological curve based on Herschel-Bulkley model. Dynamic yield stress and consistence of cementground limestone paste were fitted respectively by models proposed by Roussel and Philippe. The results show that the dynamic yield stress of cement paste is smaller than ground limestone paste,while the consistency is larger. The dynamic yield stress and consistency of cement-ground limestone paste linearly increase with hydration time; the increasing rate of the dynamic yield stress and consistency linearly decrease with the increasing mixing amount of ground limestone,and the initial dynamic yield stress linearly increase, while the consistency increases at first then decreases and presents a quadratic parabolic law.