中文摘要：

新拌的水泥基材料是典型的屈服应力流体,由不同粒径的固体颗粒形成的悬浮液组成,其固体颗粒的范围从亚微米级到厘米级。当受到剪切作用时流体内部存在两种相反的作用,分别会导致流体发生剪切稀化和剪切增稠,流体的流变特性由二者共同决定。本文对新拌水泥基材料的流变机理、模型以及流变仪测量方面的研究进展进行了综述,对具有代表性的流变模型,包括Bingham模型、Modified Bingham模型和Herschel-Bulkley模型等的特点、适用条件等进行了分类总结。影响流变特性的主要因素是固体颗粒体积分数和剪切速率,当剪切速率与剪切应力之间存在非线性关系时,难以根据流变仪的测量数据建立流变方程。本文中讨论了一些建立模型的新方法,通过计算流体力学和离散元理论相结合可以较好地模拟水泥基材料流变特性。

英文摘要：

Fresh cementitious materials are a typical yield stress fluid. It is composed of many solid particles with different sizes, which the size distribution is from a few sub-microns to several centimeters. When it is sheared, the fluid endures two opposite effects, which can lead to shear thinning and shear thickening, respectively. The rheological properties of the fluid are determined jointly by these two effects. The rheological mechanisms, models, and some measurement issues were summarized. Several typical rheological models, including the Bingham model, the modified Bingham model and the Herschel-Bulkley model, etc. were discussed The features, conditions and ranges of models were classified and summarized. The volume fraction of solid particles and shear rate are the two main factors for rheological models. However, when a nonlinear relationship between shear stress and shear rate exists, sometimes it is difficult to build the rheological models based on the observed data. Some new modeling methods were discussed. In the field of computational simulation, the combination of computational fluid dynamics with discrete element method can be applied to simulate the rheological properties of cementitious materials more precisely.