The bulk flow properties of four different fly ashes were assessed at ambient temperature and at 500 °C, using a high temperature annular shear cell. These powders all resulted from industrial processes and had similar chemical compositions but different particle size distributions. Applying a high temperature was found to increase the powder cohesion, with this effect being more significant in the case of the sample with the highest proportion of fines. To better understand the effect of temperature on the bulk flow properties of these materials, a model previously proposed by some of the authors was used to correlate the powder isostatic tensile strength with the interparticle forces and microscale particle contact structure. This model combines the continuum approach with description of particle-to-particle interactions. A comparison with experimental data indicated that the effects of consolidation and temperature on the tensile strength of the fly ashes were correctly described by the model. This theoretical approach also elucidates the mechanism by which the temperature affects the bulk flow properties of fly ashes through modifications of the microscale interparticle contacts.

使用高温环形剪切池在环境温度和500°C下评估了四种不同的粉煤灰的总体流动性能。这些粉末均来自工业过程，具有相似的化学组成，但粒径分布不同。发现施加高温会增加粉末的内聚力，对于细粉比例最高的样品，这种影响更为明显。为了更好地理解温度对这些材料的整体流动性能的影响，一些作者先前提出的模型用于将粉末等静压拉伸强度与颗粒间力和微米级颗粒接触结构相关联。该模型将连续性方法与粒子间相互作用的描述结合在一起。与实验数据的比较表明，该模型正确地描述了固结和温度对粉煤灰抗张强度的影响。这种理论方法还阐明了温度通过改变微粒间接触而影响粉煤灰整体流动性能的机理。