Cement and Concrete Research ( IF 11.4 ) Pub Date : 2021-07-01 , DOI: 10.1016/j.cemconres.2021.106530 Shirin Fataei , Egor Secrieru , Viktor Mechtcherine , Nicolas Roussel
For the first time, a first-order physical correlation between pumping parameters (pressure and flow rate), granular skeleton properties (particle diameter and packing properties) and LL properties (thickness and viscosity) is proposed. This correlation is derived from the analysis of the equations driving shear-induced particle migration in dense suspensions. The model predictions in terms of lubricating layer apparent viscosity are compared to experimental measurements in the case of model concretes prepared with glass beads of various diameters, conventional-vibrated concretes and self-compacting concretes. This comparison is carried out for two flow typologies, namely the Sliper, known for its ability to mimic concrete pumping, and a co-axial tribometer. In all cases, the proposed model is shown to be able to capture qualitatively the observed main features and their evolutions despite the absence of any fitting parameters.
中文翻译:
用于预测混凝土泵送过程中剪切引起的颗粒迁移和润滑层形成的一阶物理模型
首次提出了泵送参数(压力和流量)、颗粒骨架特性(粒径和填充特性)和 LL 特性(厚度和粘度)之间的一阶物理相关性。这种相关性源自对致密悬浮液中驱动剪切诱导粒子迁移的方程的分析。在用不同直径的玻璃珠制备的模型混凝土、常规振动混凝土和自密实混凝土的情况下,将模型预测的润滑层表观粘度与实验测量值进行比较。这种比较是针对两种流动类型进行的,即以模拟混凝土泵送能力而闻名的 Sliper 和同轴摩擦计。在所有情况下,