大坍落度混凝土流动性质的表征方法——从水泥浆的流动性到混凝土的流变性能  

Characterization Method of Flow Properties of Large Slump Concrete—— From the Fluidity of Cement Slurry to the Rheological Properties of Concrete

作　　者：刘自强 

机构地区：[1]景磐城建混凝土有限公司

出　　处：《混凝土世界》2020年第2期44-52,共9页China Concrete

摘　　要：混凝土坍落度是坍落度桶内的拌合物截锥体去除周围约束后,在自重作用下发生变形大小的度量。拌合物自重所具有的势能在坍落过程中一部分转变成向下运动的动能,另一部分转变成克服拌合物内部粒子间作用力而产生的变形能,以及拌合物在底板上铺展时需要克服底板材料中的分子对拌合物分子间的相互作用能。按照拌合物变形的大小,分别讨论了截锥体小变形和截锥体铺展两种情况下的能量转换方式,并在考虑粒子间相互作用力与拌合物与底板接触角两个因素的情况下对宾汉姆流体方程进行了修正,以期对大坍落度混凝土拌合物的流变方程进行量化分析。The slump of concrete is a measure of the deformation size under the action of self-weight after the mixture cone in the slump bucket removes the surrounding constraints. The potential energy of the self-weight of the mixture is converted into the kinetic energy of the downward movement during the process of the slump, and the other part is transformed into the deformation energy generated by the interaction between the particles inside the mixture, and the mixture is spread on the bottom plate. There is a need to overcome the interaction energy between the molecules in the substrate material and the molecules of the mixture. According to the deformation of the mixture, the energy conversion modes of the small deformation of the frustum and the frustum spreading are discussed respectively, and the two factors of the interaction force between the particles and the contact angle between the mixture and the bottom plate are considered. The Bingham fluid equation was modified to quantify the rheological equation of the large slump concrete mix.

关 键 词：大坍落度混凝土 流动性质 粒子间相互作用力 表面张力 接触角 

分 类 号：TU528[建筑科学—建筑技术科学]