硅酸盐学报

新拌水泥浆体絮凝结构与流变行为及有效体积分数的关系

作者：张力冉王栋民潘佳李娟王芳

分类号：TU528.0

出版年,卷(期):页码：2014,42(9):1209-1218

DOI：10.7521/j.issn.0454－5648.2014.09.21

摘要：

在不同水灰比条件下对两种超塑化剂新拌水泥浆体絮凝结构的易变形性、破坏程度、平均大小、解絮及再絮特性与流变行为和有效体积分数的关系进行了研究，通过测定和计算浆体流变参数、触变性(触变环面积)及有效体积分数，表征了浆体絮凝结构的特性。结果表明：浆体流变参数屈服应力τ0反映浆体的变性能力，τ0越小絮凝结构越易变形；浆体触变环面积As越大，絮凝结构的破坏程度越大；浆体的剪切稀化、剪切稠化行为可表征解絮与再絮程度；有效体积分数越大，絮凝结构平均尺寸越大。

The relationship between flocculent structures and rheological behaviors/effective volume fraction of fresh cement paste with two types of superplasticizers was investigated. The deformability, broken degree, average size, deflocculation and reflocculation of flocculent structures at different water/cement ratios were discussed. The properties of flocculent structures with respect to the rheological parameters, area of thixotropic loop and effective volume fraction were characterized. The results indicate that the smaller yield stress τ0 is, the worse flocculent structure will be. The broken degree of flocculent structures increases when the areas of thixotropic loop As increases. The degrees of deflocculation and reflocculation were determined according to the shear－thinning and shear－thickening behavior of the pastes. It is also indicated that the average size of flocculent structure increases when the effective volume fraction increases.

基金项目：

基金项目：国家自然基金面上项目(50872151)；中国矿业大学(北京)博士研究生拔尖创新人才培育基金(00－800015Z637)；中国矿业大学(北京) 2013年国家级大学生创业实践项目资助。

作者简介：

第一作者：张力冉(1986—)，女，博士研究生。通信作者：王栋民(1965—)，男，教授。

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