水泥细度和外加剂对水泥浆流动性能的影响  

Effects of cement fineness and admixtures on the flowability of cement paste

作　　者：胡泊枫 王水山 王雨利[1] 贺航[1] HU Bofeng;WANG Shuishan;WANG Yuli;HE Hang(School of Materials Science and Engineering,Henan Polytechnic University,Jiaozuo 454003,China;College of Textile and Clothing Engineering,Soochow University,Suzhou 215006,China)

机构地区：[1]河南理工大学材料科学与工程学院,河南焦作454003 [2]苏州大学纺织与服装工程学院,江苏苏州215006

出　　处：《混凝土》2024年第8期83-89,共7页Concrete

基　　金：国家自然科学基金(51678220)。

摘　　要：为了探究原材料的性能特点及外加剂对混凝土流动性能的影响,以水泥浆为研究对象,通过硅酸盐水泥细度、减水剂和增稠剂等对水泥浆中的填充水、吸附水和自由水的影响,分析了它们对水泥浆体流动性能的影响。试验结果表明:随着水泥颗粒粒径减小,填充水和吸附水呈现增大的趋势,但自由水量与流动度之间的线性关系表明,超细硅酸盐水泥浆体流动对随自由水量的增加幅度是大于普通硅酸盐水泥的,这说明水泥的细度对浆体流动性能的影响主要在用水量较小时,即水灰比较小时。无论是萘系减水剂还是聚羧酸减水剂,随着减水剂掺量的增加,填充水和吸附水均呈减小的趋势,流动度随自由水量增加增大的幅度逐渐增大。羧甲基纤维素(CMC)和羟丙基甲基纤维素(HPMC)均使填充水增大,在一定掺量范围内对吸附水基本上没有影响,但超过某一掺量时,均使吸附水大幅增加;CMC对流动度与自由水之间的线性关系影响不大,HPMC使流动度随自由水的增加幅度呈减小的趋势。这对探究原材料的性能特点和外加剂等对混凝土流动性的影响,具有较好的参考价值。In order to investigate the influence of the performance characteristics of raw materials and admixtures on the flowability of concrete,cement paste was used as the object of study,and their effects on the flowability of cement paste were analyzed through the effects of Portland cement fineness,water reducing agents and thickening agents on the filling water,adsorbed water and free water in cement paste.The test results show that as the particle size of cement decreases,the filling water and adsorbed water show an increasing trend,but the linear relationship between the free water and the flowability shows that the flowability of ultrafine Portland cement paste increases more with the free water than that of ordinary Portland cement,which indicates that the effect of the fineness of cement on the flowability of the cement paste is mainly when the water consumption is smaller,that is,when the water-cement ratio is smaller.Whether it is naphthalene-based superplasticizer or polycarboxylate superplasticizer,as they increase,both filling water and adsorption water decrease gradually,while the flowability gradually increases with the increase of free water.Both carboxymethyl cellulose(CMC)and hydroxypropyl methyl cellulose(HPMC)increase the filling water,and basically have no effect on the adsorption water within a certain dosing range,but both make the adsorption water increase significantly when exceeding a certain dosing.CMC had little effect on the linear relationship between flowability and free water,and HPMC caused a decreasing trend of flowability with the increase of free water.This is a good reference for exploring the influence of performance characteristics on the flowability of concrete,such as raw materials and admixtures etc.

关 键 词：硅酸盐水泥 细度 流动度 减水剂 增稠剂 

分 类 号：TU528.042[建筑科学—建筑技术科学]