摘要
考虑纳米偏高岭土(NMK)质量分数(0、1%、3%、5%、10%)、减水剂(SP)、水胶质量比(0.40、0.45、0.50)等影响因素,研究了新拌NMK水泥浆颗粒水膜厚度与流变参数的关系.基于标准稠度用水量法和最大颗粒浓度法获得颗粒堆积密度;利用颗粒堆积密度和颗粒比表面积得到水泥浆颗粒水膜厚度;NMK水泥浆流变参数由流变仪测得;并通过泌水性试验测定NMK水泥浆泌水率.研究结果表明:NMK导致水泥浆颗粒堆积密度、水膜厚度减小;水泥浆颗粒水膜厚度随水胶比的增加而增大;减水剂导致NMK水泥浆颗粒堆积密度和水膜厚度增大;NMK使水泥浆泌水率显著降低.基于试验结果,提出一种利用水膜厚度预测水泥浆流变参数(流动度、屈服应力、触变性等)的数学模型,并利用国内外相关试验资料验证了模型的有效性,从而为NMK水泥浆流变参数预测提供了科学的理论依据和参考.
The effects of nano-metakaolin(NMK)mass fraction(0,1%,3%,5%,10%),superplasticizer(SP),and water to binder ratio(0.40,0.45,0.50)were taken into consideration,and the relationship between the water film thickness(WFT)and rheological parameters of fresh NMK cement paste particles was investigated.The standard consistency water consumption and maximum particle concentration methods were applied to obtain the particle packing density,respectively.The WFT of cement paste particles was calculated by the particle packing density and total specific surface area.The rheological parameters of NMK cement pastes were measured by a rheometer.The bleeding rate of NMK cement pastes was determined by the bleeding test.The results show that NMK leads to a decrease in the packing density and WFT,while the WFT of cement paste particles increases with the increase of the water to binder ratio.It is observed that the packing density and WFT of NMK cement paste increase with SP addition,and the bleeding rate of cement paste decreases significantly with NMK addition.Based on the experimental results,a mathematical model is proposed to predict the rheological parameters(fluidity,yield stress,thixotropy,etc.)of cement paste by the WFT.In addition,the prediction model is verified by the experimental data listed in the literature.Therefore,the proposed model can provide a scientific theoretical basis and reference for predicting the rheological parameters of NMK cement pastes.
作者
李秋超
范颖芳
李学良
Li Qiuchao;Fan Yingfang;Li Xueliang(Department of Civil Engineering,Dalian Maritime University,Dalian 116026,China)
出处
《东南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2022年第2期273-281,共9页
Journal of Southeast University：Natural Science Edition
基金
国家自然科学基金资助项目(51578099)。
关键词
水膜厚度
流变参数
纳米偏高岭土
水泥浆
数学模型
相关性
water film thickness
rheological parameters
nano-metakaolin
cement paste
mathematical model
correlation
作者简介
李秋超(1995—),男,博士生;联系人:范颖芳,女,博士,教授,博士生导师,fanyf@dlmu.edu.cn。
