减水剂对再生微粉-矿渣-水泥基砂浆流变性能的影响  

Effect of water reducing agent on rheological properties of regenerated micro-powder-slag-cement-based mortar

作　　者：朱涛 马亚鹏 毛明杰[1] 杨秋宁[1] 张东生 ZHU Tao;MA Yapeng;MAO Mingjie;YANG Qiuning;ZHANG Dongsheng(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China;Key Laboratory of the Internet of Water and Digital Water Governance of the Yellow River in Ningxia,Ningxia University,Yinchuan 750021,China;Department of Civil Engineering,KU Leuven,Campus Bruges,Bruges 8200,Belgium)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021 [2]宁夏大学宁夏回族自治区黄河水联网数字治水重点实验室,宁夏银川750021 [3]Department of Civil Engineering,KU Leuven,Campus Bruges,Bruges 8200,Belgium

出　　处：《中国粉体技术》2024年第6期50-61,共12页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:52468068;宁夏回族自治区重点研发计划项目,编号:2021BEG02014。

摘　　要：【目的】探究减水剂对再生微粉-矿渣-水泥基砂浆(regenerated micro-powder-slag-cement-based mortar,RSCM)流变性能的影响,通过添加减水剂有效利用再生微粉和矿渣粉等固废材料,为解决固废基砂浆在工作性能方面的不足提供方案。【方法】使用3种不同减水剂(萘系、三聚氰胺系和聚羧酸系),研究在不同掺量下RSCM流变性能的变化规律,计算RSCM的触变环面积、屈服应力、塑性黏度和水膜层厚度,建立水膜层厚度对于浆体屈服应力的预测模型。【结果】随着减水剂掺量的增加,RSCM的触变环面积、屈服应力和塑性黏度减小,而水膜层厚度增加;三聚氰胺系减水剂对流变性能的改善效果最明显,在三聚氰胺系减水剂质量分数为0.6%时,RSCM的触变环面积为2660 Pa/s,屈服应力达到74.7 Pa、塑性黏度达到2.79 Pa·s,水膜层厚度为0.67μm;若减水剂用量持续增加,RSCM将变得很稀,不能应用于实际工程;RSCM的水膜层厚度与屈服应力呈函数关系。【结论】3种减水剂中,选择三聚氰胺系减水剂是比较合适的;RSCM的水膜层厚度与屈服应力的关系模型具有较高的精度和适用性。Objective In terms of sustainability in civil engineering,a large amount of construction waste is treated to replace cement in order to conserve natural resources and reduce carbon emissions.However,the mortar containing recycled micro-powder and slag powder often shows poor performance.Therefore,when a specific water-binder ratio is maintained,water-reducing agents are often used to improve the performance of slurries containing recycled micro-powder and slag.At present,rheology is considered to be the most effective method to characterize the workability of gellable materials.Hence,the influence of different types of water-reducing agents on the rheological properties of the slurry was studied,especially the relationship between the rheological properties and the thickness of the water film.This study aims to provide a reference for the working performance of slurries that cannot be accurately measured in practical engineering.Methods In view of the above problems,this paper comprehensively studied the rheological properties of different types of water-reducing agents and RSCM.The water film thickness of RSCM with different dosages of three water-reducing agents was determined based on volumetric density.The relationship between the water film thickness and rheological parameters was studied,validating the applicability of the water film thickness model.Subsequently,a prediction model was established to accurately reflect the changes of rheological parameters caused by the original variables such as flocs.The specific test methods are described as follows:After the slurry was stirred,it was poured into the rheometer test vessel.After the test was completed,the rheological curve was obtained by analyzing the data.The classical Bingham model was applied to fit the descending section of the curve to obtain the desired rheological parameters.In order to determine the water film thickness of the slurry,the packing density of the solid particles must be measured first.In this paper,the wet packing density method was

关 键 词：再生微粉 减水剂 流变性能 预测模型 

分 类 号：TB44[一般工业技术] TU528[建筑科学—建筑技术科学]