超吸水聚合物对碱激发泡沫混凝土性能的影响  

Influence of super‑absorbent polymer on properties of alkali‑activated foamed concrete

作　　者：郝伟伟 张树祥 买英东 包超[1] 毛明杰[1] HAO Weiwei;ZHANG Shuxiang;MAI Yingdong;BAO Chao;MAO Mingjie(School of Civil and Hydraulic Engineering,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021

出　　处：《中国粉体技术》2024年第5期70-80,共11页China Powder Science and Technology

基　　金：国家自然科学基金项目,编号:52368044;宁夏回族自治区重点研发项目,编号:2021BEG02014。

摘　　要：【目的】研究超吸水聚合物(super‐absorbent polymer,SAP)对提升以矿渣和再生微粉为主要材料的碱激发泡沫混凝土性能的影响。【方法】调节SAP预吸NaOH溶液的质量分数和SAP掺量(质量分数,下同),考察其对碱激发泡沫混凝土的流动性、吸水率、凝结时间、导热系数、孔隙结构及强度的影响;借助扫描电子显微镜和傅里叶红外光谱分析,从微观角度揭示SAP对泡沫混凝土性能影响机制。【结果】随着SAP掺量的增加,碱激发泡沫混凝土的流动度、凝结时间和导热系数呈下降趋势,但吸水率增大。SAP的掺入会导致碱激发泡沫混凝土孔隙率增大和孔隙分布的改变,掺入预吸水和预吸质量分数为0.4%的NaOH溶液的SAP后,增大了碱激发泡沫混凝土中孔隙直径大于550μm的孔隙比例;掺入预吸质量分数为0.9%的NaOH溶液的SAP后,则增大了碱激发泡沫混凝土中孔隙直径小于250μm的孔隙比例。适量的掺入SAP可以显著改善碱激发泡沫混凝土的抗压、抗折强度,当SAP预吸质量分数为0.4%的NaOH溶液且掺量为0.10%时,碱激发泡沫混凝土的抗压、抗折强度最高。【结论】SAP预吸NaOH溶液处理后,可以明显改善碱激发泡沫混凝土的工作性能、孔隙结构和力学性能。Objective Using recycled concrete powder as an auxiliary cementing material to partially replace slag in the preparation of alkaliactivated foamed concrete helps reduce costs and address the problem of air pollution caused by construction waste crushing dust.However,a higher amount of recycled fine powder usually reduces the performance of concrete.To improve the properties of alkali-activated foamed concrete with recycled micropowder and slag as the main raw materials,internal curing method was considered.The influence of superabsorbent polymer(SAP)on the properties of alkali-activated foamed concrete was studied in the paper.Methods The experiment evaluated the influence of SAP on the fluidity,water absorption rate,setting time,thermal conductivity,pore structure,and strength of alkali-activated foamed concrete by adjusting the mass concentration and dosage of SAP preabsorbed with NaOH solution.Using alkali-activated foamed concrete without SAP as the control group,the study explored the influence of different SAP dosages(0.05%,0.10%,0.15%,0.2%)on the performance of alkali-activated foamed concrete with recycled micropowder and slag as the main raw materials,when SAP was pre-absorbed with 0%,0.4%,and 0.9%NaOH solution.The mechanism by which SAP affects the performance of alkali-activated foamed concrete was investigated by electron microscopy and infrared spectroscopy analysis.Results and Discussion The study on the viability of alkali-activated foamed concrete showed that SAP significantly affected the fluidity of the concrete.With the increase of SAP content,its fluidity showed a general trend of decreasing.The influence of SAP-Water on fluidity was the largest.The water absorption rate of alkali-activated foamed concrete increased gradually with the increase in SAP content.When the content of SAP-Water increased from 0.05%to 0.2%,the water absorption rate increased from 46.7%to 53.5%.Regardless of the mass concentration of NaOH solution added to SAP beforehand,the setting time of alkali-activated foamed conc

关 键 词：泡沫混凝土 超吸水聚合物 再生微粉 碱激发 孔隙结构 

分 类 号：TU528.2[建筑科学—建筑技术科学] TB44[一般工业技术]