低硅铁尾矿制备轻质泡沫混凝土试验研究  

Experimental Study on Preparation of Lightweight Foamed Concrete by Low Silicon Iron Tailings

作　　者：韩厚胜 李育彪[1,2] 潘梦真 陈坤 张媛 顾雲翔[1,2] 薛璐韬 蹇守卫 HAN Housheng;LI Yubiao;PAN Mengzhen;CHEN Kun;ZHANG Yuan;GU Yunxiang;XUE Lutao;JIAN Shouwei(School of Resources and Environmental Engineering,Wuhan University of Technology,Wuhan 430070,China;Hubei Key Laboratory of Mineral Resources Processing and Environment,Wuhan 430070,China;State Key Laboratory of Silicate Materials for Architectures,Wuhan 430070,China)

机构地区：[1]武汉理工大学资源与环境工程学院,湖北武汉430070 [2]矿物资源加工与环境湖北省重点实验室,湖北武汉430070 [3]硅酸盐建筑材料国家重点实验室,湖北武汉430070

出　　处：《金属矿山》2024年第4期269-274,共6页Metal Mine

基　　金：湖北省重点研发计划项目(编号:2020BCA007)。

摘　　要：为解决低硅铁尾矿堆存量大、利用困难等问题,以杨家湾尾矿库内低硅铁尾矿为矿物掺和料,水泥为胶凝材料,Al粉为发泡剂,制备轻质泡沫混凝土,并考察了水泥掺量、水料比、发泡剂Al粉掺量、激发剂CaO掺量等因素对泡沫混凝土性能的影响。结果表明:在铁尾矿掺量55%、Al粉掺量0.14%、CaO掺量5%、聚丙烯纤维掺量0.3%、稳泡剂掺量0.25%、水料比0.55的条件下,经20±1℃恒温恒湿养护28d,可制备出抗压强度1.84MPa、干密度768.61kg/m^(3)、比强度2.394×10^(-3)Nm/kg的轻质泡沫混凝土,综合性能良好,符合JG/T266—2011《泡沫混凝土》之A08干密度等级、C1强度等级要求。机理分析表明:孔隙率的过度提高会破坏制品内部的孔隙结构,对制品强度造成负面影响;铁尾矿的添加有助于混匀料浆,促进Ca(OH)2的生成,为料浆进一步创造碱性环境,促进钙矾石、C—S—H凝胶等水化产物的生成,其与铁尾矿的交织分布会支撑起孔隙结构,改善力学结构,使泡沫混凝土即使在较低密度下仍表现出较好的力学性能。In order to solve the problem of large stock and difficult utilization of low-silicon iron tailings,lightweight foamed concrete was prepared by using low-silicon iron tailings from Yangjiawan tailings reservoir as mineral admixtures,ce-ment as cementitious material and Al powder as foaming agent.The effects of cement dosage,water-to-material ratio,foaming a-gent Al powder dosage and activator CaO dosage on the performance of foamed concrete were investigated.The results showed that under the condition of iron tailings dosage of 55%,Al powder dosage of 0.14%,CaO dosage of 5%,polypropylene fiber dosage of 0.3%,foam stabilizer dosage of 0.25%and water-to-material ratio of 0.55,the lightweight foamed concrete with compressive strength of 1.84 MPa,dry density of 768.61 kg/m^(3)and specific strength of 2.394×10^(-3)Nm/kg could be prepared after curing 28 days of constant temperature and humidity at 20±1℃.The comprehensive performance was good,which met the requirements of A08 dry density grade and C1 strength grade of JG/T 266—2011 Foamed concrete.The mechanism analysis showed that the excessive increase of porosity would destroy the pore structure inside the products and had a negative impact on the strength of the products.The addition of iron tailings helped to mix the slurry,promoted the formation of Ca(OH)2,further created an alkaline environment for the slurry,and promoted the formation of hydration products such as ettringite and C—S—H gel.The interlaced distribution of these products and iron tailings would support the pore structure and improve the mechani-cal structure,so that the foamed concrete still showed good mechanical properties even at a low density.

关 键 词：低硅铁尾矿 泡沫混凝土 机理 Al粉 比强度 

分 类 号：TD981[矿业工程—选矿] TU528[建筑科学—建筑技术科学]