轻烧白云石对碱矿渣水泥凝结硬化性能的影响  

Effect of Light-Calcined Dolomite on Setting and Hardening Properties of Alkali-Activated Slag Paste

作　　者：陈登 杨涛[2] 陈森森 Chen Deng;Yang Tao;Chen Sensen(College of Civil Engineering,Suzhou University of Science and Technology,Suzhou,Jiangsu 215011;College of Materials Science and Engineering,Yancheng Institute of Technology,Yancheng,Jiangsu 224051;Nanjing Kangtai Construction Grouting Technology Co.,Ltd.,Nanjing,Jiangsu 210019)

机构地区：[1]苏州科技大学土木工程学院,江苏苏州215011 [2]盐城工学院材料科学与工程学院,江苏盐城224051 [3]南京康泰建筑灌浆科技有限公司,江苏南京210019

出　　处：《非金属矿》2022年第3期11-14,共4页Non-Metallic Mines

基　　金：江苏省自然科学基金(BK20220639);江苏省高等学校自然科学研究项目(20KJB560007);安徽省先进建筑材料工程实验室开放课题(JZCL006KF)。

摘　　要：以碳酸钠为弱碱性激发剂制备的碱矿渣水泥凝结时间长且早期强度发展缓慢。本试验采用轻烧白云石为辅助性碱激发剂以加速反应进程,分析了煅烧温度(800℃、900℃、1000℃)和保温时间(0.5 h、1.0 h、1.5 h)对轻烧白云石粉矿相组成的影响,研究掺轻烧白云石的碳酸钠激发矿渣水泥在常温养护条件下的凝结时间和早期抗压强度,并采用X射线衍射(XRD)仪和热重分析(TGA)仪表征水泥硬化体的产物组成。结果表明,提高煅烧温度或延长保温时间均可促进白云石粉的脱碳和脱羟基反应,提升轻烧白云石粉中活性矿相产物比重,进而提高碱激发反应速率,缩短浆体凝结时间,终凝时间控制在105~260 min范围内,水泥硬化体28 d抗压强度提升至50.3 MPa。轻烧白云石粉的最优煅烧温度为900℃,调整保温时长可调控浆体的凝结时间。The alkali-activated slag cement prepared with sodium carbonate as weak alkaline activator usually has long setting time and slow early-age strength development.In this study,calcined dolomite was incorporated in the cement paste to accelerate the reaction process.The influences of calcination temperature(800℃,900℃,1000℃)and duration(0.5 h,1.0 h,1.5 h)on the phases evolution of calcined dolomite powder were analyzed,the setting time and early-age compressive strengths of calcined dolomite-modified sodium carbonate-activated slag cement paste cured at the ambient temperature were measured,and the phases evolution of cement paste were characterized by XRD and TGA.The results showed that enhancing the calcination temperature and extending the calcination duration could improve decarbonization and dehydroxylation of dolomite powder,increase the proportions of reactive mineral phases in the calcined dolomite powder,and thus improve the alkali-activation kinetics of sodium carbonate-activated slag cement paste.The final setting time of cement paste were decreased to the range of 105-260 min,and the 28 d compressive strength was improved to 50.3 MPa.The optimum calcination temperature for processing the calcined dolomite powder is 900℃.Adjusting the calcination duration was helpful in controlling the setting time of cement pastes.

关 键 词：碱矿渣 轻烧白云石 碳酸钠 凝结时间 抗压强度 

分 类 号：TU528[建筑科学—建筑技术科学]