摘要
用硅灰(SF)和不同温度煅烧后MgO制备水化硅酸镁(MgO-SiO2-H2O,M-S-H)胶凝材料,研究其流动度、凝结时间、pH值与M-S-H胶凝材料强度及膨胀特性的相互关系。采用X射线衍射和热重分析等测试手段分析了不同温度煅烧的MgO对MgO-SF净浆水化产物和M-S-H结构的影响。结果表明:随着煅烧温度增加,MgO衍射峰强度增加,峰宽变窄,晶粒尺寸增加,活性降低。1150℃煅烧MgO制备的净浆中Mg(OH)2和M-S-H物相含量高,且M-S-H硅氧四面体聚合程度最大。1150℃煅烧MgO制备的MgO-SF流动度适中易成型(净浆和砂浆流动度分别为129 mm和206 mm),净浆pH值和凝结时间适中,砂浆强度高、自由膨胀率(εt)最小。εt与Mg(OH)2的含量变化幅度正相关。
The relationships among the fluidity,setting time,and pH value of hydrated magnesium silicate(MgO-SiO2-H2O,M-S-H)prepared by silica fume(SF)and MgO after calcination at different temperatures were investigated,and the strength and shrinkage characteristics of M-S-H cementious materials were analyzed.The effect of MgO on the hydrated products of MgO-SF and the structure of M-S-H at different calcination temperatures was investigated by X-ray diffraction and thermogravimetric analysis.The results show that the intensity of MgO diffraction peak increases,the peak width becomes narrower,the grain size increases,and the activity decreases as the calcination temperature increases.The contents of Mg(OH)2 and M-S-H in the pure pulp prepared by calcining MgO at 1150℃are the highest,and the degree of polymerization of M-S-H silicon tetrahedron becomes the maximum value.The MgO-SF pulp and mortar slump prepared by calcining MgO at 1150℃are 129 mm and 206 mm,respectively,in accordance with the large-flow concrete.The pH value and setting time of the pulp are moderate,the mortar strength is high,and the dry shrinkage rate(εt)is the minimum value.εt is positively correlated to the change in Mg(OH)2 content.
作者
王倩
武志红
张国丽
张路平
郑海康
WANG Qian;WU Zhihong;ZHANG Guoli;ZHANG Luping;ZHENG Haikang(College of Materials Science and Engineering.Xian University of Architecture and Technology.Xian 710055,China;State Key Laboratory of Advance Refractories,Sinosteel Luoyang Institute of Refractories Research Co.,Ltd,Luoyang 471039,Henan,China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2020年第5期682-688,共7页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金项目(51974218)
西安建筑科技大学基础研究基金(JC1496)
先进耐火材料国家重点实验室开放基金(SKLAR201905)。
关键词
水化硅酸镁
自由膨胀率
水化产物
氧化镁
hydrated magnesium silicate
drying shrinkage characteristics
hydration product
magnesium oxide
作者简介
第一作者:王倩(1994一),女,硕士研究生;通信作者:武志红(1974-),男,博士,副教授。
