摘要
现有研究表明不同改性剂对碱式硫酸镁水泥(BMSC)中517相的生长有影响。本工作使用六种不同羟基含量的改性剂,借助X射线衍射仪、扫描电子显微镜、拉曼光谱仪和压汞仪研究了改性剂相同质量掺量下BMSC的力学强度、物相组成和微观结构。实验结果表明,添加富羟基的磷酸二氢钠和磷酸二氢钾试样中517相含量最高,长径比最大,抗压强度较对照组提升近一倍,软化系数接近1.00;BMSC中孔隙主要为晶间孔,长径比大的517相使孔径分布更集中、总孔隙率更低。BMSC耐水性能与517相含量、形貌有关,使用富羟基的改性剂能促进517相的结晶生成,从而提高517相含量及其长径比,改善其耐水性能。
Recent studies have shown the effect of different modifiers on the growth of endogenous 517 phase ofbasic magnesium sulfate cement(BMSC).In this work,the mechanical strength,phase composition and microstructure of BMSC with the same modifier admixture were investigated using six modifiers with different hydroxyl content with the help of X-ray diffractometer,scanning electron microscope,Raman spectrometer and mercury piezometer.The results show that the 517 phase content is the highest and the aspect ratio is the largest in the specimen with high hydroxyl content of sodium dihydrogen phosphate and potassium dihydrogen phosphate.The compressive strength is nearly doubled compared with that without addition,and the softening coefficient are close to 1.00.The pores in BMSC are mainly intergranular pores,and the 517 phase with large aspect ratio let to more concentrated pore size distribution and lower total porosity.The water resistance of BMSC is related to the content and morphology of 517 phase,and the use of hydroxyl-rich modifier can promote the crystallization of 517 phase,thus increasing the content of 517 phase and its aspect ratio to improve water resistance.
作者
朱倍
徐迅
胡海龙
余波
朱妍
甘露
ZHU Bei;XU Xun;HU Hailong;YU Bo;ZHU Yan;GAN Lu(School of Civil Engineering and Architecture,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;School of Materials and Chemistry,Southwest University of Science and Technology,Mianyang 621010,Sichuan,China;Guangxi Key Laboratory of Disaster Prevention and Engineering Safety,Guangxi University,Nanning 530001,China;Southwest University of Science and Technology Analytical Testing Center,Mianyang 621010,Sichuan,China;School of Civil Engineering and Construction,Guangxi University,Nanning 530001,China;Key Laboratory of Ministry of Education for Engineering Disaster Prevention and Structural Safety,Guangxi University,Nanning 530001,China)
出处
《材料导报》
CSCD
北大核心
2023年第19期97-102,共6页
Materials Reports
基金
四川省重点研发计划(2023YFSY0019)
广西防灾减灾与工程安全重点实验室开放课题项目(2020ZDK006)
西南科技大学实验技术研究项目(21syjs-32)
广西壮族自治区杰出青年科学基金(2019GXNSFFA245004)
广西壮族自治区自然科学基金(2018GXNSFAA281344)。
关键词
碱式硫酸镁水泥
改性剂
水化产物
微观结构
耐水性能
basic magnesium sulfate cement
modifier
hydration products
microstructure
water resistance
