改性硫氧镁水泥物相组成及性能研究.pdfVIP

学兔兔 中国科技核心期刊 新 建魄 改性硫氧镁水泥物相组成及时生链砷穷 吴成友 ，余红发1,2,3文静 ，董金美1,4 (1．中国科学院青海盐湖研究所，青海 西宁 810008；2．青海大学 土木工程学院，青海 西宁 810008 3．南京航空航天大学土木工程系，江苏 南京 210016；4．中国科学院大学，北京 100049) 摘要：研究了有机酸CA改性的硫氧镁水泥物相组成、抗压强度及耐水性能。改性后的硫氧镁水泥出现了大量新相，且Mg(0H) 的生成量明显减少。利用化学元素分析方法确定了该新相的组成为5Mg(OH) ·MgSO4~5H20(515相)。采用SEM确定515相是一种 针状晶体。利用TG—DSC方法研究了其分解规律。利用XRD跟踪试验确定了515相的生成过程并结合改性剂对氧化镁水化后pH 值的影响，探讨了改性剂对硫氧镁水泥的改性机理。改性后水泥相的抗压强度和耐水性能明显提高。 关键词：硫氧镁水泥；改性剂；物相组成；抗压强度；耐水性 中图分类号：TQ177．5 文献标识码：A 文章编号：1001—702X(2013)05—0068—05 Study of phase compositions and properties of modified magnesium oxysulphate cement Chengyou ，YU Hong~a“。 ，WEN Ji ，DONG Jinmei“ (1．Qinghai Institute of Salt Lake，Chinese Academic of Sciences，Xining 810008，Qinghai，China： 2．Department of Civil Engineering of Qinghai University，Xining 810008，Qinghai，China： 3．Department of Civil Engineering，Nanjing University of Aeronautics and Astronautics，Nanjing 210016，Jiangsu，China； 4．Graduate University of Chinese Academy of Sciences，Beijing 100049，China) Abstract：Phase compositions，compressive strength and water resistance of magnesium oxysulphate cement modified by organ- ic acid CA were studied．Mass of new phase appears and the content of Mg(OH)2 decreases in modified cement．This new phase can be expressed by 5Mg(OH)2。MgS04。5H20(515 phase)determined by chemical element analysis．SEM analysis has proved that the microstructure of the 515 phase is needle-like crysta1．The law of thermal decomposition of this new phase has been studied by TG-DSC method．The process of formation of 515 phase has been studied by d