硅镁胶凝材料的耐水性研究

关键字：镁质胶凝材料,硅质填料,耐水性,水硬性

（1.重庆大学 材料科学与工程学院，重庆  400045；2.山东省建筑科学研究院，山东 济南  250031）

    摘要：活性硅质填料对改善镁质胶凝材料的耐水性有重要作用，在活性氧化镁和氯化镁摩尔比为7的条件下设计配比，研究了不同硅质填料和磷酸系激发剂对镁质胶凝材料耐水性的影响，确定了对镁质胶凝材料耐水性提高最为显著的硅质填料和激发剂，并进行了镁质胶凝材料的水下不分散性和水硬性试验。结果表明：在采用30%的硅灰作为填料、1%的磷酸二氢钠作为激发剂时，制品的软化系数提高显著、耐水性最好，并实现了镁质胶凝材料作为一种气硬性材料在水中的成型硬化，改性后镁质胶凝材料的强度在水中长期保持稳定。
    关键词：镁质胶凝材料；硅质填料；耐水性；水硬性
    中图分类号：TU502             文献标识码：A        文章编号：1001-702X（2017）06-0035-05

Investigation on the water-resistance of silica-magnesia cementitious material
CUI Hongtao1，2，JIN Lutong2，PENG Jiahui1，WANG Zifu2，ZHANG Xingfu2
（1.College of Materials Science and Engineering，Chongqing University，Chongqing 400045，China；
2.Shandong Academy of Building Research，Jinan 250031，China）

    Abstract：Active silica stuffing has an important influence on the water-resistance of magnesia cementitious material. Material proportioning was designed under the active MgO/MgCl2 molar ratio of 7，and the influences on material＇s water-resistance by different silica stuffing and phosphates-based activators were studied. The optimal proportioning of silica stuffing to activator was determined on the basis of the extent to which the water-resistance of magnesia cement is enhanced，and the experiment of non-dispersion and water-hardening was undertaken. The test results show that coefficient of softness of the material could be enhanced dramatically with best water-resistance by using 30% silica fume as stuffing and 1% monosodium phosphate as activator. By this proportioning，the water-resistance of magnesia cement is dramatically enhanced，and a hardening process under water has been achieved in the typical air-hardening magnesia cementitious material，with a long-time strength stability.
    Key words：magnesia cementitious material，silica stuffing，water-resistance，water-hardening