氯氧镁水泥耐久性研究

Study on Durability of Magnesium Oxychloride Cement

通过对活性无机填料的适当选择和配合，并优选磷酸盐类添加剂和氟系扩散剂，制成复合防水剂，进而得到综合性能较好的改性镁水泥。ＸＲＤ分析和ＳＥＭ观察表明，在改性镁水泥的硬化体中，Ｍｇ２Ｐ２Ｏ７和ＡｌＰＯ４等不定形凝胶状耐水相包容着５·１·８相［５Ｍｇ（ＯＨ）２·ＭｇＣｌ２·８Ｈ２Ｏ］，并填充孔隙，使改性镁水泥的耐水性明显提高。大气暴露试验表明，试样表面光洁、无粉化和明显的返卤返霜现象，体积安定性、耐候性、耐干湿交替性均优良。

A type of composite water-resisting admixture has been made by properly selecting and proportioning active inorganic filler, phosphate additive and fluorine diffustant. By means of it, an improved magnesium oxychloride cement with more excellent properties is obtained. XRD and SEM analysis shows that, in harden paste of this improved cement the 5Mg(OH)2·MgCl 2·8H 2O phase is enveloped by amorphous water-resisting gel, Mg2P2O7 and AlPO4, in addition, which will fill in the pores so that the water-resistance of paste is enhacned obviously. The atmospheric-exposed tests show that, the surface of specimes is smooth and clear, and not existing the powdery or effloresency phenomenon. The volumm soundness and resistance to weathering or dry-wet alternating are good.