Experimental Studies on Properties of Modified Foam Magnesium-oxychloride Cement

摘要

The experiment mainly studied various admixtures modified effect of foam magnesium oxychloride cement, with the introduction of various kinds of phosphate, sulfate and iron vitriol to reduce the density of foam magnesium oxychloride cement,improve the strength and softening coefficient of foamed cement.The experiment using admixtures including iron alum, NaH2PO4, MgSO4, and the addition amount of 0.3％, 0.6％ and 0.9％ respectively.According to the basic formula of the foaming magnesium oxychloride cement, the molar ratio of MgO/MgCl2 wax 7∶1, the concentration ratio of MgCl2 was 0.26 mol/L, the fly ash was 20％, the content of water reducing agent (polycarboxylic acid)was 0.2％, PP fiber wax 0.3％, made in accordance with various performance tests of standard modules,and to join the hydration products of module after the modification agent XRD mineralogical analysis and microstructure analysis by SEM.The results show that the foam magnesium oxychloride cement adding iron vitriol can make the module of the bulk density decreased, the optimum can reach 272.5 kg.m-3;And the addition of NaH2PO4 can increase the softening coefficient of foam magnesium oxychloride cement,thus to improve its water resistance;And the addition of MgSO4 can promote the generation of 5Mg(OH)2·MgCl2·8H2O phase inside the module, so that the strength of the article is enhanced, 28 day compressive strength reach 0.87 MPa.