偏高岭土对水泥基胶凝材料耐久性能的影响

The effect of metakaolin on durability of cement based cementitious materials

以粉煤灰、矿粉和硅灰为混合材,与硅酸盐水泥熟料和石膏复合制备一种水泥基胶凝材料,通过内掺法研究偏高岭土对水泥基胶凝材料力学性能和耐久性能的影响,并利用激光粒度分布曲线、XRD和SEM验结果表明,随偏高岭土掺量的增加,水泥砂浆3d强度逐渐下降,28d强度逐渐增加,然后趋于稳定。当掺量超过9%时,强度的改善效果不显著;同时,偏高岭土的掺入,提高了砂浆的抗渗性能、降低了混凝土的氯离子扩散系数,并在偏高岭土掺量为0%-9%范围内作用效果明显。

With fly ash,slag powder and silica fume as the mixed material,composite with Portland cement clinker and gypsum,and the marine cement of 42.5 is made.Through doped metakaolin in the preparation of cement gelled material,study the effect of the amount of metakaolin on the physical properties and durability of cement gelled material.The results showed,with the increase of the amount of metakaolin,the early strength of cement mortar(3d)gradually decline,the strength of 28d is development rapidly,and raised with the increase of the amount of metakaolin.When the amount of metakaolin is more than 9%,the improvement of the strength is not significant.Meanwhile,the incorporation of metakaolin significantly improved the performance of permeability and reduced the diffusion coefficient of chloride ion,and the effect was obvious in the range of 0%~9%.And using Particle size analysis,XRD and SEM to analyzed the mechanism of metakaolin.