偏高岭土在建筑外墙腻子中的应用

Application of Metakaolin in the External Wall Putty

腻子黏结强度不足和抑制泛碱能力差是引起墙体起皮、泛白以及龟裂等现象的主要原因。基于腻子成分对比试验,研究了偏高岭土掺量对建筑外墙腻子黏结强度、抗折强度的影响,确定了成本控制下腻子的最佳配合比,分析了偏高岭土对腻子泛碱的抑制作用。试验结果表明,偏高岭土对腻子的黏结强度具有提升作用;随着偏高岭土掺量的增加,腻子的抗折强度逐渐增强,当偏高岭土掺量为3%时,其强度达到最大值;适当增大偏高岭土量,减少胶粉量,可以在保证腻子强度情况下,显著降低生产成本;偏高岭土对墙体泛碱具有抑制作用,其掺量为3%时,抑制效果最为明显。

The insuffcience of bond strength and the lack of restraining whiskering on the putty are the main reasons for the peeling,whiting and fracturing in the wall. Based on the method of comparing the composition of putty,studied the influence of the mixing amount of metakaolin on the bond strenth and the flexural strength of the exterior wall putty,determined optimum proportion of putty under the condition of controlling cost,analyzed the function of metakaolin in inhibiting the whiskering of wall. The test results show that metakaolin can enhance the bond strength of putty. With the augment of metakaolin,the flexural strength gradually increased,when the mixing amount of metakaolin is 3%,its strength reaches maximum; Added the amount of metakaolin,reduced the amount of powder,it can reduced the cost significantly with guaranteeing the strength of putty. Metakaolin can inhibit the whiskering of wall. When the addition was 3%,the effect of inhibiting whiskering is the most obvious.