The effects of nanoparticles on early age compressive strength of ash-based geopolymers
The effects of nanoparticles on early age compressive strength of ash-based geopolymers
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DOI：
10.1016/j.ceramint.2012.02.021
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发表时间：
2012-08
影响因子：
5.2
通讯作者：
Shadi Riahi;A. Nazari
中科院分区：
文献类型：
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作者：
Shadi Riahi;A. Nazari
在目前的工作中，采用田口法设计了含有97wt％稻壳灰+粉煤灰和3wt％纳米氧化铝+纳米二氧化硅的灰基地质聚合物在水养护2天和7天时的抗压强度。考虑了4个因素，包括纳米二氧化硅的百分比（1、2和3wt% 3个水平）、烘箱固化温度（25、70和90°C 3个水平）、烘箱固化时间（2、4和8h 3个水平）和NaOH浓度（5、8和12M 3个水平）。利用L9田口阵列，对制备的样品进行了9组实验。碱活化通过氢氧化钠（NaOH）和硅酸钠（Na2SiO3）溶液的混合物进行。通过方差分析（ANOVA）方法对所得结果进行评价，以确定各因素的最佳水平。在所有生产的样品中，纳米二氧化硅的最佳含量、烘箱固化温度和烘箱固化时间分别为3wt%、90℃和8h。烘箱固化时间并不是决定抗压强度的重要因素。为了验证方差分析建议的最佳条件的准确性，根据 2 天和 7 天水固化方案的最佳条件制作并测试了压缩样本。从这种情况获得的抗压强度高于在 2 天和 7 天水养护方案的 9 个系列实验中提出的抗压强度。
In the present work, compressive strength of ash based geopolymers containing 97wt% rice husk ash+fly ash and 3wt% nano alumina+nano silica has been designed by Taguchi method at 2 and 7 days of water curing. 4 factors including the percentage of nano silica (at 3 levels of 1, 2 and 3wt%), oven curing temperature (at 3 levels of 25, 70 and 90°C), oven curing time (at 3 levels of 2, 4 and 8h) and NaOH concentration (at 3 levels of 5, 8 and 12M) were considered. By utilizing L9 Taguchi array, 9 series of experiments were conducted on the prepared specimens. The alkali activating was done by a mixture of sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) solutions. The obtained results were evaluated by analysis of variance (ANOVA) method to determine the optimum level of each factor. In all produced specimens, the optimum level of nano silica, oven curing temperature and oven curing time were 3wt%, 90°C and 8h, respectively. The oven curing time was not an important factor for determining the compressive strength. To validate the accuracy of the optimum conditions suggested by ANOVA, compressive specimens were made and tested in accordance to the optimum conditions for each of 2 and 7 days water curing regimes. The obtained compressive strength acquired from this situation was higher than those of proposed in 9 series experiments for each of 2 and 7 days water curing regimes.