The effect of nanoKaolinite on liquefaction resistance of liquefiable sand

Nanotechnology has played a significant role in the improvement of the problematic soils. This study was to investigate the effect of the nano-kaolinite concentration on the liquefaction resistance of liquefiable sand from Gorgan, Iran. To examine the influence of the nano-kaolinite concentration on the liquefaction resistance of nano-kaolinite-sand mixtures, three different nano-kaolinite concentrations (namely 3%, 6%, and 9%) were prepared. In order to simulate the earthquake impact on the liquefiable sand, cyclic triaxial tests were conducted on pure sand and nano-kaolinite-sand mixtures. Cyclic triaxial test was repeated two times for each nanokaolinite- sandy soil mixture and the mean and standard deviation values of total 24 tests were obtained. Based on the obtained results, nano-kaolinite concentration has a contradictory effect on the liquefaction resistance of the studied soil. It was found that the influence of nano-kaolinite concentration on liquefaction resistance of the sand should be evaluated using a critical value of nano-kaolinite concentration. Below the critical value (under 6% nano-kaolinite content), liquefaction resistance decreases as the nano-kaolinite concentration increases. Beyond such a value, liquefaction resistance enhances with an increase in nano-kaolinite concentration. The results showed that the nano-Kaolinite–sand samples with 9% nano-Kaolinite concentrations show liquefaction resistance much more than untreated soil. It was also observed that at the same cyclic stress ratio, liquefaction resistance and axial strain of samples decreases as the confining pressure increases.