Modification Effect of Nano-Clay on Mechanical Behavior of Composite Geomaterials: Cement, Nano-Silica and Coastal Soft Soil

To study the modification effect of nano-clay and nano-SiO2 on cement-reinforced coastal soft soil, the effects of the nano-SiO2 and nano-clay on the mechanical properties of cement soil were studied through unconfined compressive and unconsolidated undrained shear tests, and the Duncan-Chang model was used to fit the test results. Results show that adding nano-clay and nano-SiO2 to cement soil improved its compressive and shear strength. The compressive strength and shear strength increased by 18-57% and 3-32%, respectively, with the increase in nano-clay content in a content range of 0-10%. Additionally, nano-clay can enhance the ductility of cement soil. Moreover, nano-clay and nano-SiO2 improve the shear strength by increasing the internal friction angle by 1 degrees-2 degrees and cohesion of 9-25%, and the cement-stabilized coastal soft soil enhanced by nano-SiO2 and nano-clay conforms to the Duncan-Chang model well.