The presence of colloidal nano silica in sandy soils: a review

Nanotechnology has been with us as a science since the first nanoscale features were observed under a microscope. Nanotechnology is an emerging technology and one of the key components of the technological advances of the present century. The use of materials with nanometer-based structures has led human knowledge to develop and provide solutions to produce superior products in the future. With the advent of modern nanotechnology and the study of the unique properties of nanoparticles, the field of their use was provided in many branches of engineering, of which geotechnical engineering is no exception. In this paper, while introducing colloidal silica nanoparticles and their gelation, study on the important characteristics and effect of this type of nanoparticles on sandy soils properties will be discussed. In fact, we discussed previous studies on the use of colloidal nano silica in sandy soil, their properties, their effects on soil, and the equipment used in nanotechnology . The current review is an attempt to summarize the applications of nanotechnology in geotechnical engineering. Furthermore, this paper plans a comprehensive review on characteristics of colloidal nano silica, its effect on curing approaches and aging, its behavior upon the addition with sandy soil in terms of strength improvement, liquefaction potential, cyclic properties, hydraulic conductivity, and compressibility. Lastly, the optimal percentage of nano silica for various purposes was presented.