The Effect of Nano-Iron Oxide on the Strength and Consolidation Parameters of a Clay Soil: An Experimental Study

The structures do not have enough strength if the foundation of most structures is reliant on weak clayey soil. Accordingly, improving problematic soil with large dispersion is one of the important problems ahead of researchers in geotechnical engineers. One of these types of soils is the clay which creates a lot of problems in the engineering project due to its special properties. A treatment method for the problems caused by these soils is chemical soil stabilization. In this study, by adding nano-iron oxide to clay soil, strength and consolidation parameters of this soil were investigated. For this purpose, index tests were conducted on the natural soil then nano-iron oxide was added to the studied soil with 0.5, 1, 2, 3, 4 and 5% and direct shear, unconfined compressive strength and consolidation tests were carried out. Also, scanning electron microscopy (SEM) was used to evaluate and compare the textural features of the soil, before and after stabilization. The results indicated that adding nano-iron oxide up to 2% can lead to increased strength parameters (including cohesion and internal friction angle) and reduced compressibility and swelling coefficients of the studied soil.