The Use of Stone Columns to Reduce the Settlement of Swelling Soil Using Numerical Modeling

Document Type : Original Article

Authors

Department of Civil Engineering, Islamic Azad University, Estahban Branch, Estahban, Iran.

10.15412/J.JCEMA.12010203

Abstract

The existing soils in the nature that is used for construction cannot necessarily bear the loadings on the structure. For example, in granular soils, the natural soil may be very loose and show a lot of elastic settlement. Sometimes, there are soft layers, saturated clay and swelling soils at the lower depths, which may cause significant settlement in the structure in terms of foundation load and clay layer thickness. To avoid such settlements, it is necessary to use certain techniques to improve the soil condition. One of the methods that have recently been widely used to reduce the settlement of soft soils and swelling soils is stone columns or single piles. In this research, first of all, the parameters in need for the analysis will be gained by using the experimental data, and then, the static and dynamic behavior of the confined stone columns is examined with geotextile and without geotextile by a group and single manner as in two-dimensional form using Plaxis numerical method of the finite element and the impact of the following parameters will be investigated in both static and dynamic modes: Column length, column diameter, single and group behavior of columns, and soil cohesion effect on the behavior of the confined stone column in geotextile and reduction of soil settlement during use of stone columns. The results of this research indicate correct understanding of the use of geotextile (Woven Geotextile with a specific elastic normal strength) to prevent the camber and the settlement of the column and increase of the strength and bearing capacity of the column.

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