Numerical Analysis on Deformation of Soft Organic Soil Improved and Stabilized by Sand Columns

In this chapter, the results of the numerical study investigating the behavior of ground improvement with sand column are presented. Using the Finite Element Method, the study evaluates the settlement behavior and creep process of a soft soil layer with varying sand column dimensions. The numerical model and mechanical properties of the materials used in the study are shown. The behavior of the soft soil is simulated using the Anisotropic Visco-Hypoplastic (AVH) material model. This constitutive model is a high-quality material model for cohesive soils with organic content. It describes the rate dependency of the stiffness as well as the creep and relaxation behavior of the material. In this study, an extensive parameter study is conducted. The results of the study show, that the diameter and length of the sand column do not have a significant influence on the normalized settlement of the system. However, the settlement depends on the area percentage of the sand column and on the surcharge load.