INFLUENCE OF USING CONTROLLED MODULUS COLUMNS (CMCs) ON LOAD-DEFORMATIONS BEHAVIOR OF SOFT SOILS

Abstract

Civil work faces many challenges, including the difficulty of dealing with soft soil stratum. As the soft soil deposits are mainly characterized by their high voids ratio and their needle-like shaped microscopic particles, they tend to exhibit larger deformation values and lower shear strength compared to other soil types. Thus, to overcome such problems when dealing with soft soil deposits, different soil improvement methods can be used such as Soil improvement using Controlled modulus columns (CMCs), which is one of the types of improvement using rigid inclusions. (CMCs) are a lean sand mix mortar column placed in a network adapted to loads and settling criteria, combined with a granular bed. This distribution bed spreads the applied load between the ground and the CMC. The basal reinforced embankment is a one of the most important applications of ground improvement using CMCs where the loads of a highway or railway track are distributed to the ground and inclusions; moreover, basal reinforced embankments, i.e., piled embankments, can be used as a foundation system for rigid structures. A piled embankment consists of a matrix of CMCs below an embankment constructed using granular materials, in addition to a geosynthetic reinforcement layer (GR) on top of the CMCs. This technique can be built at a fast rate and has a small settlement after construction value, which in turn translates to lower maintenance costs for the structure itself. Furthermore, piled embankment minimizes the horizontal movement of the subsoil, which results in the ability to apply such a method next to sensitive buildings, existing cables, pipelines, susceptible foundations. Generally, CMCs are installed without steel reinforcement when constructing as a ground improvement for facilities that allow this, but there are some locations beneath the same facilities that require a reinforcement CMCs.