ABSTRACT
The design and construction of the structures on soft soil deposits have been, historically, a challenge for the geotechnical engineers so that serviceability and limit state conditions as well as cost and time schedule are properly addressed. The column filling material can be sand or gravel; the latter, however, provides higher overall stiffness of the encased column, but has to be compatible with the geosynthetic material used to prevent its damage. The geosynthetic encasement also controls the column diameter, minimizes material losses, increases overall column stiffness, and avoids granular column contamination, thus preserving the drainage features. Encased columns can be installed with or without lateral displacement of the soft soil, thus two different methods are generally available with regards to the geotextile encased column (GEC) construction technology. The design of GECs-supported embankments requires high-quality soft soil parameters to be obtained in a well-specified and controlled site investigation program.
