Weak soils limit embankment performance
Building embankments over very weak soils presents critical geotechnical challenges. Very soft soils with low undrained shear strength (<15 kPa) lead to excessive settlements, lateral deformation, and low global stability. In many cases, there is insufficient bearing capacity to support embankments.
Traditional solutions such as stone columns often fail in these conditions. Without confinement, columns deform excessively, lose material into surrounding soils, and cannot effectively transfer loads.
Engineers require a solution that provides radial confinement, improves load transfer, and accelerates consolidation while minimizing the use of imported aggregates.
MIRAFI Mirapile geotextile encased columns
MIRAFI® Mirapile geotextile encased columns (GEC) are designed to solve deep foundation challenges using minimal locally available sand or gravel.
This proven technology uses a seamless, high-strength geotextile encasement to provide circumferential confinement to vertically installed aggregate columns. The result is a semi-flexible foundation system that reduces settlement, increases bearing capacity, and enables construction over very soft soils.
How it works: confinement-driven performance
MIRAFI Mirapile GECs improve ground performance through controlled confinement and load transfer mechanisms.
The seamless geotextile encasement provides high circumferential tensile strength, preventing radial expansion (bulging) of the column under load. This confinement allows the aggregate core to maintain its integrity without the need for binding materials such as cement.
Vertical loads from the embankment are preferentially transferred to the stiffer columns. As the column attempts to expand, the encasement mobilizes ring tensile forces, increasing composite stiffness. This creates soil arching, which reduces vertical stress on the surrounding soft soils and controls settlement.
Applications in infrastructure and ground improvement
MIRAFI Mirapile GECs are used to construct stable foundations in very soft soil conditions across a range of infrastructure applications. These include embankments for roads, highways, railways, and bridge ramps, as well as dikes and flood protection systems. They are also applied in industrial platforms, airport infrastructure, and seismic areas where column integrity under cyclic loading is critical.
The system is suitable for large-area ground improvement, enabling the development of previously inaccessible terrains such as industrial zones and parking areas.
Installation is carried out vertically to the depth of stable soils using specialized equipment by soil improvement contractors.
Engineered performance and system features
MIRAFI Mirapile GECs are designed for long-term performance under demanding geotechnical conditions.
The system offers high ring stiffness and variable tensile strengths to match project requirements. The seamless casing ensures consistent confinement and mechanical resistance over the design life. The geotextile provides strong creep resistance and maintains structural performance under sustained loads.
Multiple column diameters and strength classes allow for flexible design. The system integrates with basal reinforcement and working platforms to optimize global stability and construction logistics. Design support services are available to ensure correct specification and performance validation.
