Geocells confine infill material within interconnected cells, preventing lateral
movement and distributing loads more evenly across weak soils.
Geocells confinement occurs when a volume of material is confined by a three-
dimensional geosynthetic system. The Geocell stabilization mechanism limits
horizontal infill soil deformation via the geocell walls, thereby confining the infill soil.
The limitation of horizontal deformation is based on four factors.
a) Hoop tension forces in the cell walls.
b) Resistance from the surrounding cells.
c) Friction between cell walls and infill material.
d) Connection strength of joined walls.

Under vertical load, horizontal earth pressure is restrained by the cell walls. The
resulting strains in the cell walls mobilize hoop stresses within the loaded cell (see
figure below). The magnitude of the activated hoop stress depends on the geocell

material, stress-strain behavior, magnitude of load, number of load cycles, location of
the applied load, type and properties of infill material, and the foundation
characteristics. The hoop stresses and resistance provided by surrounding cells
restrict lateral deformation of the fill by producing confining stresses σ3D (Figure 3).
The intensity of the confining stresses depends on the height to diameter ratio of the
geocell, the height of surcharge and the tensile properties of the geocell. The
confined zone shown in Figure 3) includes two parts.

1) Cell height.
2) Limited thickness above and, possibly, beneath the geocell.

What makes Neoloy® Tough-Cells different from HDPE geocells?
Neoloy® Tough-Cells are made from a Novel Polymeric Alloy (NPA) that provides
higher tensile strength, higher stiffness and superior resistance to plastic deformation
compared to traditional HDPE geocells.
According to ISO 18228-5: “ The geometry and material properties of the geocell are
key properties to maximize the effect of stabilization
and to validate it for the design life of the project. The key material properties of the
geocell, related to hoop tension forces in the cell walls, are its elastic stiffness and
resistance to permanent deformation. These properties contribute to the magnitude
of the stabilization for the design life. The stiffer the geocell, the higher the hoop
tension stress can be and, thus, the improvement of the geocell-stabilized layer for
the entire design life is dependent on the geocell material properties (tensile,
dynamic stiffness and creep) to assure very low deformation of the confining cell
walls, i.e., less than 2% accumulated for the entire design life (a higher value can
invalidate stabilization)”.

Neoloy® Tough-Cells are the only geocells that can guarantee less than 2%
accumulated deformations under heavy loads, guaranteed for a design life of up to
75 years.
HDPE Geocells will exceed 2% deformation after only 4 months under the same
conditions. Therefore HDPE Geocells can only be used for temporary light load
applications.

Geocells made from stiff Novel Polymeric Alloys (NPA), also known as Tough-Cells
are widely used in infrastructure applications including roads, railways, runways and
loading platforms.
Geocells made from softer materials, such as HDPE, can be used for temporary light
load applications, such as slopes protection and channels.