Installation of TENAX LBO geogrids prior
to spreading and compaction of fill material
Compaction of fill material over TENAX LBO
for stabilisation of the foundation soil
Base reinforcement of the road embankment
of the Rome-Fiumicino Airport High Way
Subsoil stabilisation with nonwovens and
integral geogrid TENAX
Whenever a paved or unpaved road needs to be built
on soft or saturated soil, settlement may take place during or after
construction, with serious consequences for the life span of the
The base layer, made-up from granular material, can sink into the
foundation soil, and horizontal and vertical movement capable of
forming ruts can occur at the base.
To avoid these phenomena, it’s
necessary to place one or more layers of reinforcing geogrids having
the ability to confine the aggregate and distribute the load.
Geosynthetics allow for the reduction in the thickness of the base layer and they
increase the service life of the structure whilst utilizing lower
grade fill material.
The use of a TENAX LBO geogrid and/or TENAX 3D Grids three-dimensional geogrids minimizes
the horizontal deformation of the aggregate base layer, limiting
its deterioration and conserving its thickness.
TENAX LBO geogrids
and TENAX 3D Grids are a mesh structure having apertures in which granular material
is confined by interlocking.
Laboratory and on-site testing
have demonstrated the effectiveness of TENAX geogrids for the
minimization of settlement rutting and for the reduction of
the thickness required for the road base.
Road base thickness: 30 mm
Subgrade CBR: 1.0
The reduced likelihood of deformation in the base layer limits the formation of “fractures” in elements beneath the base itself.
In fine-grained sand or clay like soils, it’s advisable to use a finer mesh multi-layer geogrid such as the TENAX 3D Grids MS series.
When the grain size characteristics of the aggregate base soil are not suitable to act as a filter of the subgrade, it’s necessary to prevent the possibility that the former, as a consequence of the compression and relaxation cycles to which it is subjected, can migrate into the upper layer.
Under these circumstances, the use of a TENAX GT geocomposite, made from a reinforcing TENAX LBO geogrid laminated to a light nonwoven geotextile and functioning as a separating membrane, has proved effective.
The interlocking between the geogrid and the soil particles is not prevented thanks to the geotextile’s high local deformability in the openings between the geogrid meshes.
If the road is to be constructed in an area with a high water table, placing a filtering/draining TENAX TENDRAIN geocomposite at the base of the structure provides an excellent means for draining the structure itself, preventing backfill from sinking and contributing to the distribution of load.
TENAX 3D Grids MS
TENAX LBO HM geogrids and TENAX GT HM geocomposites
TENAX LBO geogrid
TENAX GT geocomposite
TENAX TENDRAIN geocomposite
The base of a road on soft subgrade will quickly deform, with rutting at the surface and difficulty of movements for the vehicles.
Closely spaced layers of TENAX geogrids considerably stiffen the road base, while TENAX geocomposites maintain the separation between the fill and the subgrade while providing positive drainage.
TENAX geosynthetics provide the drainage, separation and reinforcement required to stabilize the base of roads on soft subgrade.
1. Soft soil
2. Granular fill
3. Soil cracking
4. Deformed profile
5. Asphalt or concrete pavement
6. TENAX bi-oriented geogrids
7. TENAX TENDRAIN, TENAX TN, TENAX GT geocomposites
The use of TENAX bi-oriented geogrids allows to:
1) Reduce the progressive failure of the flexible paved roads: The road service life can be increased up to a factor of 10 without changing the properties of the road components.
2) Reduce the thickness of the aggregate base layer without loosing in performances and structural capacity.