Exposed drained geomembranes

Exposed drained geomembranes are the most widely used solution for waterproofing hydraulic infrastructures, due to their rapid installation, ease of inspection, accessibility and reparability if necessary, even under water, during the whole life of the system. The geomembrane is fastened to the structure by various anchorage systems.

Exposed geomembrane with tensioning profiles

Tensioning profiles, developed and patented by Carpi, are used on rigid structures with a high pull-out resistance facing. They keep the geomembrane taut on the surface of the structure and act as upstream drains, collecting seepage water and preventing it from seeping into the structure.

Applications: RCC dams, shafts, pumped storage reservoirs
  • High durability
  • Excellent resistance to
    high water pressure
    and high water speed
  • Effective drainage system

Exposed geomembrane with anchor trenches

The face anchorage of the geomembrane is made in vertical trenches cut into the granular facing during construction and compaction. Various configurations, including patented tensioning trenches, are available. The anchorage system and the perimeter seals allow for settlements and differential movements.

Applications: Embankment dams, Reservoirs, Pumped storage reservoirs, Canals (Granular material)
  • Resists settlements
    and differential movements
  • Quick construction,
    early commissioning
  • Low environmental footprint

Exposed geomembrane with anchor wings

In this patented solution, the face anchorage of the geomembrane is made by welding it on the geomembrane anchoring wings embedded in the facing during its construction, which reduces the installation time of the waterproofing system, and obtains a deformable anchoring system adapting to settlements. The perimeter seals are designed to accommodate differential movements.

Applications: Embankment dams, Hardfill dams, Tailings dams
  • Resists settlements
    and differential movements
  • Quick construction,
    early commissioning
  • Cost-effective solution

Exposed geomembranes with deep point anchors

Where the structure in contact with the water does not have the necessary pull-out resistance, such as embankments or weak subgrades, special anchors must be used to ensure that water or wind action does not lift the geomembrane. The face anchorage of the geomembrane is carried out at points, by a patented system of deep anchors, grouted or earth anchor type, embedded in the compacted granular facing. The perimeter seals are designed to adapt to differential movements.

Applications: Embankment dams, Hardfill dams, Cofferdams, Reservoirs, Canals (low cohesion granular material)
  • Ensure stability on subgrades
    with low pull-out strength
  • Resists settlements
    and differential movements
  • Low environmental footprint

Exposed geomembrane with tensioning profiles

Tensioning profiles, developed and patented by Carpi, are used on rigid structures with a high pull-out resistance facing. They keep the geomembrane taut on the surface of the structure and act as upstream drains, collecting seepage water and preventing it from seeping into the structure.

Applications: RCC dams, shafts, pumped storage reservoirs
  • High durability
  • Excellent resistance to
    high water pressure
    and high water speed
  • Effective drainage system

Exposed geomembrane with anchor trenches

The face anchorage of the geomembrane is made in vertical trenches cut into the granular facing during construction and compaction. Various configurations, including patented tensioning trenches, are available. The anchorage system and the perimeter seals allow for settlements and differential movements.

Applications: Embankment dams, Reservoirs, Pumped storage reservoirs, Canals (Granular material)
  • Resists settlements
    and differential movements
  • Quick construction,
    early commissioning
  • Low environmental footprint

Exposed geomembrane with anchor wings

In this patented solution, the face anchorage of the geomembrane is made by welding it on the geomembrane anchoring wings embedded in the facing during its construction, which reduces the installation time of the waterproofing system, and obtains a deformable anchoring system adapting to settlements. The perimeter seals are designed to accommodate differential movements.

Applications: Embankment dams, Hardfill dams, Tailings dams
  • Resists settlements
    and differential movements
  • Quick construction,
    early commissioning
  • Cost-effective solution

Exposed geomembranes with deep point anchors

Where the structure in contact with the water does not have the necessary pull-out resistance, such as embankments or weak subgrades, special anchors must be used to ensure that water or wind action does not lift the geomembrane. The face anchorage of the geomembrane is carried out at points, by a patented system of deep anchors, grouted or earth anchor type, embedded in the compacted granular facing. The perimeter seals are designed to adapt to differential movements.

Applications: Embankment dams, Hardfill dams, Cofferdams, Reservoirs, Canals (low cohesion granular material)
  • Ensure stability on subgrades
    with low pull-out strength
  • Resists settlements
    and differential movements
  • Low environmental footprint

Covered geomembranes

When specific project design conditions require it, the geomembrane can be fixed to the structure by ballasting, installing a cover layer.

The following options are available:

  • concrete panels in which the geomembrane is embedded – for RCC dam facings
  • reinforced concrete for hydrotunnels, transport tunnels and shafts
  • granular materials for embankments.

In some cases, the cover layer is applied partially to sections that require it, or to fit a part of a structure of different design.

The design of the perimeter seals is site specific, the installation closely follows the construction schedule.

Covered geomembranes - Heavy and rigid covers

One of the possible ballasting solutions for reservoirs is a concrete cover. The concrete can be installed as reinforced slabs cast in situ, or as precast elements. These covers are often placed on a geotextile cushion.
  • Total protection
  • Proven technique
  • Can be used for partial covers

Covered geomembranes - Granular covers

Granular covers are used in embankments, either to ballast an upstream geomembrane, or to embed a geomembrane waterproofing barrier, placed in a central zigzag core, or as inclined upstream core A cushioning geotextile is placed on the geomembrane to protect it from puncturing.
  • Total protection
  • Environmentally friendly
  • Resist settlements
    and differential movements

Covered geomembranes - Heavy and rigid covers

One of the possible ballasting solutions for reservoirs is a concrete cover. The concrete can be installed as reinforced slabs cast in situ, or as precast elements. These covers are often placed on a geotextile cushion.
  • Total protection
  • Proven technique
  • Can be used for partial covers

Covered geomembranes - Granular covers

Granular covers are used in embankments, either to ballast an upstream geomembrane, or to embed a geomembrane waterproofing barrier, placed in a central zigzag core, or as inclined upstream core A cushioning geotextile is placed on the geomembrane to protect it from puncturing.
  • Total protection
  • Environmentally friendly
  • Resist settlements
    and differential movements

External water stops

External water stops

Traditional embedded water stops can fail due to insufficient elongation capacity or poor placement. Carpi's patented external water stop, with a highly deformable watertight geomembrane supported by appropriate geosynthetics, resists multiaxial movements of contiguous blocks and large differential movements at the deformable body/rigid concrete appurtenance interface.

Applications: Embankment dams, RCC dams, Pumped storage reservoirs, Reservoirs
  • Resist differential movements
  • No interference with
    the construction of the structure
  • Can be inspected at all times

External water stops

Traditional embedded water stops can fail due to insufficient elongation capacity or poor placement. Carpi's patented external water stop, with a highly deformable watertight geomembrane supported by appropriate geosynthetics, resists multiaxial movements of contiguous blocks and large differential movements at the deformable body/rigid concrete appurtenance interface.

Applications: Embankment dams, RCC dams, Pumped storage reservoirs, Reservoirs
  • Resist differential movements
  • No interference with
    the construction of the structure
  • Can be inspected at all times

Carpi, the Freyssinet's waterproofing specialist

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Carpi, the Freyssinet's waterproofing specialist

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