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DRAINTUBE T - Extrados drainage


Extrados drainage of underground structures such as cut and cover tunnels, limits the hydraulic head on the structure and prevents water infiltration.

Installed on the waterproofing system, DRAINTUBE T® combines the three functions: filtration, drainage and mechanical protection in a single product and a single installation. It replaces the protection geotextile, the drainage layer made of granular material, and the filtration geotextiles.

DRAINTUBE T® has a high and stable over time drainage capacity, even under heavy loads. This allows it to be used under high embankments.


  • High drainage capacity under heavy loads
  • Drainage of the groundwater
  • Mechanical protection of the waterproofing system
  • Improvement of the performance of the waterproofing system by limiting the hydraulic head on it
  • Easy installation with a single product to unroll
  • Cost-effective and environmentally friendly solution as it replaces granular layers


Drainage Drainage
Filtration Filtration
Mechanical protection Mechanical protection


  • Polypropylene geocomposite
  • Roll width : 3.90 m
  • Roll length : 50 m
  • 3 diameters of perforated mini-drains : 16 mm, 20 mm and 25 mm
  • 4 possible distances between mini-drains : 200 cm, 100 cm, 50 cm and 25 cm