AGRUFlex® Tunnel Lining System from AGRU America


AGRU America’s AGRUFlex® Tunnel Liner protects concrete tunnel structures against the infiltration of water, aggressive soils, and root penetration. This tunnel lining system offers superior water resistance, reducing the maintenance costs of having to repair water spots, dripstones from lime diffusion, and external corrosion.

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Water does not have to be a major obstacle during tunnel construction. With AGRU’s complete tunnel lining system, you can expect superior water resistance that virtually eliminates the maintenance cost to repair water spots, dripstones from lime diffusion, and external corrosion. AGRUFlex, an integral part of our lining system, is the perfect partner in SEM/NATM or conventional bored tunnel constructions. Its primary purpose is to protect concrete tunnel structures against the infiltration of water and/or gases, and aggressive soils and groundwater. AGRU tunnel lining systems use high-grade resins made with advanced polyolefins, giving AGRUFlex its highly flexible mechanical properties, a long service life, and ease of installation. In addition, polyethylene does not produce toxic fumes which could cause health and safety concerns in the confined space of tunnel environs.

AGRU’s tunnel waterproofing liners are perfectly suited for any type of tunnel construction including cut-and-cover, drill-and-blast (SEM/NATM), and TBM bored methods. AGRUFlex is the preferred waterproofing liner system for all types of tunnel applications including highway, rail, light rail, hydro, and more.

Underground Stations

Underground stations, caverns, and cross-passages need many of the same concrete protection as the connecting tunnels. AGRUFlex serves as the primary liner against corrosion and water penetration in these applications as well.

Waterproofing Monolithic Systems

Water stop profiles give the necessary redundancy in waterproofing tunnels throughout the lifetime of the construction. Modern tunnel lining is designed to support discrete repairs of hollow or leaky areas through the use of injection grouts. Water stop profiles are installed between the liner and concrete to create separate compartments. Integrated injection hoses can then be used to inject grout at repair

AGRUFlex is created from high-grade resins of quality raw material. The manufacturing process yields a highly flexible tunnel lining material that is easy to install and weld. No toxic fumes are produced should AGRUFlex come into contact with a chemical or electrical fire. And its high-quality construction and EasyFix system ensures maximum service life.

Efficient waterproofing in tunnels

AGRUFlex is manufactured from very low density polyethylene and supports:

Signal layer advantages

AGRU coextrudes AGRUFlex with a white/colored signal layer.

Advanced installation methods

AGRUFlex supports innovative insulation technologies, with benefits such as:

One-stop shopping

Purchase liners, water stop profiles, attachment discs, and drainage pipes from under one roof.


EasyFix delivers fast and reliable installation of VLDPE fabric backed tunnel liners.

  • No influence of the liner‘s mechanical properties caused by adhesive bonding
  • Installation with semi-automatic formworks
  • Flexible installation methods
  • Up to 40% reduction in installation time with easy and precise placement of the tunnel liner
  • Liner widths up to 4m

AGRU Waterstop Profiles

The perfect solution for attaching the liners and concrete protective liners to concrete constructions and compartmentalizing areas in case of future repairs.

  • Integrated injection hose clamp for OD 9 – 12 mm
  • Defined outlets for even distribution
  • Polyolefin based VLDPE resin
  • Optimized compatibility with polyolefin based tunnel liners
  • Free of plasticisers and halogens
  • Brochure
  • Lining Systems
Data Sheets
  • AGRUFlex® Data Sheet
  • Water Stop Profile Data Sheet
  • AGRU Tunnel Mounting Disc Data Sheet

Need Help Determining Which Product is Right For Your Application?

Interested in learning more about how one of our products can make a difference in your next project? Please reach out to us with your questions and one of our sales or technical staff will be happy to assist you.

We can help you determine your exact product or application-related needs. And because our products meet, and often exceed, industry standards you can rest assured knowing that you are getting the best solutions in the business.