Geomembrane Protection


In tunnel constructions ALYAF geotextiles perform the dual function of protecting the tunnel liner from puncture damage as well as transmit water along the plane of the geotextile to the side drains.

The critical geotextile properties to be considered are :
  • puncture Strength
  • Tranmissivity
  • Mass per unit area
  • Thickness
Synthetic geomembrane liners are sensitive to mechanical damage and need protection to resist puncture and wear due to abrasion caused by sharp stones in the subgrade or the overlying layer. The effective puncture resistance of the geomembrane can be considerably increased by using appropriate ALYAF needle-punched nonwoven geotextile.

Below chart illustrates the results of puncture test using 400gsm needle-punched nonwoven geotextiles on geomembranes all 0.75 mm thick.

  • Increased puncture and abrasion resistance of the geomembrane.
  • Dissipation & lateral drainage of ground/seepage water that prevents the build-up of hydraulic pressure underneath the membrane.