Waterproofing Function (Moisture barrier)
Geotextile can act as waterproof materials when impregnated with bitumen or polymeric sealing materials . After impregnation , the water and vapor permeability of the fabric become very low in both cross-plane and in plane-flow.
In a variety of structures, geotextiles are used with geomembranes. Geotextile can provide long term protection of geomembranes against mechanical damage ,such as perforation and abrasion ,during and after installation .Although in many applications it is possible to identify one dominate function out of these basic functions , often other functions still perform essential roles even if they are secondary . For instance , in an unpaved road base the role of a geotextile is clearly that of a separator . However , reinforcement and filtration Functions should also be considered .