There are many applications for the use of geotextiles. The primary uses are:
(+1) Cushioning – effective and low-cost protection to membrane from damage by sharp objects.
(2) Drainage – allows subsurface water to pass to drain system while preventing soil from clogging system.
(3) Separation – applied to soft or saturated subgrade, prevents aggregate and ballast from mixing into subgrade.
(4) Filtration – geotextiles can provide collection and transfer of liquids and gases that build up and accumulate beneath geomembranes.
(5) Reinforcement – geotextiles can help relieve hydrostatic pressure beneath hard armor such as highways.
The two major classifications are woven and non-woven. Woven geotextiles have high tensile strength and low elongation, while non-woven geotextiles have high permeability and high conformability because of their high elongation characteristics.