Geotextiles let water through while holding soil back, which is what separates them from geomembranes. Woven types, mostly slit-film or monofilament polypropylene, carry high tensile loads at low stretch, while needlepunched nonwovens offer thickness, high flow and puncture cushioning. Products are compared on property tables built from index tests such as grab tensile, puncture, AOS and permittivity.
Spec calls for a Class 2 nonwoven geotextile under the riprap, so the 4-ounce on that truck won't pass.
Check the roll labels against the approved submittal before any wrap comes off; returns are easy until a roll has been opened.
Also heard as
- fabric
- filter fabric
- geofabric
Related terms
Nonwoven geotextile
Geotextile made by needlepunching or heat-bonding fibers into a felt-like sheet, used for filtration, drainage and cushioning.
Slit film
Woven geotextile made from flat polypropylene tapes cut from extruded film, strong and cheap but a poor filter.
Monofilament woven
Woven geotextile of round single-strand yarns that leaves regular open pores for high flow and good filtration.
Separation
Keeping two different soil layers, such as an aggregate base and a soft subgrade, from mixing under load.
Filtration
Letting water pass across a geotextile while holding back the soil particles it carries.