The Ultimate Guide to Understanding Geotextiles

What is Geotextile? An Overview:

Geosynthetics are now a standard part of civil engineering, and Geotextiles are the most widely used of them. They give predictable performance, are easy to install, and in many jobs replace graded soil filters, thicker aggregate layers or soil replacement.

Geotextiles are permeable fabrics, usually made of polyester or polypropylene. Their small pores let water and gases pass through while holding soil back. They are durable in the ground and stand up to harsh site conditions.

They are used so widely because they are strong, need little maintenance, install quickly and resist weathering when covered.

Types of Geotextiles:

Depending on the application, geotextiles are made of natural or synthetic fibres. Natural geotextiles are made of jute or coir and are used where the fabric should biodegrade, for example in erosion control until vegetation takes hold. Synthetic geotextiles are made mostly of polypropylene (PP) or polyester (PET), and less often of polyethylene (PE) or polyamide (PA).

Difference between woven and nonwoven Geotextiles:

Geotextiles are either woven or nonwoven. Woven geotextiles are made by weaving individual threads, monofilaments, slit-film tapes or fibrillated yarns on a loom at right angles, which gives a uniform, strong fabric.

Nonwoven geotextiles are made by bonding fibres together by chemical, thermal or mechanical (needle-punching) methods.

Functions and applications of Geotextiles:

Geotextiles are used in many applications: roads, parking areas, construction sites, railways, harbours, drainage works, breakwaters and hillside erosion control.

They do six jobs: separation, stabilization, filtration, reinforcement, moisture barrier (waterproofing) and drainage.

• Separation: the geotextile keeps two layers of different materials apart so they do not mix.
  Applications: road sub-bases, railway ballast, breakwaters, and between drainage stone and soil or waste in landfills.
• Stabilization: the geotextile is laid on soft, compressible ground under the fill, spreading the load and keeping the fill from punching into the soft layer.
• Reinforcement: a high-strength geotextile is placed within or under a weak soil mass to carry tension and strengthen it.
• Applications for stabilization and reinforcement: steep slopes, retaining walls, erosion control on lake and sea embankments, breakwaters, land reclamation with hydraulic fill, embankments on compressible soil, and slope and roadbed reinforcement.
• Filtration: the geotextile lets water pass through while holding back the soil particles the water would otherwise carry.
  Applications: road drainage, basement drainage and landfill drainage.
• Moisture Barrier: here the geotextile is meant to block water rather than pass it. It is impregnated with asphalt or bitumen emulsion, which makes it impermeable.
  Applications: canal lining and road pavement interlayers.
• Drainage: a geotextile wrapped around drain pipes and gravel keeps soil out of them, so they don’t clog and keep working longer.
  Applications: French drains, vertical drains, agricultural pipe drains, blanket drains in roads and sports fields, side drains and wall drains.

At Ocean Global, we supply woven and nonwoven geotextiles in a wide range of grades, along with our other Geosynthetics products . Reach out to us with your project details and we will suggest the right grade.