geotextiles

Geotextiles are permeable fabrics used in civil engineering to improve soil performance. Made from synthetic polymers or natural fibers, they are placed in or on the ground to act as a physical separator, filtration layer, drainage medium, or reinforcement element. Their permeability allows water to pass while preventing soil movement, making them suitable for diverse earthwork projects.

Geotextiles are broadly categorized by construction: woven geotextiles, produced by interlacing fibers, and nonwoven geotextiles, formed by bonding or felting fibers. Woven geotextiles typically provide higher tensile strength and reinforcement, while nonwovens offer greater permeability and filtration capability. Materials commonly used include polypropylene and polyester for synthetic geotextiles, with natural options such as jute, coir, and sisal available for certain applications or sustainability goals.

Key functions include separation of different soil layers to prevent mixing, filtration to prevent soil movement while allowing water passage, drainage to collect and convey subsurface water, stabilization and reinforcement of weak soils, and erosion control on slopes or along channels. Typical uses include road and railway subgrades, earthworks in embankments, retaining walls and slope protection, drainage layers beneath pavements, landfill liners and covers, and coastal or riverbank protection.

Proper installation involves site preparation, correct geotextile selection to suit load and permeability requirements, overlapping seams, and protection from sharp objects during placement and compaction. Durability depends on material and exposure; synthetic geotextiles generally resist in-situ conditions for decades, while natural geotextiles may be less durable. Performance is governed by standards and tests that assess tensile strength, elongation, permeability, and aging; manufacturers provide product specifications and installation guidelines.