Geotextiles have been used for thousands of years. Geotextiles were used in roadway construction in the days of the Pharaohs to stabilise roadways and their edges. These early geotextiles were made of natural fibres, fabrics or vegetation mixed with soil to improve road quality, particularly when roadswere made on unstable soil. Only recently have geotextiles been used and evaluated for modern road construction.
Geotextiles is defined as any permeable textile material that is used with foundation, soil, rock, earth, etc to increase stability and decrease wind and water erosion. A geotextile may be made of synthetic or natural fibers. In contrast, a geomembrane is a continuous membrane-type liner or barrier Geomembranes must have sufficiently low permeability to control migration of fluid in a constructed project, structure or system. A geotextile is designed to be permeable to allow the flow of fluids through it or in it, and a geomembrane is designed to restrict the fluid flow.
Geotextile use will sometimes mask slope failures until erosion is too far advanced to effectively and cheaply remediate the slope. When advanced erosion is detected it means costly restoration. In contrast when a hydroseeded area has crust failure, whether from weather, human or animal activity, the damage is visible early and can be cheaply repaired.
Erosion control covers a variety of conditions from high velocity stream flow to heavy wave action, to less severe conditions.; All conditions should be considered before selecting a method of control.
Natural fibre geotextiles degrade to form an organic mulch and help in quick establishment of vegetation. Different fibres will degrade at different rates eg coir geotextiles degrade in 2-3 years while jute degrades in 1-2 years. Coir is therefore useful in situations where vegetation will take longer to establish, and jute is useful in low rainfall areas because it absorbs more moisture.
In many arid and semi-arid areas the action of the wind causes considerable erosion. Geotextiles made from natural fibre such as coir, or jute can be used for wind erosion control, dust control, sand dune formation and stabilization. Jute is particularly useful for dust control because of the hairiness of the fibres.
The properties of polymer material are affected by its average molecular weight (MW ) and its statistical distribution. Increasing the average MW results in increasing:
Narrowing the molecular weight distribution results in:
Geotextile use will sometimes mask slope failures until erosion is too far advanced to effectively and cheaply remediate the slope. When advanced erosion is detected it means costly restoration. In contrast when a hydroseeded area has crust failure, whether from weather, human or animal activity, the damage is visible early and can be cheaply repaired.
Erosion control covers a variety of conditions from high velocity stream flow to heavy wave action, to less severe conditions.; All conditions should be considered before selecting a method of control.
Natural fibre geotextiles degrade to form an organic mulch and help in quick establishment of vegetation. Different fibres will degrade at different rates eg coir geotextiles degrade in 2-3 years while jute degrades in 1-2 years. Coir is therefore useful in situations where vegetation will take longer to establish, and jute is useful in low rainfall areas because it absorbs more moisture.
In many arid and semi-arid areas the action of the wind causes considerable erosion. Geotextiles made from natural fibre such as coir, or jute can be used for wind erosion control, dust control, sand dune formation and stabilization. Jute is particularly useful for dust control because of the hairiness of the fibres.
The properties of polymer material are affected by its average molecular weight (MW ) and its statistical distribution. Increasing the average MW results in increasing:
- Tensile strength
- Elongation
- Impact strength
- Stress crack resistance
- Heat resistance
Narrowing the molecular weight distribution results in:
- Increased impact strength
- Decreased stress crack resistance
- Decreased processability
Increasing crystallinity results in:
- Increasing stiffness or hardness
- Increasing heat resistance
- Increasing tensile strength
- Increasing modulus
- Increasing chemical resistance
- Decreasing diffusive permeability
- Decreasing elongation or strain at failure
- Decreasing flexibility
- Decreasing impact strengthDecreasing stress crack resistance
In Technical Textile , geotextiles, industrial textile or medical textiles are main.
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