Natural Geotextiles

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  • Topic: Geotechnical engineering, Fiber, Fibers
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Natural Fiber Geotextiles
Dr Muhammad Mushtaq Mangat www.mushtaqmangat.org

Natural Fiber Geotextiles





As old as human history Ziggurat in the ancient city of Dur-Kurigatzu (now known as Agar-Quf) The Babylonians 3000 years ago constructed this ziggurat using reeds in the form of woven mats and plaited ropes as reinforcement Great Wall of China The Great Wall of China, completed circa 200BC, utilized tamarisk branches to reinforce mixtures of clay and gravel




Modern application



The first use of a textile fabric structure for geotechnical engineering was in 1926, undertook a series of tests using woven cotton fabrics as a simple type of geotextile/ geomembrane, to help reduce cracking, ravelling and failures in roads construction [1].

  Highways Department in South Carolina USA

Woven mat and plaited rope reeds used as reinforcement in the Ziggurat at Dur Kurigatzu [1]

[1]

Vegetable fibers



Vegetable fibers contain a basic constituent, cellulose, which has the elements of an empirical formula (C6 H10 O5 )n .

  They can be classed morphologically, that is

according to the part of the plant from which they are obtained. [1]:



Bast or phloem fibres (often designated as soft fibres) are enclosed in the inner bast tissue or bark of the stem of the dicotyledonous plants, helping to hold the plant erect. the cellular and woody tissues, i.e. the plant stalks are rotted away from the fibres. Examples of the most common of these are flax, hemp and jute.

  Retting is employed to free the fibers from

hemp Ramie

Jute

Flax

Leaf fibres

  Leaf fibres (often designated as hard fibres) run

hawser-like within the leaves of monocotyledonous plants. of the leaves.

  These fibres are part of the fibrovascular system
  The fibres are extracted by scraping the pulp

from the fibres with a knife either manually or mechanically. Examples of these are abaca and sisal.

  Examples of these are abaca and sisal. [1]

ABACA

SISAL

Seed and fruit fibres



Seed and fruit fibres are produced by the plant, not to give structural support, but to serve as protection for the seed and fruit that are the most vulnerable parts of the plant normally attacked by predators. Examples of these are coir and cotton. With coir fiber, the coconut is de-husked then retted, enabling the fiber to be extracted.



Coir fibers

Natural fiber production



Of the 1000 to 2000 fibre-yielding plants throughout the world, there are some 15–25 plants that satisfy the criteria for commercial fibre exploitation although a number of these are only farmed on a small scale.

  These main fibres are flax, hemp, jute, kenaf, nettle, ramie, roselle, sunn, urena (bast fibres)

abaca, banana, cantala,date palm, henequen, New Zealand flax, pineapple, sisal, (leaf fibre) coir, cotton and kapok (seed/fruit fibres). [1]

Applications for natural geotextiles

  The use of geotextiles for short-term/

temporary applications to strengthen soil has a particular niche in geotechnical engineering. developed countries to combat numerous geotechnical engineering problems safely, efficiently and economically. [1]

  Geotextiles are used extensively in

Soil reinforcement



Soil is comparatively strong in compression, but very weak in tension. If a tensile inclusion (geotextile) is added to the soil and forms intimate contact with it, a composite material can be formed which has superior ngineering characteristics to soil alone.[1]



Mud and wheat straw used as plaster

Short-term embankments



Geotextiles provide an invaluable solution to the problem of constructing embankments over soft compressible ground where water fills the pores between the soil particles under the embankment. The load from the embankment fill increases the tendency for the embankment to fail. [1]



Filtration...
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