What is
Geotextile?:
Geotextiles are polymer fabrics used in the construction of
roads, drains, harbour works, and breakwaters,and for land reclamation and many
other civil engineering purposes.
Geotextiles, a newly emerging field in the civil engineering and other fields,
offer great potential in varied areas of applications globally.
Types
of Geotextile:
Geotextiles are a permeable synthetic material made of textile materials. They
are usually made from polymers such as polyester or polypropylene. The geotextiles
are further prepared in three different categories – woven fabrics, non-woven
fabrics and knitted fabrics.
Woven Fabrics:
Large numbers of geosynthetics are of woven type, which can be sub-divided into
several categories based upon their method of manufacture. These were the first
to be developed from the synthetic fibers. As their name implies, they are
manufactured by adopting techniques which are similar to weaving usual clothing
textiles. This type has the characteristic appearance of two sets of parallel
threads or yarns --.the yarn running along the length is called warp and the
one perpendicular is called weft.
Woven fabric
The majority of low to medium strength woven geosynthetics
are manufactured from polypropylene which can be in the form of extruded tape,
silt film, monofilament or multifilament. Often a combination of yarn types is
used in the warp and weft directions to optimize the performance/cost. Higher permeability
is obtained with monofilament and multifilament than with flat construction
only.
Non-woven:
Non
woven geo-synthetics can be manufactured from either short staple fibre or
continuous filament yarn. The fibers can be bonded together by adopting
thermal, chemical or mechanical techniques or a combination of techniques. The
type of fibre (staple or continuous) used has very little effect on the
properties of the non – woven geo synthetics. Non-woven geotextiles are
manufactured through a process of mechanical interlocking or chemical or
thermal bonding of fibres/filaments. Thermally bonded non-wovens contain wide
range of opening sizes and a typical thickness of about 0.5-1 mm while
chemically bonded non-wovens are comparatively thick usually in the order of 3
mm. On the other hand mechanically bonded non-wovens have a typical thickness
in the range of 2-5 mm and also tend to be comparatively heavy because a large
quantity of polymer filament is required to provide sufficient number of
entangled filament cross wires for adequate bonding.
Nonwoven
Knitted
Fabrics:
Knitted geosynthetics are manufactured using another
process which is adopted from the clothing textiles industry, namely that of
knitting. In this process interlocking a series of loops of yarn together is
made. An example of a knitted fabric is illustrated in figure. Only a very few
knitted types are produced. All of the knitted geosynthetics are formed by
using the knitting technique in conjunction with some other method of
geosynthetics manufacture, such as weaving.
Knitted fabric
Apart from these three main types of geotextiles, other
geosynthetics used are geonets, geogrids, geo-cells, geo membranes, geo
composites, etc. each having its own distinct features and used for special
applications.
What is
Geotextile?:
Types
of Geotextile:
Geotextiles are a permeable synthetic material made of textile materials. They
are usually made from polymers such as polyester or polypropylene. The geotextiles
are further prepared in three different categories – woven fabrics, non-woven
fabrics and knitted fabrics.
Woven Fabrics:
Large numbers of geosynthetics are of woven type, which can be sub-divided into
several categories based upon their method of manufacture. These were the first
to be developed from the synthetic fibers. As their name implies, they are
manufactured by adopting techniques which are similar to weaving usual clothing
textiles. This type has the characteristic appearance of two sets of parallel
threads or yarns --.the yarn running along the length is called warp and the
one perpendicular is called weft.
Woven fabric
|
Non-woven:
Non
woven geo-synthetics can be manufactured from either short staple fibre or
continuous filament yarn. The fibers can be bonded together by adopting
thermal, chemical or mechanical techniques or a combination of techniques. The
type of fibre (staple or continuous) used has very little effect on the
properties of the non – woven geo synthetics. Non-woven geotextiles are
manufactured through a process of mechanical interlocking or chemical or
thermal bonding of fibres/filaments. Thermally bonded non-wovens contain wide
range of opening sizes and a typical thickness of about 0.5-1 mm while
chemically bonded non-wovens are comparatively thick usually in the order of 3
mm. On the other hand mechanically bonded non-wovens have a typical thickness
in the range of 2-5 mm and also tend to be comparatively heavy because a large
quantity of polymer filament is required to provide sufficient number of
entangled filament cross wires for adequate bonding.
Nonwoven
|
Knitted
Fabrics:
Knitted geosynthetics are manufactured using another
process which is adopted from the clothing textiles industry, namely that of
knitting. In this process interlocking a series of loops of yarn together is
made. An example of a knitted fabric is illustrated in figure. Only a very few
knitted types are produced. All of the knitted geosynthetics are formed by
using the knitting technique in conjunction with some other method of
geosynthetics manufacture, such as weaving.
Knitted fabric
|
