What is a Geosynthetic material?
 According to ASTM D4439, a geosynthetic is defined as follows: A planar product
manufactured from polymeric material used with soil, rock, earth, or other
geotechnical engineering related material as an integral part of a human-made project,
structure, or system
 In short it can be defined as a natural or artificial product that is used along with
geomaterials to in geotechnical engineering/construction

Why Geosynthetic materials?
 Geosynthetics have entirely changed the way geotechnical engineering is
practiced.
 Innovative solutions to solve difficult problems expediently
 They are invariably cost competitive against soils or other construction materials
 Wide variety of geosynthetic products are available to meet specific needs
 Enables the use of local materials – sustainable solutions
 Unskilled labor can be employed
 Installation does not require heavy machineries
 Carbon footprint is very much lower than traditional solution

Type of Geosynthetics
 Geotextile
 Geogrids
 Geonets
 Geomembranes
 Pre-fabricated vertical drain (PVD)
 Geosynthetic clay liners (GCL)
 Geocells
 Geocomposites
 Geomats
 Geopipes
 Geofoams

Geogrids
Geonets Geomembranes
Geotextile

Pre-fabricated vertical drains Geosynthetic clay liners
Geocells Geocomposite

Geomats Geopipes
Geofoams

Geotextile
 According to ASTM D4439, a geotextile is defined as, A permeable
geosynthetic comprised solely of textiles. Geotextile are used with
foundation, soil, rock, earth, or any other geotechnical engineering
related materials as an integral part of a human- made product,
structure, or system
 In short, Engineering sheet like products made of natural or synthetic
materials
Manufacture of Geotextile
Manufacturing of Geotextiles are mainly differentiated by the
 Polymer type
 Fiber type
 Manufacturing process

Polymers
 Geotextiles are generally made from synthetic fibers rather than natural
fibers.
 The synthetic materials or polymers are made in chemical processing
plants from the polymerization of thermoplastics.
 Short term and long term properties of geotextile depend on the polymer
that used to make the product
 Geotextiles are commonly made from the polymers of
 Polypropylene
 Polyester
 Polyethylene
 Polyamide

Fibers
 Fibers are made of polymers by drawing and stretching the melted
polymers through a narrow opening of spinneret –similar to shower head
 This fiber filaments are cooled and hardened -wet, dry or melt process
 Fibers are hard and strong compared to the raw polymer because of the
stretching process
 Stretching reduces fiber diameter and orients the molecules to gain higher
strength and stiffness
There are 4 main fiber types which are used to manufacture
woven geotextiles
 Monofilament
 Multifilament
 Slit-film monofilament
 Slit-film multifilament

Monofilament Multifilament

fiber types used to manufacture nonwoven geotextiles are
 Continuous filament fibers
 Staple fibers
Continuous filament fibers Staple fibers

Types of Geotextile
Yarns or fibers are made into textile in two methods
 Woven: Weave pattern is visible
Plain Weave : Common weave pattern, one up and one down
Basket weave : Tow or more warp and /or filling yarn used
Twill Weave :Diagonal weave pattern with yarn intersection one pick higher
Plain Weave Basket Weave Twill weave

Types of Geotextiles
 Non woven: Fibers are randomly oriented, no weave pattern is visible
Melt or heat bonded : Fibers are spread on a roller and joined by melting
at cross over point
Resin bonded : Fibers are bonded by spraying acrylic resin
Needle Punched : Fibers are entangled with each other to the form of
continuous fabric sheet
Melt or heat bonded Resin bonded Needle punched

Geotextile Types at a Glance

Function of Geotextile
 Separation
 Reinforcement
 Filtration
 Drainage
 Protection
 Erosion Control

Erosion Control
Embankment Protection

Testing of Geotextile
 Identification of product
 Selection of suitable materials as per design specification
 Quality control – during production stage
 Quality assurance – during the construction stage
 Maintaining smooth operation
 Performance checking at site condition

Properties of Geotextile
 Physical Properties
 Mechanical Properties
 Hydraulic Properties
 Endurance and Durability Properties

Geotextile - Mechanical properties
Following tests are conducted for determination of Mechanical properties
 Compressibility
 Tensile Strength
 Seam Strength
 Tear Strength
 Burst Strength
 Puncture Test
 Impact Test
 Pullout Test
 Frictional Behavior Test

Geotextile – Hydraulic properties
Following tests are conducted for determination of Hydraulic properties
 Apparent Opening Size
 Cross Plane Permeability
 In Plane Permeability
 Gradient Ratio
 Long Term Permeability

Geotextile – Endurance and Durability
properties
Following tests are conducted for determination of endurance and
durability properties
 Abrasion Resistance
 UV resistance
 Melt Flow Index
 Asphalt Retention

Function of Geotextile
Separation