It will use for civil students to learn easily

1. What are Geosynthetics?
GEO
 Soil, Rock or other Geotechnical material
SYNTHETIC
 Man made
 Polymeric material
Used to enhance, augment and make
possible cost effective construction

2. Polymer - Types & Materials
Polypropylene(PP)
Polyethylene (HDPE, LDPE, LLDPE)
Polystyrene (PS)
Polyvinyl Chloride (PVC)
Polyamide (PA) eg. Nylon
Polyester
Acrylonitrile Butadiene Styrene (ABS)

3. Roles or Functions of
Geosynthetics
 Separator
 Reinforcement
 Drainage
 Filter
 Energy absorber
 Container
 Barrier

4. Geosynthetic Global Offer

5. Types of Geosynthetics
Geotextiles (GT)
Geogrids (GG)
Geonets (GN)
Geomembranes (GM)
Geosynthetic clay liners (GCL)
Geocomposites (GC)
Geo others
 Geopipe, Geofoam, Geocells, Geomesh

6. Geotextiles (GT)

7. Geotextiles (GT)
Flexible, textile-like fabrics
Majority are made from polypropylene fibers
Woven (slit film, monofilament or multifilament)
Nonwoven (needle punched or heat/chemical bonded)
Characterised by an open and porous structure
(with controlled permeability)
Mechanical and Hydraulic properties vary widely
Very versatile in their primary function
(except as liquid barrier)

8. Geogrids (GG)

9. Geogrids (GG)
stiff or flexible polymer grid-like sheets
structure allows for soil “strike-through”
bidirectional – equal strength in both directions
unidirectional – main strength in machine
direction
focuses entirely on reinforcement applications,
e.g.,walls, steep slopes, base and foundation
reinforcement

10. Geonets (GN)

11. Geonets (GN)
all are made from high density polyethylene
results in parallel sets of ribs as a integral unit
biplanar – flow is equal in all directions
triplanar – flow much greater in machine
direction
function is always in-plane drainage
surfaces must be covered; usually with GTs

12. Geomembranes (GM)

13. Geomembranes (GM)
impermeable sheets (10-11 to 10-13 cm/s)
function is always containment
represents a barrier to liquids and gases
many types: HDPE, LLDPE, fPP, PVC,
EPDM, etc.
manufactured rolls are field seamed
new applications in hydraulics and private
development

14. Geosynthetic Clay Liners (GCL)

15. function is always containment
common product is bentonite between 2-GTs
internally reinforced by needle punched or
stitching
bentonite product bonded to GM is also available
many other variations exist
competitive with compacted clay liners (CCLs)
beneath a GM; one has a composite liner
Geosynthetic Clay Liners (GCL)

16. Geopipe (GP)
GEOPIPE

17. Geopipe (GP)
its really buried plastic pipe!
function is always drainage
HDPE and PVC most common
can be smooth walled or corrugated
corrugated HDPE growth is enormous

18. Geofoam (GF)
GEOFOAM

19. Geofoam (GF)
lightweight fill on soft or sensitive soils
relieves lateral pressure on walls
also used for insulation of frost-sensitive
soils

20. Geocomposites (GC)

21. Geocomposites (GC)
hybrid systems of any or all
array of available products
GT/GM; GT/GG; GT/GN; etc.
considerable ongoing innovation
primary function depends on final product

22. Function vs. Geosynthetic Type
Type of
Geosynthetic
Separation Reinforcement Filtration Drainage Containment
geotextile    
geogrid 
geonet 
geomembrane 
geosynthetic
clay liner

geopipe 
geofoam 
geocomposite     

23. Properties of Geosynthetics -
Parameters
Physical
Chemical
Mechanical
Hydraulic
Endurance
Degradation

24. Physical
 Thickness
 Specific Gravity
 Mass per unit area
 Porosity
 Percent open area
 Apparent opening size
Parameters . . . .

25. Chemical
 Polymer type
 Filler material
 Carbon black percentage
 Plasticizers and additives
 Manufacturing process
Parameters . . . .

26. Mechanical
 Tensile strength
 Compressibility
 Elongation
 Tear/impact/puncture resistance
 Burst strength
 Seam strength
 Fatigue resistance
 Interface friction with soil
 Anchorage in soil
Parameters . . . .

27. Hydraulic
 Permittivity (cross plane permeability)
 Transmissivity (in plane permeability)
 Clogging potential
Parameters . . . .

28. Endurance
 Installation damage potential
 Tear/impact/puncture resistance
 Abrasion resistance
 creep
Parameters . . . .

29. Degradation
Resistance against
 Ultraviolet radiation
 Temperature
 Oxidation
 Aging
 Chemical and Biological reactions
Parameters . . . .

30. Properties of Geosynthetics
Range of Values
Type
Thickness
(mm)
Mass per
unit area
(gsm)
Tensile
strength
(kN/m)
Elongation
(%)
Apparent
opening size
(mm)
Non-Woven
Geotextile
0.25 – 7.5 100 – 2000 5 – 100 20 – 100 0.02 – 0.6
Woven
Geotextile
0.25 – 3.0 100 – 1500 20 – 400 10 – 50 0.05 – 2.0
Geomebranes 0.25 – 3.0 250 – 3000 10 – 50 50 – 200 ~ 0
Geogrids 5.0 – 15.0 200 – 1500 10 – 200 5 – 25 10 – 100
Geonets 3.0 – 10.0 100 – 1000 – – 5 – 15

31. Separation
 High tensile strength (20 – 400 kN/m)
 Allow flow of water but no mixing of soil
 High burst strength
 High tear/impact/puncture resistance
Geotextiles (usually woven)
Functional requirements

32. Filtration
 Cross-plane permeability higher than base soil
(10e-5 to 1 m/s)
 Pore size small enough to enable retention of fines
(95% pore size – 0.02 to 2.0 mm)
 Low clogging potential
Geotextiles (usually non-woven)
Functional requirements . . . .

33. Drainage
 Requirements of filtration
 High in-plane permeability
Geotextiles (thick non-woven)
Geonets sandwiched b/w geotextiles
(Geocomposite sheet drain)
Functional requirements . . . .

34. Reinforcement
 High tensile strength
 Low elongation (high stiffness) (5 to 25%)
 High shearing resistance along soil
reinforcement interface
Geotextiles (low elongation)
Geogrids
Functional requirements . . . .

35. Barrier
 High imperviousness (10e-12 to 10e-15 m/s)
 Leakproof welding along seams
 No slippage when laid along sloping ground
Geomebranes
Functional requirements . . . .