TRAINING WORKSHOP ON NON-WOVENS IN GEOTEXTILES

AT SURAT

BY

S.K. PURI

CHIEF GENERAL MANAGER - NHAI

5TH MARCH 2008

National Highways

• Total Length of NHs : 65,569 km (2% of total road length)

• Roads carry 85% of Passenger and 70% of Freight Traffic

• NHs carry about 40% of traffic • NHAI is entrusted with implementation of

National Highways Development Project (NHDP)

Components of NHDPPhase Length (Km) Cost

(Rs crore)Focus

I Bal. 1738 Bal. 9071 Golden quadrilateral (GQ)- connecting Delhi-Mumbai-Chennai- Kolkata-Delhi Total Length 5846

II Bal. 6736 Bal. 43623 North South& East west Corridors (NS-EW) Total Length 7300

III 12,109 80,626 State capital connectivity,High traffic density, Imp.centers of tourism &economic activity

IV 20,000 27,800 Widening & Strengthening to 2-lane with Paved shoulders

V 6,500 41,210 Six laning of high density corridors

VI 1000 Km 16,680 Expressway for connecting important places

VII (Being identified) 16,680 Ring roads to cities, flyovers, by-passes

SARDP-NE 588 5208 Special Accelerated Road Development Programme for NE

ICTT Cochin

17 557 International Container Transhipment Terminal

Total 48,688 2,41,454

Definition, Type, Process and PropertiesDefinition, Type, Process and Properties

Any permeable textile natural or synthetic, used with foundation Any permeable textile natural or synthetic, used with foundation soil, rock, earth, or any other geotechnical engineering related soil, rock, earth, or any other geotechnical engineering related material.material.

What is a Geotextile?What is a Geotextile?

Types of Geotextile

Woven Non-woven

Method of production Process Form of fibre Polymer

PP/PE bi-componentContinuous filament PP

Heat-bondedStaple fibre

PPPP/PE mix

NonwovensPPPET

Staple fibre HDPENeedle-punched

Continuous filament PPPET

Nonwoven GeotextilesNonwoven Geotextiles

Needle Punched nonwoven

Thermally bonded nonwoven

Nonwoven GeotextilesNonwoven Geotextiles

Method of production Process Form of fibre Polymer

Slit-flat tape PP (HDPE)Wide loom (beam) Fibrillated yarn PP

Wide loom (creel) Multi-filament yarn PET (PA)Woven

<3.8m loom (beam)Medium mono filament

with yarnPP

HDPEPA

Woven GeotextilesWoven Geotextiles

Slit film tape-on-slit film tape

Extruded tape-on-extruded tape

Woven GeotextilesWoven Geotextiles

Monofil woven fabric

PET multifilament woven fabric

Woven GeotextilesWoven Geotextiles

Method of production Process Form of fibre Polymer

Stitched-bondedNonwoven base with multi-

filament stitch yarnPP or PET nonwoven

PET stitching

Knitted Weft insertion filament yarn PET

Warp knitted Multi-filament yarn PET

Knitted GeotextilesKnitted Geotextiles

Knitted base

Upper surface

Knitted GeotextilesKnitted Geotextiles

Physical Properties

Property Value range

Specific gravity 0.9 – 1.7

Mass per unit area 135 – 1000 g/m3

Thickness 0.25 – 7.5 mm

Stiffness Nil – 25,000 mg-cm

Mechanical PropertiesProperty Value Range

Compressibility Nil to high

Tensile strength (grab) 0.45-4.5 kN

Tensile strength ( wide width) 9-180 kN/m

Confined tensile strength 18-180 kN/m

Seam strength 50-100% of tensile

Cycle fatigue strength 50-100% of tensile

Burst strength 350-5200 k Pa

Tear strength 90-1300 N

Impact strength 14-200 J

Puncture strength 45-450 N

Friction behavior 60-100% of soil friction

Pullout behavior 50-100% of geotextile strength

Hydraulic PropertiesProperty Value Range

Porosity (non wovens) 50-95%

Present open area (wovens) Nil to 36%

Apparent opening size ( sieve size)

2.0 to 0.075 mm ( # 10 to # 200)

Permittivity 0.02-2.2s-1

Permittivity under load 0,01-3.0s-1

Transmissivity 0.01 to 2.0 x10-3m2/min

Soil retention: turbidity curtains Must be evaluated

Soil retention: silt fences Must be evaluated

Endurance PropertiesProperty Value Range

Installation damage 0.70% of fabric strength

Creep response g.n.p.if <40% strength is being used

Confined creep response g.n.p.if <50% strength is being used

Stress relaxation g.n.p.if <40% strength is being used

Abrasion 50-100% of geotextile strength

Long-term clogging m.b.e.for critical conditions

Gradient ratio clogging m.b.e. for critical conditions

Hydraulic conductivity ratio 0.4-0.8 appear to be acceptable

g.n.p. – generally no problem, m.b.e. – must be evaluated

Degradation PropertiesProperty Value Range

Temperature degradation High temperature accelerates degradation

Oxidative degradation m.b.e. for long service lifetimes

Hydrolysis degradation m.b.c. for long service lifetimes

Chemical degradation g.n.p.unless aggressive chemicals

Radioactive degradation g.n.p.

Biological degradation g.n.p.

Sunlight ( UV) degradation Major problem unless protected

Synergistic effects m.b.e.

General aging Actual record to date is excellent

TYPICAL PHYSICAL PROPERTIES OF GEOTEXTILESTYPICAL PHYSICAL PROPERTIES OF GEOTEXTILES

Function Strength range kN per m

Mass per unit area gm per sq m

Roll width Metre

Roll length Metre

Separation 0.5 – 5 70 - 500 3.8 to 5.5 (4.5) 50 to100

Filtration 0.3 – 2 70 - 250 2.5 to 4.5 50 to100

Drainage 1 – 5 500 - 2000 1.5 to 5.5 25 to 50

Reinforcement 30 - 1000 N/A 3.8 to 5.5 or strips

50 to100 or Defined

DENSITY MELTING STRAIN CREEP UNITS

POLYMER

g/cm3 ºC % CREEP PE, PP 0.90 to 0.95 110 to 170 >100 HIGH PET 1.38 >240 10 to 15 LOW

The polymers used for GeotextileThe polymers used for Geotextile

Abbreviation:

PE: Polyethylene

PP: Polypropylene

PET: Polyester

EN 12447

Geotextiles and geotextile-related products - Screening test method for determining the resistance to hhyyddrroollyyssiiss in water

EN 12226

Geotextiles and geotextile-related products - General tests for eevvaalluuaattiioonn following durability testing

EN 14030

(ISO 12960)

Geotextiles and geotextile-related products -Screening test method for determining the resistance to aacciidd aanndd aallkkaalliinnee liquids

EN ISO 13438

Geotextiles and geotextile-related products - Screening test method for determining the resistance to ooxxiiddaattiioonn at elevated oxygen pressure

EN ISO 12225

Geotextiles and geotextile-related products - MMiiccrroobbiioollooggiiccaall resistance (soil burial)

Durability Test MethodsDurability Test Methods for Geotextile for Geotextile

Functions and properties of GeotextilesFunctions and properties of Geotextiles

The functions of GeotextilesThe functions of Geotextiles

Separator

Reinforcement

Drainage

Filter

Energy absorber

Container

Reservoirs, damsReservoirs, dams

Liquid wasteLiquid waste Solid wasteSolid waste

RoadsRoads RailroadsRailroads

Erosion protectionErosion protection

Retaining wallsRetaining walls

Drainage systemsDrainage systems

APPLICATIONS FOR GEOTEXTILESAPPLICATIONS FOR GEOTEXTILES

1 ROADS 1.1 APPLICATIONS IN FILTRATION AND DRAINAGE

Pavement drainsSub-horizontal drainsCurtainsTrenchesSettlement acceleration

applications

materialsGeotextilesGeocomposite drain(PVD)

1 ROADS 1.2 APPLICATIONS IN EROSION CONTROL

MATERIALS

GEOTEXTILES

Detain carried particles: during construction, before vegetation or under wind effects

SUPERFICIAL EROSION

silt fences

1 ROADS 1.3 APPLICATIONS AS BARRIER

MEMBRANE-ENCAPSULATED SOILS - moisture barrier maintenance of base material properties

for use inlow cost pavements

in:wet regionsexpansive claysgood base soils (lateritic soils,..)

Materials asphalt impregnated geotextiles reinforced geomembranes geogrids (when hard cracking)

1 ROADS 1.4 SEPARATION AND REINFORCEMENT MATERIALS

SEPARATION GEOTEXTILES GEOCOMPOSITESREINFORCEMENT GEOGRIDS GEOTEXTILES GEOSTRIPS

2 BENEFITS OF GEOSYNTHETIC SEPARATORS2.1 TYPICAL APPLICATIONS

-prevent contamination-avoid build-up of pore pressure-avoid loss of granular material

Located at the interface between soil and aggregate

sub-base/sub-grade interfacesembankments

2 BENEFITS OF GEOSYNTHETIC SEPARATORS2.2 MECHANISMS

Avoid granular material penetration Puncture resistance

FiltrationPore size and permeability

Interlock advantages Tensile resistance

3 BENEFITS OF GEOSYNTHETIC REINFORCEMENT

3.1 PAVEMENT SYSTEMS

3.1.1 ASPHALT OVERLAY

3.1.2 BASE/SUBGRADE

3.2 EMBANKMENTS OVER SOFT SOILS

3.3 SLOPES AND WALLS

3.1 PAVEMENT SYSTEMS 3.1.1 ASPHALT REINFORCEMENT

new roads

maintenance of existing roads

Increase in fatigue lifeReduction in rutting

3.1 PAVEMENT SYSTEMS 3.1.1 ASPHALT REINFORCEMENT

MECHANISMS GEOTEXTILE

GEOGRID

WITHOUT REINFORCEMENT

3.1 PAVEMENT SYSTEMS 3.1.1 ASPHALT REINFORCEMENT

thin nonwoven geotextiles can be used when cracking still keeps the aggregates interlocking

(tensile characteristics are not required)

protector layer - retards crack propagation by deviationmoisture barrier – increases life time after cracking

Note:

The asphalt impregnated geotextile do not acts as a reinforcement, but as a protector layer and a moisture barrier.

3.1 PAVEMENT SYSTEMS 3.1.2 SOIL STABILIZATION

“The use of a geosynthetic placed at the sub-grade/fill interface to increase thesupport of construction equipment over a weak or soft sub-grade”

Applications Temporary roadways Initial construction lift of permanent ways or embankments Area constructions platforms

3.1 PAVEMENT SYSTEMS3.1.3 BASE AND SUB-BASE REINFORCEMENT

The use of a geosynthetic placed as a tensile element at the bottom or within a flexible pavement base or sub-base to:

-increase the service life -obtain equivalent performance with a reduced structural section-avoid subsidence problems (sinkholes)

ApplicationsPermanents waysParking lotsAirport taxiwaysContainer loading facilitiesRailway tracks

3.1 PAVEMENT SYSTEMS 3.1.4 ADVANTAGES

-cost savings in construction and maintenance

-increase of service life

-decrease or eliminate over-excavation and required granular fill

“in pavements systems, life cycle cost analysis are important

to show additional maintenance cost savings”

3.2 EMBANKMENTS OVER SOFT SOIL3.2.1 Applications

-basal reinforcement-piled embankments with basal reinforcement-reinforcement over areas prone to subsidence

3.2 EMBANKMENTS OVER SOFT SOIL3.2.2 Basal reinforcement mechanisms

foundation extrusion

bearing capacity

rotational stability

3.2 EMBANKMENTS OVER SOFT SOIL3.2.3 Piled embankments basal reinforcement design

Ultimate limit statesPile group capacityPile group extentVertical loading sheddingLateral slidingOverall stability

Serviceability analysisReinforcement strainFoundation settlement

3.2 EMBANKMENTS OVER SOFT SOIL3.2.4 Construction

3.3 REINFORCED SLOPES AND WALLS3.3.1 applications

landslide reparationbridge abutmentincrease working areareduce filled area reduce filling material

3.3 REINFORCED SLOPES AND WALLS3.3.2 types

Walls (angle of inclination larger than 80o)

Steep slopes

Block walls

.

reinforcement spacing

3.3 REINFORCED SLOPES AND WALLS3.3.2 types

3.3 REINFORCED SLOPES AND WALLS3.3.3 benefits

Economical solutions

Rapid and simple construction method

Allows construction in difficult terrain

Allows use of cheaper fill material

Satisfactory appearance structures

Environmental:

reduce damaged areas and

reduce natural material extracting

4. REQUIREMENTS AND TECHNICAL PROPERTIES

Mainly mechanical characteristics

Tensile strength (ISO 10319)Seam tensile strength (ISO 10321)Puncture resistance (ISO 12236)Impact test (ISO 13433)

Mainly hydraulic characteristics (for separation)Opening size (ISO 12959)Permeability normal to the plane (ISO 11058)

Technical Requirement as per MoSRTH Specifications for use in subsurface drains

• Breaking load not less than 10 kN/m • Minimum Failure strain of 10%• Apparent opening size 0.22mm – 0.43 as

soil properties• Allow water flow @ not less than

10lit/sqm/sec• Minimum puncture resistance of 200 N• Minimum tear resistance of 150N

Technical Requirement as per MoSRTH Specifications for use in Highway Pavement

• Minimum Tensile strength 36.3 Kg

• Elongation 50%

• Asphalt Retention 10 kg/10sqm

• Melting Point 150C

• Surface Texture- heat Bonded on one side only

Technical Requirement as per MoSRTH Specifications for use in Protection Works

• Aperture : Rectangular, square or oval

• Colour : Black

• Strength : Min 10kN/m

• Elongation: Max 15%

• Form : GR1-GG3 standards

• Life : Min 8 years

Typical Specification of NHAISeparation and drainage

Properties Units Fabric

PHYSICAL

Grab Tensile Strength KN 0.900

Grab Tensile Elongation % 50

Mullen Burst KPA 2750

Puncture KN 0.575

Trapezoid Tear KN 0.355

UV Resistance %@hr 70/500

HYDRAULIC

Apparent Opening Size (AOS) Mm 0.150

Permittivity Sec 1.5

Flow Rate 1/min/m2 3225

Life Period Years 120

MINIMUM AVERAGE ROLL VALUES

Typical Specification of NHAISoil Reinforcement

Sl. No.

Minimum Partial FOS for calculation of 100 years long term design strength (TD) in accordance with BS-8006:1995 requirements

Woven PP based geotextiles

Woven PET based geotextiles

1 Partial FOS for deformation (at 40 C to meet less than 0.5% post construction strain requirement for retaining wall cases)

6.0 3.0

2 Partial FOS for variations in manufacture from control specimens (fm 11)

1.0 (use only MARV)

1.0 (use only MARV)

3 Partial FOS for extrapolation of creep test data (fm 12)

1.10 (10000 hours creep)

1.10 (10000 hours creep)

4 Partial FOS for construction/ installation damage (susceptibility to damage) [fm 21]

1.83 2.44

5 Partial FOS for potential chemical (at 40 C) and biological degradation. (Environment) [fm 22]

1.10 1.15

Distribution of Geotextiles in the United KingdomDistribution of Geotextiles in the United Kingdom

Nonwovens Wovens Knitted Extruded

55 65 10 355 3 ~ 102 10 15 20

10 2 15 53 2 5 21 ~ ~ ~1 1 ~ ~2 ~ ~ ~6 2 5 56 2 5 54 10 45 155 3 ~ 3

DamsCanals

Tunnels

RoadsRail

StructuresDrainage

Solid WasteLiquid Waste

EmbankmentsOther

Erosion

Distribution of Geotextile Use in South AsiaDistribution of Geotextile Use in South Asia

Nonwovens Wovens Knitted Extruded45% 35% 5% 15%

Nonwovens Wovens Knitted Extruded

55 35 10 355 8 ~ 102 25 15 20

10 2 15 53 2 5 21 ~ ~ ~1 1 ~ ~2 ~ ~ ~6 2 5 56 2 5 54 10 45 15

Percentage distribution of Geotextile type in the South Asia

Percentage distribution of Geotextile type per application

Solid WasteLiquid Waste

Embankments

ErosionDams

CanalsTunnels

RoadsRail

StructuresDrainage

History of Geotextiles in IndiaHistory of Geotextiles in India• Used commercially since early ’80s• However, during ’80 – ’90 the use was restricted to separation,

filtration and drainage application for both non-woven and woven type

• Indian manufacturer like Hitkari, Tata Mills etc. participated in production of non-woven type for civil engineering application

• Major boost in usage came after 1995 with major ports and highway development projects.

• Application included marine protection below rip-raps and armour layers for separation and filtration for land reclamation projects.

• Application in river Training works and erosion control also started

• National Highways saw the application in drainage, embankment protection, base course stabilization and separation below highway embankments, also protection against erosion.

• Growing usage for environmental projects such as landfills, waste storage etc.

• MSE block walls are also a major end user, specially for low – medium heights using geogrids and high strength woven Geotextile

• Now there are 10-15 non-woven as well as woven Geotextile manufacturer besides several unorganized participations

History of Geotextiles in IndiaHistory of Geotextiles in India

Few Examples of NHAI ProjectsFew Examples of NHAI Projects

Project Purpose Qty.

Visakhapatnam In Marshy/ Slushy Soils 1,08,100 sqm

Vallarpadam, Cochin

Geotextile (non woven) as separation/ filtration layer

4,30,260 sqm

Tuticorin Below sub-grade 2,55,000 sqm

Paradip (i) for high embankment over land drains

(ii) below sub-grade

1,04,250 sqm 40,640 sqm

JNPT Package II(SH-54 & Aamra

Marg)

Woven geotextile below embankment

64,600 sqm

THANK YOU FOR YOUR ATTENTIONTHANK YOU FOR YOUR ATTENTION