1. Specifications for Geotextiles in India by R. P. Indoria Secretary General, Indian Roads Congress 19 November 2010

2. ABOUT IRC  Indian Roads Congress is a Society of Highways Engineers established in 1934  Frames Codes of Practice, Standards, Guidelines, Manuals etc. on various subjects for Roads and Bridges  Identification of research topics and Institutions  Collection of data on research done and utilization there of (Cont…)

3. ABOUT IRC  Dissemination of Research findings for revision of IRC Codes and Special Publications  Holding Workshops and Seminars on Crucial Topics for dissemination of knowldge  Promoting Usages of New Materials and Technologies

4. IMPORTANCE AND USAGES OF GEOTEXTILE IN ROAD SECTOR  Use as Separator to Improve Pavement Performance  Use as reinforcement and drainage layer  Use for Ground Improvement  Use for drainage of ground (PVD/piped drains)  Jute Geogrid for Erosion Control of Denuded Slopes  Jute Geotextile for Drainage and Filtration Application  Jute is low cost, renewable, biodegradable and eco-friendly natural product (Cont…)

5. IMPORTANCE AND USAGES OF GEOTEXTILE IN ROAD SECTOR  Construction of road embankments in water logged area  Soil Nailing  River Bank Protection  Embankment slope protection

6. TYPES OF GEOTEXTILES Geotextile: Non Biodegradable Synthetics Woven / Non Woven Fiber and perform discrete function i.e. separation, reinforcement, filtration, drainage and moisture barrier (when impregnated). Geogrids :Open, grid like configuration, i.e., they have large apertures and used for the purpose of separation, but invariably they are being used in some form of reinforcement. ( Cont…)

7. TYPES OF GEOTEXTILES Geonets: another specialized segment of Geosynthetics and Geonets are used for the purpose of drainage. It is to be noted that geonets are always used with a geotextile. Geonets used in protective works for highway structures Geocomposite: A geocomposite consists of a combination of geotextile and/or geogrid and/or geomembrane or any of these three materials with another material in laminated or composite form and used for accelerating the consolidation of soft soils. (Cont…)

8. TYPES OF GEOTEXTILES Geomembranes : Geomembranes are also synthetic materials but they are impervious and made of thin sheets of rubber or plastic materials used primarily for lining and cover of liquid-or solid-storage facilities Geocell : A three dimensional structure with interconnected cells which can be filled with soil/granular material forming a mattress for increased bearing capacity and manoeuvrability on loose or compressible subsoil of base or sub-base in pavements and slope protection (Cont…)

9. TYPES OF GEOTEXTILES Natural Geotextiles: Natural fibres are extracted from plants and are then converted into yarns by spinning. These fabrics are sometimes treated with rot resistance materials or reinforced with synthetic fibres to enhance their durability under different soil conditions without affecting its strength and other properties. Natural fibres such as jute, coconut and coir fabrics are used to improve soil erosion control and drainage applications.

10. USE OF GEOTEXTILE FOR IMPROVING PERFORMANCE OF ROADS Geosynthetics for Highway Pavements Geosynthetics Over Existing Bituminous Surface Provision of Geotextiles Against Subgrade and Embankment Erosion Geotextiles In Sub-surface and Composite Drains Geogrid Applications For Reinforced Soil Slope Protection

11. USE OF GEOTEXTILE FOR IMPROVING PERFORMANCE OF ROADS Road pavement as a drainage layer, Bioengineering measure for shoulders and earthen slopes, Improving the pavement performance and Reducing the pavement crust (?) Construction of road embankments in water logged area Soil Nailing, Soil Stabilization

12. IRC DOCUMENTS ON GEOTEXTILES IRC has one document titled “State of the Art: Application of Geotextiles in Highway Engineering” published by IRC in 1994 It is a compilation of available literature (at the time of preparation of the report) Since then a lot of developments have taken place in manufacturing and preparation of geotextiles, their usage and applications etc.

13. IRC DOCUMENTS ON GEOTEXTILES IRC has another document titled SP:59 – 2002 `Guidelines for use of Geotextiles in road pavements and associated works` Being a Special Publication, this document does not have the status of a ‘Code of Practice” per se but nevertheless covers the following:  Scope  Raw Material and types of Geotextiles  Functions of Geotextiles

14. IRC DOCUMENTS ON GEOTEXTILES  Handling and storage of geotextiles  Geotextiles properties and test methods  Geotextiles property requirements for various applications  Construction guidelines for use of geotextiles in various applications  References have been made to ASTM standards for test methods

15. GEOTEXTILES SPECIFICATIONS More comprehensive specifications are included in the Ministry of Road Transport and Highways book of Specifications, popularly known as the “Orange Book” The current edition of this book is also very old (2001) and a revision of the book has been almost finalised and is likely to be published soon

16. GEOTEXTILES SPECIFICATIONS The proposed specifications(section 700) cover the following: 1GEOSYNTHETICS IN ROAD AND BRIDGE WORKS  Scope  Testing, handling, certification, and acceptance

17. Minimum Geotextile strength property requirements Installation condition TypeStrength property requirement (MARV)* Grab Strength in N as per ASTM D 4632 Tear Strength in N as per ASTM D 4533 Puncture Strength in N as per ASTM D 4833 Burst Strength in N as per ASTM D 3786 Elongation at Failure <50 % >50 % <50 % >50 % <50 % >50 % <50 % >50 % Harsh installation Type 1140090050035050035035001700 Moderate Installation condition Type II110070040025040025027001300 Less Severe Installation condition Type III8005003001803001802100950

18. Geotextile Requirements for Ultra Violet Light Degradation S.NoProperties of FabricTest Methods UnitsRequirements (Retained Strength) 1Grab StrengthASTMD 4632NNot less than 70% after 500 hrs of exposure 2Tear StrengthASTMD 4533N 3Puncture StrengthASTMD 4833N 4Burst StrengthASTMD 3786N

19. Properties for Prefabricated Vertical Drains Unit Minimum ValueTest Method Physical Requirements Weightgm/sq. m90- Widthmm90- Thicknessmm5- Strength Requirements Tensile StrengthkN≥ 1 at 10% elongationASTM D4632 Puncture StrengthN150ASTM D 4833 Tear StrengthN200ASTM D 4533 Discharge Capacity Index text using deformable foam layers m 3 /sec60x10 -6 (300kPa) 40x10 -6 (500kPa) ASTM D- 4716 Straight – embedded in bentonite m 3 /sec90x10 -6 (300kPaASTM D- 4716 Buckled – embedded in bentonite m 3 /sec80x10 -6 (300kPaASTM D- 4716

20. Typical Specifications for Geocells PropertyMin. Required ValueTest method Density0.935gm/cm 3 ASTM D1505 Environmental Stress crack resistance (ESCR) 5000 Hrs.ASTM D1693 Carbon Black Content1.5 to 2% by Weight Strip / Cell Wall thickness1.27mm, -5% +10%ASTM D5199 Seam Peel-Strength TestMin. 355 N per 25mm of cell depth.ASTM E41 Creep Rupture StrengthCreep Rupture Load at 10,000 hours shall be 95 kg minimum obtained from the 95% prediction interval at 10,000 hours considering a logarithmic time/creep rupture model. ASTM D2990

21. Typical Specifications of Natural Geotextile Type of Fibre WeightWidthThicknessOpen Area Tensile Strength (KN/m) Water Holding Capacity Porometry (O 95 ) (gsm)(cm)(mm)(%)MDCD(%)micron Open Mesh 5001204.050107.5-- Woven Geotextile 1)Ordinary700752.0-20 -300 2) Rot Resistance 700752.0-20 -300 3)Bitumen treated 1200752.0-20 -150 Non- woven Fibre 5001504.0-52.5300-

22. 2GEOTEXTILES IN SUB SURFACE DRAINS  Scope  Materials  Construction requirements  Measurement for payment  Rate

23. Geotextile Requirements for Subsurface Drainage Per cent in-situ passing 0.075 mm sieve Geotextile drainage property requirement Recommended geotextile * Permittivity, per sec ASTM D 4491 (Minimum ARV) Apparent opening size, mm ASTM D 4751 (Maximum ARV < 150.50.43Type II from Table 700-1 15 to 500.20.25 > 500.10.22

24. Recommended Permittivity for Different Soils Soil typeTypical Permeability, Ks (cm/sec)Range of Soil Minimum Recommended Geotextile Filter Permittivity, Y(per second) Sandy Gravel1 X 10-1 to 1 X 10-20.5 to 0.1 Clean Sand1X10-2 to 1 X 10-30.1 to 0.01 Silty Sand1X10-3 to 1 X 10-40.01 Silt1X10-4 to 1X10-50.01 Clay1X10-50.01

25. 3USE OF GEOSYNTHETICS IN COMPOSITE DRAINS  Scope  Material  Installation  Measurement for payment  Rate Apparent Opening Size for Geo-composite Drains Test MethodUnits Requirements Percent in-situ soil passing 0.075 mm ASTM D 4751mm<1515 to 50>50 0.430.250.22**

26. 4GEOTEXTILES FOR EROSION CONTROL  Scope  Materials  Construction requirements  Slope protection placement  Seams  Repair  Measurement for payment  Rates

27. Erosion Control Geotextile Requirements Percent in-situ passing 0.075 mm sieve Geotextile drainage property requirement Recommended geotextile Permittivity, per sec ASTM D 4491 (Min. ARV) Apparent opening size, mm ASTM D 4751 (Max. ARV) <150.70.43Type I from table 701 15 to 500.20.25 >500.10.22

28. 5GEOGRID APPLICATIONS FOR REINFORCED SOIL SLOPE PROTECTION  Description  Material  Installation  Measurement and basis for payment  Rates

29. 6GEOSYNTHETICS FOR HIGHWAY PAVEMENTS  Scope  Materials  Certification  Installation  Measurement for payment  Rate

30. Separation/Filtration Property Requirement for subgrade Soil with LL < 35 (such as ML, CL, CL-ML etc) ** ** The soil classification shall be as per BIS-1498 – 1970 (Re-affirmed 1987) Sl. No.Geotextile PropertyRequirement Recommended Geotextile 1. Permittivity* as per ASTM D 4491 0.02 sec -1 (per sec) (Minimum average roll value) Type II from Table: 701 2. Apparent Opening Size as per ASTM D 4751 0.06 mm (Maximum average roll value)

31. Separation/Filtration Property Requirement for subgrade Soil with LL > 35 (such as CL, CH, MH etc)** ** The soil classification shall be as per BIS-1498 – 1970 (Re-affirmed 1987) Sl. No. Geotextile Property Requirement Recommended Geotextile 1. Permittivity* as per ASTM D 4491 0.05 sec -1 (per sec) (Minimum average roll value) Type I from Table: 701 2. Apparent Opening Size as per ASTM D 4751 0.43 mm (Maximum average roll value)

32. Requirements for Geogrid for Sub-Base/base of Flexible Pavements Note1)All numerical values in the Table represent MARV in the specified direction. 2) All geogrids shall be placed along machine direction parallel to the centre line of roadway alignment. 3) Junction strength is required to maintain dimensional stability of the geogrid during deployment. It is not applicable to geogrid/geotextile composite products. Property Test Method Required value, kN/m Machine Direction Cross Direction Tensile strength@1% strainASTM D6637 4.36.6 Tensile strength@2% strainASTM D6637 7.310.9 Tensile strength@5% strainASTM D6637 13.419.7 Tensile modulus @5% strain ASTM D4355437656 Junction Efficiency, % of rib ultimate tensile strength 90 Ultraviolet stability (after 500 hrs) ASTM D435570 %

33. 7GEOSYNTHETICS OVER EXISTING BITUMENOUS SURFACE  Scope  Paving Fabrics  Material Requirement  Specifications for bitumen coated fiber glass fabric  Placement  Measurement  Rate

34. Physical Requirements for Paving Fabrics PropertyUnitsStandard Requirements Test Method Tensile StrengthKN/m9KN/mASTM D 4632 Elongation% ≥ 50ASTM D 4632 Mass per unit area Gm/m 2 140ASTM D 3776 Asphalt Retention Kg/10 sq.m10Texas DOT 3099 Melting Point°C150ASTM D 276 Surface Texture-Heat bonded on One side only Visual Inspection

35. Properties for Glass Grid Fiber PropertyTest MethodGrid Tensile strength MD (kN/m) ASTM 6637/ ISO 13439 ≥ 50 CMD (kN/m) ≥ 50 Elongation at break (%) >5 Minimum Mesh size (mm) 12.5 x 12.5 Melting point 0 C->218

36. Framework for promoting usages of Geotextile  Majority of the National Highway Development Programme to be implemented on PPP mode on BOT basis  The use of geotextile for road structure i.e. part of new or existing pavement does not bring the desired reduction in crust thickness since the pavement has to be designed as per IRC:37  There is a strong need to establish relationship between use of a type of geosynthetic and corresponding reduction in crust thickness

37. Framework for promoting usages of Geotextile This can only be achieved by concerted research (may be industry sponsored) with the involvement of research institutes and academia This could lead to formulation of definitive specifications and design methods using geotextiles/ geosynthetics For the interim, the Government has created an enabling environment for the Concessionaire to use any material / technology / equipment as long as it meets any of the established international standards

38. Framework for promoting usages of Geotextile The Manuals for four and six laning of highways, which form part of the Concession agreement, have been published by IRC containing this provision Industry need to come out with ways and means to demonstrate to the prospective users (Concessionaires) the cost effectiveness (short term and long term) of the use of geotextiles Industry also to come out with other innovative usage of geosynthetics besides the existing ones

39. Framework for promoting usages of Geotextile On our part in IRC we have started a process of accreditation of new material / technologies / equipment etc. for use in the design and construction of highways The proposals are examined by an Accreditation Committee constituted within IRC and comprising of experts from public as well as private sector Upon satisfaction, the Committee issues an Accreditation Certificate which acts as a confidence measure with the prospective buyers

40. Framework for promoting usages of Geotextile We also insist on field trial / usage reports from clients In case of satisfactory performance reports, the new material, technology or equipment will then be suitably incorporated in Codes of Practices / Specifications

41. Conclusion Need to establish relationship with cost (crust) reduction with usage of geosynthetics Concerted research to have road crust design methods and formulate specifications Concessionaires to be apprised of benefits of geosynthetics

42. Thank You for your kind attention