Special_714_Geotextile_and_Geocomposite_Drain_Material.doc

SPECIAL CONTRACT REQUIREMENTS

TO

STANDARD SPECIFICATIONS

FOR CONSTRUCTION OF ROADS

AND BRIDGES ON FEDERAL HIGHWAY

PROJECTS FP-03

DIVISION 700

MATERIALS

SECTION 714

GEOTEXTILE AND GEOCOMPOSITE DRAIN MATERIAL

Replace Section 714 in the FP-03, in its entirety, with the following:

Section 714 — GEOSYNTHETIC MATERIAL

714.01 Geotextile. Use long-chain synthetic polymers composed of at least 95 percent by mass of polyolefins or polyesters to manufacture geotextile and the threads used in joining geotextile by sewing. Form the geotextile, including selvedges, into a stable network such that the filaments or yarns retain their dimensional stability relative to each other.

Property values, with the exception of apparent opening size (AOS), in these specifications represent minimum average roll value (MARV) in the weakest principal direction (i.e., average test results of any roll in a lot sampled for conformance or quality assurance testing must meet or exceed the specified values). Values for AOS represent maximum average roll values.

Conform to the following physical requirements:

(a) Separation and stabilization geotextile and geotextile filter. Conform to Table 714-1.

Table 714-1

Separation and Stabilization Geotextile and Geotextile Filter Requirements (1)

Minimum Strength and Durability Properties

Strength

Property Test

Method ASTM

(1420)

(890)

(1110)

(710)

(1290)

(800)

(980)

(620)

(490)

(360)

(400)

(240)

(2760)

(1910)

(2220)

(1380)

Hydraulic Properties

Hydraulic

Property Test

Method ASTM

Minimum permittivity

Maximum apparent opening size

(AOS)

sieve

(mm) No. 40

(0.425) No. 40

(0.425) No. 60

(0.250) No. 40

(0.425) No. 70

(0.212)

(1) Do not use woven slit film geotextile.

(b) Paving geotextile. Conform to Table 714-2.

Table 714-2

Paving Geotextile Requirements

Type of Geotextile

Nonwoven

ADVANCE \d 3(1) Asphalt required to saturate fabric only. Value supplied by manufacturer in material certification. Value does not indicate the asphalt application rate required for construction. Product asphalt retention property must meet the MARV value provided by the manufacturer’s certification.

714.02 Geocomposite Drain. Furnish a prefabricated geocomposite geocomposite composed of a drainage core and a non-woven geotextile that permits in-flow from both sides. Geocomposites that only permit in-flow from one side may only be used directly against a concrete surface. Furnish geotextile and drainage core manufactured from long chain synthetic polymers composed at least 95 percent by mass of polypropylene, polyester, polyamide, polyvinyl chloride, polyolefin, or polystyrene. Build the core up in thickness by means of columns, cones, nubs, cusps, meshes, stiff filaments, or other configurations. Fabricate the core in sheets, panels, or rolls of adequate strength to resist installation stresses and long-term loading conditions.

Property values, with the exception of fungi resistance, in these specifications represent minimum average roll value (MARV) in the weakest principal direction (i.e., average test results of any roll in a lot sampled for conformance or quality assurance testing must meet or exceed the specified values).

Furnish a nonwoven encapsulating geotextile meeting requirements of Table 714-1. Firmly attach the encapsulating geotextile to the core at the manufacturing plant, so that folding, wrinkling, or other movement cannot occur during handling or after placement. Use a non‑water‑soluble adhesive, heat sealing, or other methods recommended by the geotextile manufacturer. Do not use adhesive on areas of the geotextile where flow is intended to occur.

If heat sealing is used, do not weaken the geotextile below the required strength values. Extend the geotextile beyond the core length on all sides sufficiently to encapsulate the core and collector pipe.

Conform to Table 714-3.

Table 714-3

Geocomposite Drain Requirements

Transmissivity

(flow rate) (1)

ASTM

D4716 gal/min/ft

(m3/sec/m) 5.0

(0.0010) 15.0

(0.0031) 20.0

(0.0041)

Compressive strength at yield

ASTM

D1621 psi

(kPa)

(690)

(340)

(340)

Applied normal compressive stress

ASTM

D4716(4)(5)(6) psi

(kPa) 14.5

(100) 1.45

(10) 1.45

(10)

D4716(2)(3)(4)

(1) If core construction separates the flow channel into two or more discrete sections, only the flow rate on one in‑flow face is considered in determining the core's acceptability.

(2) 14-inch (350 millimeter) long specimen.

(3) 100-hour seating period.

(4) Rubber membrane between platens and geocomposite.

714.03 Stabilization Geogrid. Furnish triaxial geogrid manufactured using long-chain synthetic polymers composed of at least 95 percent by mass of polyolefins, polyesters, or polyamides. Fabricate the geogrid into a stable network such that the ribs, filaments, or yarns retain their dimensional stability relative to each other, including selvages.

Property values, with the exception of maximum opening size, represent minimum average roll values (MARV) (i.e., average test results of any roll in a lot sampled for conformance or quality assurance testing must meet or exceed the minimum specified values). The value for maximum opening size represents maximum average roll value.

Conform to Table 714-4.

Table 714-4

Stabilization Geogrid Requirements

Ultraviolet stability

(retained strength)

500 hours of exposure

(1) Strength values are in the weaker principal direction.

(2) Direct measure with caliper.

(3) Geosynthetic Research Institute.

714.04 Reinforcement Geotextile and Geogrid. Furnish reinforcement geotextile manufactured using long‑chain, synthetic polymers, composed at least 95 percent by mass of polyolefins or polyesters. Form the geotextile, including selvedges, into a stable network such that the filaments or yarns retain their dimensional stability relative to each other.

Furnish reinforcement geogrid manufactured as a regular network of integrally-connected longitudinal and transverse polymer tensile elements with a geometry that permits significant mechanical interlock with the backfill. Provide geogrid composed of fibers or ribs that are at least 95 percent by mass polypropylene, polyethylene, or polyester. The geogrid structure must remain dimensionally stable under construction stresses and have a high resistance to damage during construction, to ultraviolet degradation, and to chemical and biological degradation encountered in the soil being reinforced.

Conform to Tables 714-5 and Table 714-6. Property values represent minimum average roll values (MARV) (i.e., average test results of any roll in a lot sampled for conformance or quality assurance testing must meet or exceed the minimum specified values).

The Nominal long-term strength (Tal) is based on:

Tal = Tult/RF where RF = RFID × RFCR × RFD.

RFID, RFCR, and RFD values must be substantiated by evaluation of independent test results by Highway Innovative Technology Evaluation Center (HITEC), AASHTO National Transportation Product Evaluation Program (NTPEP), or an equivalent third party report. Provide a copy of the report to the CO. Determine RFID, RFCR, and RFD according to the following:

(a) RFID: Determine the reduction factor for installation damage from the results of full scale construction damage tests conducted according to ASTM D5818. Conduct the tests with a soil having the same maximum particle size, D50, and angularity as the soil to be used for construction. Tests using coarser soils (same or larger maximum particle size and D50) may be an acceptable substitution. The CO will make the final determination as to whether the test data based on the substitute soil is acceptable. Interpolation of RFID will not be allowed, the results for the coarser soils will be used. The Contractor may elect to perform a test using project specific fill, placement, and compaction techniques and equipment to determine the RFID. Use a default value of 3.0 if no installation damage testing has been conducted. The minimum value for RFID is 1.1.

(b) RFCR. Determine the creep reduction factor according to one of the following two approaches:

(1) conventional creep testing according to ASTM D5262; or

(2) a combination of stepped isothermal method (SIM) per ASTM D6992 and conventional creep testing. Perform testing and determine creep reduction factors for a 75 year design life according to the procedures in Appendix D of Publication No. FHWA-NHI-10-025, Design and Construction of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes – Volume II. If testing has not been conducted, default values for RFCR are 2.5 for polyester polymer, and 5.0 for polypropylene or polyethylene polymer.

(c) RFD. For polypropylene or polyethylene geosynthetics conforming to the requirements of Table 714-5, a default reduction factor of 1.1 may be used for RFD. For polyester geosynthetics conforming to the requirements listed in Table 714-5, a default reduction factor of 1.15 may be used for RFD if the soil has a pH between 5 and 8; and a reduction factor of 1.3 may be used if the soil pH is between 3 and 5 or between 8 and 9.

Table 714-5

Reinforcement Geotextile and Geogrid Polymer Requirements

Polypropylene and polyethylene

D4355 Minimum 70% retained strength after 500 hours of exposure

Polypropylene and polyethylene Thermo-oxidation resistance

ENV ISO 13438: 1999,

Method A

(polypropylene) or Method B

(polyethylene) Minimum 50% retained strength after 28 days (polypropylene) or 56 days (polyethylene)

resistance

ASTM D4603

& GRI GG8 (1)

Minimum number average molecular weight (Mn) of 25,000

(CEG) of 30

unit area

ASTM

D5261 Minimum 8 oz/yd2 (270 g/m2)

Percent post consumer recycled material by mass Certification of material used Maximum 0%

Table 714-6

Reinforcement Geotextile and Geogrid Strength Requirements

Method

ASTM

Ultimate strength (3) (Tult) D4595 or

D6637 (4) lb/ft

(kN/m)

(29.2)

(43.8)

(58.4)

(73.0)

(87.6)

(116.8)

Nominal long-term strength (Tal) lb/ft

(kN/m)

(14.6)

(21.9)

(29.2)

(36.5)

(43.8)

(58.4)

(1) For reinforcement geotextile, also meet the Class 1 strength requirements in Table 714-1 and the ultraviolet stability requirements in Table 714-5.

(2) The specified strength is in the principal direction of reinforcement, i.e. perpendicular to the wall or slope face.

(3) Based on minimum average roll value (MARV).

(4) Test Method ASTM D4595 is for geotextile and ASTM D 6637 is for geogrid.

714.05 Geomembrane. Furnish geomembrane that consists of textured (roughened) surface polyvinyl chloride, high density polyethylene, or linear low density polyethylene geomembrane with a thickness of 28.5 to 31.5 mils (0.72 to 0.80 millimeters). Glue or weld seams of the geomembrane to prevent leakage. Conform to Table 714-7.

Table 714-7

Geomembrane Requirements

(1) The minimum average asperity height is 10 mils (0.25 millimeters). Of 10 readings, 8 of 10 must be greater than or equal to 7 mils (0.18 millimeters), and the lowest individual reading must be greater than or equal to 5 mils (0.12 millimeters).

(2) Geosynthetic Research Institute.