Specifications_Revised.pdf

Cannon AFB East Aderholt Loop Repair CAFBADERHOLTLOOP

SECTION 31 05 21***ADM001***

GEOGRID SOIL REINFORCEMENT

08/08

03/31/2015

PART 1 GENERAL

1.1 REFERENCES

The publications listed below form a part of this specification to the extent referenced. The publications are referred to within the text by the basic designation only.

ASTM INTERNATIONAL (ASTM)

ASTM D4355 (2007) Deterioration of Geotextiles from Exposure to Light, Moisture and Heat in a Xenon-Arc Type Apparatus

ASTM D4595 (2011) Tensile Properties of Geotextiles by the Wide-Width Strip Method

ASTM D4873 (2002; R 2009) Identification, Storage, and Handling of Geosynthetic Rolls and Samples

ASTM D5262 (2007) Evaluating the Unconfined Tension Creep Behavior of Geosynthetics

ASTM D6637 (2011) Standard Test Method for Determining Tensile Properties of Geogrids by the Single or Multi-Rib Tensile Method

GEOSYNTHETIC INSTITUTE (GSI)

GSI GRI GG4a (2012) Determination of the Long-Term Design Strength of Stiff Geogrids

GSI GRI GG4b (2012) Determination of the Long-Term Design Strength of Flexible Geogrids

1.2 SUBMITTALS

Government approval is required for submittals with a "G" designation;

submittals not having a "G" designation are for Contractor Quality Control approval.Submit the following in accordance with Section 01 33 00 SUBMITTAL

PROCEDURES:

SD-02 Shop Drawings

Installation; G

SD-03 Product Data

Allowable Strength Manufacturer

***ADDENDUM 001***

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SD-04 Samples

Geogrid Reinforcement

SD-06 Test Reports

Geogrid Reinforcement Coefficient of Interaction Interface Friction Testing Splices Conformance Testing

SD-07 Certificates

Certificates of Compliance

1.3 QUALITY ASSURANCE

Submit a summary of the manufacturer's qualifications and 2 copies of the manufacturer's quality control (QC) manual a minimum of 7 days prior to delivery of geogrid to the site. The reinforcement manufacturer shall provide a qualified and experienced representative to be available on an as-needed basis during construction. The representative shall visit the site for consultation as requested by the Contracting Officer.

1.4 DELIVERY, STORAGE, AND HANDLING

Check products upon delivery to ensure that the proper material has been received and is dry and undamaged. Protect the materials from damage and exposure following the guidelines presented in ASTM D4873.

1.4.1 Labeling

Label each roll with the manufacturer's name, product identification, roll dimensions, lot number, and date manufactured.

1.4.2 Handling

Handle and unload geogrid rolls by hand, or with load carrying straps, a fork lift with a stinger bar, or an axial bar assembly. Geosynthetic rolls shall not be dragged, lifted by one end, lifted by cables or chains, or dropped to the ground.

1.4.3 Storage

Protect geogrid from deleterious materials, chemicals, sparks and flames, temperatures in excess of 160 degrees F, and any other environmental condition that may degrade the physical properties. If stored outdoors, the rolls shall be elevated from the ground surface. Protect geogrids, except for extruded grids, with an opaque waterproof cover.

PART 2 PRODUCTS

2.1 GEOGRID REINFORCEMENT

Submit one properly identified 24 by 24 inches minimum size geogrid sample with the fasteners proposed for use. Provide a geogrid that is a geosynthetic manufactured for reinforcement applications and a regular

SECTION 31 05 21 Page 2 network of integrally connected polymer tensile elements with aperture geometry sufficient to permit significant mechanical interlock with the surrounding soil, aggregate, or other fill materials.

a. Submit manufacturer's certified raw and roll material test reports including ultimate strength performed in accordance with ASTM D6637 or ASTM D4595 (modified). Test results not meeting the requirements in Table 1 or in the approved Manufacturer's Quality Control Manual will result in rejection of applicable rolls. Provide certified test reports a minimum of 7 days prior to delivery of geogrid to the site.

b. The geogrid structure shall be dimensionally stable and able to retain its geometry under manufacture, transport and installation. The geogrid shall be manufactured with 100 percent virgin resin consisting of polyethylene, polypropylene, polyester, or other approved material and with a maximum of 5 percent in-plant regrind material. Polyester resin shall have a minimum molecular weight of 25,000 and a carboxyl end group number less than 30. Polyethylene and polypropylene shall be stabilized with long term antioxidants.

c. Submit Certificates of Compliance for the materials provided and results of conformance testing. Submit an affidavit certifying raw and roll material test results submitted are accurate and that the reinforcement meets the requirements of the project specifications.

The affidavit shall be signed by an official authorized to certify on behalf of the manufacturer. If the affidavit is dated after award of the contract and/or is not specific to the project, the supplier shall attach a statement certifying that the affidavit addressed to the wholesale company is representative of the material supplied. The documents shall include a statement confirming that all purchased resin used to produce reinforcement is virgin resin. Provide affidavit a minimum of 7 days prior to delivery of geogrid to the site.

2.1.1 Geogrid Reinforcement Properties

The reinforcement shown on the contract drawings shall meet the property requirements listed in Table 1. Reinforcement strength requirements represent minimum average roll values in the machine direction.

TABLE 1

PROPERTY REQUIREMENT TEST DESIGNATION

Radial stiffness at low strain (0.5 percent strain)

1715 lb/inch ASTM D6637

UV Resistance 70 percent after 500 hours

ASTM D4355

Junction efficiency 0.93 ASTM D6637

2.1.1.1 Allowable Strength

Submit Geogrid allowable strength calculated in accordance with GSI GRI GG4a or GSI GRI GG4b. The calculations shall itemize each reduction factor.

SECTION 31 05 21 Page 3

Provide calculations a minimum of 7 days prior to delivery of geogrid to the site. Allowable strength is based on reduction factors for installation damage, durability, and creep that are applicable to site specific conditions. Determine reduction factors in accordance with the test procedures documented in GSI GRI GG4a or GSI GRI GG4b. The minimum reduction factor for durability shall be 1.1 for polyethylene and polypropylene geogrids and 1.15 for coated polyester geogrids. The minimum reduction factor for installation damage shall be 1.1 for all polymers.

The reduction factor for creep shall be based on testing performed in accordance with ASTM D5262 at the strain specified in Table 1.

PART 3 EXECUTION

3.1 INSTALLATION

3.1.1 Subgrade Preparation

Immediately prior to placement of the geogrid, the surface on which the geogrid will be placed shall be free of rock and other material that could damage the geogrid or the underlying geosynthetics.

3.1.2 Placement

Install the geogrid in accordance with the Manufacturer's recommendations.

Unroll the geogrid in the direction of reinforcement. After a layer of geogrid has been placed, use suitable means, that do not damage the underlying geosynthetics, to hold the geogrid flat and in place until cover soil can be placed. Geogrid damaged during placement and covering shall be removed and replaced at no additional cost to the Government.

3.1.3 Overlap

Overlap adjacent rows per manufacturer's recommendations.

3.2 COVER SOIL PLACEMENT

Cover geogrid with soil within 5 calendar days of acceptance. Keep the geogrid smooth and taut during placement of cover materials. Cover soil shall not be dropped onto the geogrid from a height greater than 3 feet.

The soil shall be pushed out over the geogrid in an upward tumbling motion. Place soil from the bottom of the slope upward. The initial loose soil lift thickness shall be 12 inches. Use equipment with ground pressures less than 7 psi to place the first lift over the geogrid. A minimum of 18 inches of soil shall be maintained between construction equipment with ground pressures greater than 7 psi and the geogrid.

Equipment placing cover soil shall not stop abruptly, make sharp turns, spin their wheels, or travel at speeds exceeding 5 mph. Additional cover soil material and placement requirements are described in Section 31 00 00

EARTHWORK.

3.3 OVERSIGHT

Keep a QA Representative present at all times during geogrid installation.

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