812Fence and Cattle Guards

Fence and Cattle Guards

812.0General Fence Requirements

1 Provide wire coated as follows:

2 Use one of the following:

812.1Barbed Wire

1 Provide two-wire strands with two-point, round barbs spaced at intervals no greater than 4 in [100 mm] or four -point, round barbs spaced at intervals no greater than 5 in [125 mm], double wrapped in accordance with AASHTO M 280 either:

2 For high tensile steel wire, provide two-wire strands with two-point, flat barbs spaced at intervals no greater than 5 in [125 mm] or four -point, flat barbs spaced at intervals no greater than 5 in [125 mm], double wrapped in accordance with AASHTO M 280 either:

3 Use either:

and barbs; or

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4 For braces, tie wires, and wire stays, provide 12½-gage or larger steel wire.

812.2Twisted Barbless Wire

1 Provide twisted wire consisting of two strands of 12½-gage steel wire without barbs and in accordance with AASHTO M 280.

812.3Woven Wire

1 For right -of-way and barrier fence, provide woven wire fabric in accordance with AASHTO M 279 for No. 11, grade 60, with stay wires 6 in [150 mm] apart.

812.4Industrial Fence

1 Provide industrial fence fabric of the type specified, tension wire, posts, required hardware, and fittings in accordance with AASHTO M181. Provide grade 2 posts. If not specified, aluminum or galvanized steel fabric, posts, hardware, and fittings may be used.

2 Alternatively, posts, braces, rails, and gate framing members may be steel pipe in accordance with ASTM A 569 [ASTM A 569M], with a yield strength of at least 50,000 psi [350 MPa] and with an outside diameter no less than specified for schedule 40. Ensure that the outside is coated with at least 0.9 oz/ft² [275 g/ m²] of zinc, at least 15 micrograms/ft² [25 g/m²] of zinc chromate, and acrylic at least 0.3 mil [8 µm] thick. Ensure that the inside is coated with a zinc-rich coating containing at least 80 percent zinc powder by weight [mass]. Replace pipe with visible coating damage at no additional cost to the department.

812.5Galvanized Steel Gates

1 As specified, provide galvanized steel gates of the indicated width, at least 50 in [1.3 m] high, and with hinges and fittings . Provide a frame made of 1⅜ -inch [35 mm] outside- diameter galvanized pipe with all joints welded and braced where necessary. Provide 2- inch × 4-inch [50 mm × 100 mm] V-mesh fabric with double-strand, 12½-gage [2.51 mm] horizontal wires and at least 14-gage [2.03 mm] cross or diagonal wires. Submit alternate or equivalent designs to the engineer for approval before ordering.

812.6Cattle Guard Units

812.6.1 Prefabricated

1 For prefabricated cattleguards, ensure the provision and use of cross -bar members made from carbon-steel structural tubing in accordance with ASTM A 500, grade A or B, or from cold -formed, high- tensile, low -alloy steel plate, with good weldability and in accordance with Table 812.6.1-1, Steel Plate Properties.

Fence and Cattle Guards SECTION 812

Table 812.6.1-1 Steel Plate Properties Mechanical Property Requirements Yield Point, min 45,000 psi [310 MPa] Min. Tensile Strength 60,000 psi [410 MPa]

2 Provide cattle guard supports and detachable wings fabricated from steel meeting the above requirements or from structural steel in accordance with ASTM A 709, grade 36 [ASTM A 709M, grade 250] . Concrete footings may be precast . Provide bolts in accordance with ASTM A 307 or SAE grade 2.

812.6.2 Welded Grill

1 For welded grills, provide units consisting of steel rails of the weight [mass] specified, arc-welded with low-hydrogen electrodes to structural steel beams . Salvaged rails may be used if they are clean, rust-free, of uniform section and weight [mass], and at least 95 percent of the original weight [mass] . For structural steel other than rails, ensure accordance with ASTM A 709, grade 36 [ASTM A 709M, grade 250].

812.7Nails and Spikes

1 Provide nails and spikes in accordance with the National Design Specification published by the American Wood Council . When specified, provide hot -dip galvanized nails and spikes of common diameter and length.

812.8Fence Posts

812.8.1 Wood

1 For wood fencing materials, provide and use posts, cross braces, and deadmen cut from sound, growing Douglas Fir, Lodgepole Pine, Southern Yellow Pine, or Ponderosa Pine trees. Ensure that posts have been machine- peeled, with the outer bark removed completely, and no remaining strip of inner bark is wider than 2 in [50 mm] or longer than 3 in [75 mm].

2 For line posts, ensure the wood has no seasoning check wider than ⅜ in [10 mm], dry heart, sap rot, rotten knots, or more than one 2- inch [50 mm] crook measured from end to end. Ensure the same for posts in end and brace panels, but allow no crook greater than 1 in [25 mm]. Ensure that tapering does not exceed ¼ in/ft [21 mm/m].

3 Ensure that posts are treated in accordance with American Wood Protection Association

and reports thereof are submitted, in accordance with Section 817, Structural Timber and Lumber.

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812.8.2 Steel

1 Provide steel posts, fittings, hardware, and other steel appurtenances of standard commercial grade, manufactured in accordance with current standard practice and painted with an approved, dark green paint . The top 6 in [150 mm] of posts may be painted with the supplier’s identification paint.

812.8.3 Recycled Plastic

812.8.3.1 General

1 The department will use these definitions in reference to fence posts made from recycled plastic:

material, or both, processed as necessary to make usable products.

that have been separated from solid waste for collection, recycling, and redisposition.

waste, not including materials and by -products generated from and commonly used within an original manufacturing process.

2 For recycled-plastic posts, ensure the use of at least 70 percent recycled plastic by weight [mass] and of a uniform composition throughout the post, with no more than 20 percent voids; do not use posts with a void exceeding 25 percent of the diameter or side of the post. Provide brown posts that are free of cracking, chipping, flaking, peeling, or splintering. The department will allow only chemicals, including fillers and coloring agents, designed to inhibit photo degradation, biological/biochemical decomposition, insect infestation, or burning.

812.8.3.2 Certification

1 In addition to meeting the requirements of Subsection 800.1, Manufactured Products Certifications, ensure that for each lot shipped the manufacturer certifies the following:

(consumer or industrial);

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2 Submit certifications to the engineer at least 21 calendar days before installation.

812.8.3.3 Testing

1 For each different type of recycled-plastic post (e.g. cross-section, size, and shape), the department will use an acceptance lot size of no more than one thousand posts. Ensure at least one post per lot, or a minimum of one post per project, is tested by an independent laboratory for flexural strength. Provide the engineer with a copy of the test results.

2 The department will not accept posts in a lot until the lot has been approved; do not ship lots to the project until the sample has been tested and approved. Ensure that posts are delivered in wrapped bundles of no more than 25 posts and that each bundle is marked with the lot number.

812.8.3.4 Physical Requirements

dimensions, shape, and length as specified for wood. For round posts, ensure a minimum diameter within ½ in [12 mm] of that specified.

straightness criteria specified in Subsection 812.8.1, Wood.

the specifications for flexural strength in the Western Wood Products Association

timber, with maximum or extreme fiber stress of at least 1000 psi [6895 kPa]. Test posts in accordance with ASTM D 6109.

finish relatively free of surface imperfections.

812.8.3.5 Fasteners

1 For attaching wire fence to recycled- plastic posts, provide and use fasteners that connect at predrilled pilot holes; do not use staples or nails.