712.01 Chain Link Fence
712.01.1 General
Meet AASHTO M 181 requirements, as modified herein. Use one of the following fence fabrics, as specified in the contract: • Type 1 Class C zinc-coated steel • Type 2 aluminum-coated steel • Type 3 aluminum alloy Zinc-5% aluminum-mischmetal alloy in accordance with ASTM B750 may be substituted for zinc coating (hot-dipped) at a Class 2, or 1.0 oz/ft2 (305 g/m2), coating thickness as specified by ASTM F1345. Use zinc-coated steel for all Type 1 and Type 2 fabric fence parts: including posts, rails, gate frames, expansion sleeves, wire ties, fabric ties, hog rings, tension wire, miscellaneous fittings, and hardware. Use aluminum alloy for these same Type 3 fabric fence parts. Use either zinc- coated steel or aluminum alloy for these Type 4 fabric fence parts.
712.01.2 Fence Fabric
Furnish fence fabric having 2-inch (50 mm) openings and in accordance with AASHTO M 181. Use 11-gauge wire for fabric 48 inches (1,220 mm) high and under. Use 9-gauge wire for fabric 60 inches (1,525 mm) high and over. The fabric height is specified in the contract.
712.01.3 Posts, Rails, and Braces
Meet ASTM F1043 and the contract length requirements. Furnish all posts with a watertight cap that fits securely over the outside post top and supports the top rail.
712.01.4 Truss Rods
Furnish ⅜-inch (9.5 mm) truss rods as follows: • Steel - galvanized with dropforged turnbuckles or other approved type of adjustment. • Aluminum - with cast aluminum turnbuckles or other approved type of adjustment.
712.01.5 Fabric Bands and Stretcher Bars
Furnish bands as follows: • Steel - a minimum ⅛-inch (3 mm) thick x 1-inch (25 mm) wide. • Aluminum - a minimum ⅛-inch (3 mm) thick x ⅞-inch (22 mm) wide. Furnish aluminum or steel stretcher bars as follows: • A minimum ¼-inch (3 mm) thick x ¾-inch (19 mm) wide. • At least 2 inches (50 mm) shorter than the fabric width used.
712.01.6 Tie Wire
Furnish 9-gauge galvanized steel tie wire in accordance with AASHTO M 279. Furnish 11- gauge; Class 1 galvanized steel hog ring fasteners in accordance with AASHTO M 279. Furnish 9-gauge aluminum tie wire in accordance with ASTM B211 Alloy 1100, Temper H14. Furnish minimum 11-gauge aluminum hog ring fasteners in accordance with ASTM B211, Alloy 6061.
712.01.7 Tension Wire
Furnish 7-gauge galvanized coiled spring steel tension wire. Meet AASHTO M 279, Class 1 galvanizing requirements. 712 – FENCING MATERIALS 2020 EDITION V5.1 712-2 Furnish 6-gauge aluminum tension wire in accordance with ASTM B211, Alloy 6061, Temper T 94.
712.01.8 Gates
Furnish gates complete with all necessary hinges, latch, and drop-bar locking device for the type of gate and gateposts specified. Weld in accordance with Section 624.
A.Steel Gates. Construct gate frames from steel sections in accordance with ASTM F900. The gate frame corners may be welded or fastened and reinforced with galvanized malleable-iron fittings designed for this use. Use chain link fabric for gate frames in accordance with Subsection 712.01.2 and match the fabric used in the fence.
B.Aluminum Gates. Construct gate frames from aluminum sections in accordance with ASTM F900. Assemble the gates frames by welding. Use aluminum alloy cast hinges in accordance with ASTM B108 or B26 or made of malleable iron or steel and hot-dip galvanized or mechanically galvanized in accordance with ASTM B695 (Class 50). Make all latches, stops, and keepers of the aluminum alloy specified for hinges or use galvanized malleable iron or pressed steel. Use chain link fabric for the gate frame in accordance with Subsection 712.01.2 and matching the fabric used in the fence.
712.02 Wire Fence
712.02.1 Woven Wire
Furnish woven wire in accordance with AASHTO M 279 and either of Table 712-1 designations. TABLE 712-1 WOVEN WIRE REQUIREMENTS Specification Grade Design Number Metallic Coating AASHTO M 279 No. 12½ Grade 60 832-6-12 ½* Type Z, Class 1 or Type ZA, Class 20 AASHTO M 279 No. 14 Grade 125 832-6-14* Type Z, Class 3 or Type ZA, Class 40 *For use with Type C fence. Provide a 6-inch (150 mm) stay spacing. Match the fence height and mesh dimensions of the fence being replaced if not specified.
712.02.2 Barbed Wire
Use 2-point 12½ or 13½-gauge barbed wire in accordance with AASHTO M 280. Space barbs at a 4-inch nominal (100 mm) or a 5-inch nominal (130 mm) spacing. Provide the Project Manager certification that the wire is in accordance with AASHTO M 280.
712.02.3 Brace Wire
Use 9 or 12½-gauge soft, smooth wire.
712.02.4 Staples and Nails
Use minimum 9-gauge U-shaped, 1¾-inch (45 mm) long staples unless otherwise specified in the contract. 2020 EDITION V5.1 FENCING MATERIALS – 712 712-3
712.02.5 Tie Wires
Use minimum 12½-gauge galvanized tie wire. Commercial galvanized fasteners supplied with the wire may be used if approved by the Project Manager.
712.02.6 Metal Fence Stays
Use commercially made and fabricated metal fence stays from 9½-gauge wire twisted to form a two-wire unit.
712.02.7 Metal Posts and Assemblies
Provide metal fence posts and assemblies in accordance with AASHTO M 281, modified as follows: • Section 7 and Tables 3 and 4 of AASHTO M 281 apply to finished posts and assemblies after fabrication, punching, drilling, and finish coating. Galvanize or paint posts, braces, and anchor plates. Meet AASHTO M 111 galvanizing requirements. Furnish nuts, bolts, fittings, and other hardware in accordance with ASTM A153 or B695 (Class 50) galvanizing. Paint following the paint manufacturer’s recommendations. Furnish fence posts and braces of the lengths shown in Table 712-2 . TABLE 712-2 POST LENGTHS Post Type Braces, Brace Rails And Panel Posts Line Posts Metal -- 6 feet - 6 inch (2.0 m) Wood 8 feet (2.4 m) 7 feet (2.1 m) Use Tee, Channel, U, or Y bar section line posts with corrugations, knobs, notches, holes, or studs placed to engage the fence line wires. Attach a steel anchor plate to each line post so that the anchor top is 2 to 3 inches (50 to 75 mm) below ground line when the post is set to the specified depth.
712.02.8 Wood Fence Posts and Brace Rails
A.General. Make fence posts and brace rails from well-seasoned, sound, and straight- grained western larch, lodgepole pine, ponderosa pine, southern yellow pine, or Douglas fir. Remove all bark from the posts. Taper round posts, to be driven, from 6 to 12 inches (150 to 305 mm) up from the bottom to a 1 ± ½-inch (25 ± 12 mm) point. Bevel the edges of post tops to produce a flat surface with a diameter 1 ± ½-inch (25 ± 12 mm) less than post diameter. These taper lengths are included in the specified post lengths. Perform all machining before treatment. Furnish posts and rails 10 feet (3 m) in length or less free of crooks and sweeps greater than ¾-inch (19 mm) from the post centerline. The maximum offset from centerline for posts and rails longer than 10 feet (3 m) is ¾ plus 1⁄16-inch (19 plus 2 mm) per additional foot (305 mm) of length. The centerline is defined as a straight line from the center of the tip to the center of the butt. Treat round posts and rails meeting AWPA Standards for Commodity Specification B and Use Category 4A. Supply round posts and rails meeting the AWPA minimum penetration requirements specified for natural posts, with a penetration of at least ⅜-inch (9 mm). Posts and rails must have sufficient sapwood to provide the ⅜-inch (9 mm) minimum penetration. Treat the S4S post in accordance with Subsection 706.04 . 712 – FENCING MATERIALS 2020 EDITION V5.1 712-4 Treat injuries, cuts, and holes in timber posts after treatment in accordance with Subsection 706.04.
B.Line Posts. Furnish line posts and brace rails from a minimum 4-inch (100 mm) diameter round, or a minimum 4 x 4-inch (100 x 100 mm) square sawn. Furnish corner, end, gate, and pull posts from a minimum 5-inch (130 mm) diameter round post or a 5 x 5-inch (130 x 130 mm) square sawn post.
712.02.9 Metal Gates
Furnish each gate complete with hinges, latch, and all other hardware used with the type of gate and gate post specified.
712.02.10 Gates for Interstate Fence
Use plain-top single-drive metal gates of tubular steel frame with wire fabric filler. Fit the gate to the opening between the gate posts of the approximate widths shown in the Detailed Drawings. Provide a centered steel upright brace for gates for openings of less than 14 feet (4.3 m), two upright steel braces at third points for gates for openings of 14 feet (4.3 m) or greater. Fill the metal gates with galvanized wire fabric securely fastened to the top, bottom, ends of the gate frame. Use fabric in accordance with Subsection 712.02.1, Class 1 or better. The approximate weight of the gate frames (less fabric) must meet Table 712-3 requirements. TABLE 712-3 APPROXIMATE GATE FRAME WEIGHTS Width of Opening Approximate Wt1 8 feet (2.4 m) 48 pounds (22 kg) 10 feet (3.0 m) 55 pounds (25 kg) 12 feet (3.7 m) 62 pounds (28 kg) 14 feet (4.3 m) 72 pounds (33 kg) 16 feet (4.9 m) 80 pounds (36 kg) Notes:
1.Heavier gates will be permitted if they meet all other requirements.
712.02.11 Gates for Farm Fence
Furnish farm fence gates in accordance with the Detailed Drawings and contract.
712.02.12 Deadman or Anchor
Furnish deadman and anchor(s) in accordance with the Detailed Drawing.
712.02.13 Miscellaneous
Bolts, nuts, fittings, hinges, and all other metal parts for constructing fences and gates must be galvanized in accordance with ASTM specifications.
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Source: Standard Specifications for Road and Bridge Construction, 2020 (v5.1) Edition. Pages 581–584 of 611. View official source ↗