of the nominal steel areas shown in table 1 of ASTM A 416 [ASTM A 416M].
Ensure that high-tensile-strength alloy bars have been thermally stress-relieved to produce a suitable, uniform metallurgical structure, and individually proof- tested during manufacturing to at least 90 percent of the manufacturer’s minimum guaranteed ultimate strength. Provide bars in accordance with Table 811.5-1, Prestressing Steel Mechanical Properties. Table 811.5-1 Prestressing Steel Mechanical Properties Mechanical Properties
Regular Grade
Special Grade
Ultimate tensile strength, min., psi [MPa]
145,000 [1000]
160,000 [1100]
Yield strength (measured by the 0.7% extension-under-load method), min., psi [MPa]
130,000 [900]
140,000 [965]
Elongation, % min. (in 20 bar diameters after rupture)
4.0
4.0
Reduction of area, %, min.
Modulus of elasticity (at 70% of manufacturer’s min. guaranteed ultimate strength), min., psi [MPa]
25 × 106 [1.72 × 105]
25 × 106 [1.72 × 105]
4 Ensure that diameter tolerances are in accordance with ASTM A 29 [ASTM A 29M]. Use
only one grade of bars for any individual member.
811.6Gabions and Revet Mattresses
1 For gabions and revet mattresses, provide and use a woven wire fabric in accordance
with ASTM A 975, style 1. 2 Provide
as specified in the contract, galvanized, smooth steel lacing and tie wire; galvanized hog rings may be used to fasten ends, sides and top panels. 3 For steel stakes, provide 5-foot [1.5 m] crane rails, nominal 3-inch [75 mm] standard
pipe, or angles 4 in × 4 in × ⅜ in [100 mm × 100 mm × 10 mm]. Rail, pipe, or angles free from rust or damage that could affect the stake’s strength may be reused.
713
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
714
Fence and Cattle Guards