-3.02 STEEL STANDARDS, POLES, PEDESTALS, AND POSTS

56-3.02A(4)(c) Department Acceptance

56-3.02B Materials

56-3.02B(1) General

1. At least 0.120-inch-thick galvanized steel

2. 4-inch standard weight galvanized steel pipe complying with ASTM A53/A53M

3. 4-inch Type 1 conduit with the top designed for post-top slip fitter

Handhole reinforcement rings must be continuous around the handholes.

Galvanize standards, poles, pedestals, posts, fasteners, and other ferrous materials under section 75-1.02B.

56-3.02B(2) Bolted Connections

HS anchor bolts, nuts, and washers must comply with section 55-1.02D(1).

Bolts, nuts, and washers for general applications must comply with section 55-1.02D(1).

HS bolts shown to be snug tight must comply with section 55-1.02D(1) for general applications.

HS bolts, nuts, and flat washers used to connect slip base plates must comply with the requirements for HS fastener assemblies for use in structural steel joints in section 55-1.02D(1) except rotational capacity testing and tension testing are not required.

Zinc-coated nuts used on fastener assemblies having a specified preload obtained by specifying a prescribed tension, torque value, or degree of turn must be provided with a colored lubricant that is clean and dry to the touch. The lubricant color must contrast the zinc coating color on the nut such that the presence of the lubricant is visually obvious. The lubricant must be insoluble in water or the fastener components must be shipped to the job site in a sealed container.

Plate washers must be manufactured by saw cutting and drilling steel plate. Steel plate must comply with AISI 1018. Before galvanizing, remove burrs and sharp edges and chamfer both sides of holes to allow the bolt head to make full contact with the washer without tension.

HS cap screws for attaching arms to standards must comply with ASTM A325 or A449, and the mechanical requirements in ASTM A325 after galvanizing. Coat threads of cap screws with a colored lubricant that is clean and dry to the touch. The lubricant color must contrast the zinc coating color on the cap screw such that the presence of the lubricant is visually obvious. The lubricant must be insoluble in water or the fastener components must be shipped to the job site in a sealed container.

Before manufacturing, details must be adjusted to ensure that cap screw heads can be turned using conventional installation tools. During manufacturing, properly locate the position of the luminaire on the arm plate to avoid interference with the cap screw heads.

56-3.02B(3) Standards and Poles

56-3.02B(3)(a) General

Tapered tubes must be manufactured from sheet steel of a weldable grade having a minimum yield strength of 55,000 psi after manufacturing.

56-3.02B(3)(b) Fabrication

When a single-ply 5/16-inch-thick pole is specified, a 2-ply pole with equivalent section modulus may be substituted.

Standards may be manufactured of full-length sheets or shorter sections. Each section must be manufactured from 1 or 2 pieces of sheet steel. If 2 pieces are used, the longitudinal welded seams must be directly opposite from one another. If the sections are butt-welded together, the longitudinal welded seams of adjacent sections must be placed to form continuous straight seams from the base to the top of the standard.

Standards with an outside diameter of 12 inches or less must be round. Standards with an outside diameter greater than 12 inches may be round or multi-sided. Multi-sided standards must:

1. Be convex

2. Have a minimum of 12 sides

3. Have a minimum bend radius of 4 inches

Manufacture mast arms from material specified for the standard.

Standards and poles must be straight with a maximum variation of:

1. 1 inch measured at the midpoint of a 30- to 35-foot standard

2. 3/4 inch measured at the midpoint of a 17- to 20-foot standard

Exposed edges of the plates that make up the base assembly must be finished smooth. Exposed corners of the plates must be broken. Provide shafts with slip-fitter shaft caps.

Surface flatness requirements specified in ASTM A6/A6M apply to plates meeting one or more of the following:

1. In contact with concrete, grout, or washers and leveling nuts

2. In HS bolted connections

3. In joints where cap screws are used to secure luminaire and signal arms

4. Used for breakaway slip base assemblies

Do not make additional holes in structural members.

Manufacture the cast steel option for slip bases from material of Grade 70-40 complying with ASTM A27/A27M. You may use other comparable material if authorized. Casting tolerances must comply with the Steel Founders' Society of America's recommendations for green sand molding.

56-3.02B(3)(c) Welding

Butt-welded circumferential joints of tubular sections requiring CJP groove welds must be made using a metal sleeve backing ring inside each joint. The sleeve must have at least a 1/8-inch nominal thickness and be manufactured from steel having the same chemical composition as the steel in the tubular sections to be joined. If the sections to be joined have different specified minimum yield strengths, the sleeve must have the same chemical composition as the tubular section having the higher minimum yield strength. The width of the metal sleeve must be consistent with the type of NDT selected and must be a minimum width of 1 inch. At fitting time, the sleeve must be centered at the joint and in contact with the tubular section at the point of the weld.

Welds must be continuous.

Weld metal at the transverse joints must extend to the sleeve, making the sleeve an integral part of the joint.

During manufacturing, longitudinal seams on vertical tubular members of cantilevered support structures must be within 90 degrees circumferentially of the center of the longest mast arm connection. Longitudinal seams on horizontal tubular members, including signal and luminaire arms, must be within 45 degrees of the bottom of the arm.

Longitudinal seam welds in steel tubular sections may be made by the electric resistance welding process.

Longitudinal seam welds must have a 60 percent minimum penetration except:

1. Within 6 inches of a circumferential weld, the longitudinal seam weld must be a CJP groove weld.

2. Longitudinal seam welds on lighting support structures having a telescopic pole segment splice must be CJP groove welds on the female end for a length on each end equal to the designated slip-fit splice length plus 6 inches.

Except for fillet and fatigue-resistant welds, exposed circumferential welds must be ground flush with the base metal before galvanizing or painting. Ground flush is specified as -0, +0.08-inch.

Circumferential welds and base plate-to-pole welds may be repaired only 1 time.

56-3.02C Construction

Assemble and tighten the slip base when the pole is on the ground. Threads of heavy hex nuts for each slip base bolt must be coated with additional lubricant that is clean and dry to the touch. Tighten HS slip base bolts to within ±10 ft-lb of torque shown in the following table:

Slip Base Bolt Tightening Requirements
Standard type	Torque (ft-lb)
15-SB	150
30	150
31	200

Bolted connections attaching signal or luminaire arms to poles are considered slip critical. Galvanized faying surfaces of plates on luminaire arms, signal arms, and poles must (1) be roughened by hand using a wire brush before assembly and (2) comply with requirements for Class C surface conditions for slip-critical connections in Specification for Structural Joints Using High-Strength Bolts of the RCSC. Coatings for faying surfaces must comply with the RCSC specification for Class B coatings.

56-3.02D Payment

Not Used

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