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56-2.02 MATERIALS

56-2.02A General


Materials must comply with section 55.

Do not use weathering steel.


56-2.02B Bars, Plates, Shapes, and Structural Tubing

56-2.02B(1) General


Bars and plates must be structural steel complying with one or more of the following:

1. ASTM A36/A36M

2. ASTM A709/A709M, Grade 36 or 50

3. ASTM A572/A572M, Grade 50


Other open shapes must be structural steel complying with one or more of the following:

1. ASTM A36/A36M

2. ASTM A709/A709M, Grade 36 or 50

3. ASTM A992/A992M


Light fixture mounting channel must be continuous slot channel made from one of the following:

1. Steel complying with ASTM A1011/A1011M, Designation SS, Grade 33

2. Extruded aluminum of alloy 6063-T6 complying with ASTM B221 or B221M
Structural tubing and hollow structural sections must be structural steel complying with ASTM A500/A500M, Grade B or ASTM A1085.

Surface flatness after galvanizing must comply with ASTM A6/A6M for the following:

1. Base plates that are to come in contact with concrete, grout, or washers and leveling nuts

2. Plates in high-strength bolted connections



56-2.02B(2) Charpy V-notch Impact


Reserved

56-2.02C Sheets


Sheets must be carbon steel complying with ASTM A1011/A1011M, Designation SS, Grade 33.

56-2.02D Bolted Connections


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

Components of HS bolts must comply with section 55 for high strength steel fastener assemblies unless the bolts are shown to be snug tight. Bolts, nuts, and washers for HS bolts shown to be snug tight must comply only with section 55-1.02D(1).

Anchor bolts must comply with ASTM F1554, Grade 55, weldable steel.

Use a permanent steel template to maintain the proper anchor bolt spacing.

Provide 1 top nut, 1 leveling nut, and 2 washers for the upper threaded portion of each anchor bolt.

56-2.02E Anchorages


Anchorages for bridge mounted sign structures must comply with the specifications for concrete anchorage devices in section 75-3.

56-2.02F Pipe Posts


Pipe posts must be welded or seamless steel pipes. Pipe posts must comply with one of the following:

1. ASTM A53/A53M, Grade B

2. ASTM A106/A106M, Grade B

3. API Specification 5L PSL2 Grade B, Grade X42R or Grade X42M using nominal pipe sizes for threaded end pipe


You may fabricate posts from structural steel complying with ASTM A36/A36M.

Spiral seam welds are not allowed.


56-2.02G Steel Walkway Gratings


Steel walkway gratings must comply with the following:

1. Gratings must be the standard product of an established grating manufacturer

2. Material for gratings must be structural steel complying with ASTM A1011/A1011M as specified for Designation CS, Type B or Designation SS, Grade 36, Type 1

3. For welded type gratings, each joint must be full resistance welded under pressure to provide a sound, completely beaded joint

4. For mechanically locked gratings:

4.1. Method of fabrication and interlocking of the members must be authorized

4.2. Fabricated grating must be equal in strength to the welded type

5. Gratings must be accurately fabricated and free from warps, twists, or defects affecting their appearance or serviceability including:

5.1. Ends of all rectangular panels must be square

5.2. Tops of the bearing bars and cross members must be in the same plane

5.3. Gratings distorted by the galvanizing process must be straightened

56-2.02H Elastomeric Bearing Pads


Elastomeric bearing pads must comply with section 51-3.02.

56-2.02I Safety Chain at Walkways


Safety chain at walkways must comply with ASTM A413/A413M, Grade 43. The nominal chain size must be 1/4 inch. Use the minimum length that allows lock-up of safety railing.

56-2.02J Safety Cable at Walkways


Safety cable at walkways must:

1. Be constructed of Type 302 or 304 stainless steel 7 by 19 wire strand core cable

2. Have a cable breaking strength of at least 10,000 lb

3. Not be prestretched



56-2.02K Fabrication

56-2.02K(1) General


Sign structures must be:

1. Free from kinks, twists, or bends

2. Uniform in appearance
Fabricate sign structures into the largest practical sections before galvanizing.

Assemble the completed sections in the shop. Check sections for straightness, alignment, and dimension. Correct any variation.

Affix clips, eyes, and removable brackets to all signs and all posts for securing the sign during shipping, lifting, moving, and erection. Secure the sign as necessary to prevent damage to the finished galvanized or painted surfaces.

Do not make any holes in members unless the holes are shown or authorized.

Form the posts for tubular sign structures to the radii shown by heat treatment or by fabrication methods that will not:

1. Crimp or buckle the interior radius of the pipe bend

2. Change the physical characteristics of the material

56-2.02K(2) Welding


PJP longitudinal seam welds for tapered tubular members must have at least the minimum penetration shown but not less than 60 percent penetration. Within 6 inches of circumferential welds, longitudinal seam welds must be CJP groove welds. Longitudinal seam welds on structures with telescopic splices connecting pole segments must be CJP groove welds on the female end with a length equal to the designated slip-fit splice length plus 6 inches.

Except for welds at posts shown as PJP welds, longitudinal seam welds of fabricated pipe posts must be CJP groove welds.

The length of telescopic slip-fit splices must be at least 1.5 times the inside diameter of the exposed end of the female section.

Without authorization, you may make 1 repair to circumferential welds and to base plate-to-post welds. Obtain authorization before making any additional repairs.


56-2.02K(3) Bolted Connections


Except for HS bolts shown to be snug-tight, HS bolted connections must be HS assemblies complying with section 55-1.02E(6) except assemblies must consist of:

1. HS steel bolts

2. Nuts

3. Hardened washers



4. Direct tension indicators
HS fastener assemblies and any other bolts, nuts, and washers attached to sign structures must be zinc-coated by the mechanical deposition process.

Nuts for HS bolts at joints designated as snug-tight must not be lubricated.

Use an alternating snugging and tensioning pattern for anchor bolts and HS bolted splices. Once tensioned, do not reuse HS fastener components.

For bolt diameters less than 3/8 inch, the diameter of the bolt hole must be not more than 1/32 inch larger than the nominal bolt diameter.

For bolt diameters greater than or equal to 3/8 inch, the diameter of the bolt hole must be not more than 1/16 inch larger than the nominal bolt diameter.

56-2.02K(4) Walkway


Safety cable at walkways must be continuous between lugs. Before tightening cable clips at the end anchorage, remove the slack in the cable.

Safety cable at walkways must not be kinked, knotted, deformed, or spliced.

Install clips at safety cables under the manufacturer's instructions.

56-2.02K(5) Handholes


The edges of handholes and other large pole openings must be ground smooth. The roughness of edges must be less than 0.001 inch.

56-2.02K(6) Identification Plate


Permanently attach an aluminum identification plate near the base using either stainless steel rivets or stainless steel screws. Attach the plate adjacent to the traffic side on 1 of the vertical posts.

The information on the plate must include:

1. Name of the manufacturer

2. Date of manufacture

3. Contract number

56-2.02L Surface Finish

56-2.02L(1) General


Galvanize all ferrous metal parts of the following sign structure types:

1. Truss


2. Bridge mounted

3. Tubular


Except for tubular type sign structures, do not paint sign structures.

Clean and paint all ferrous metal parts of tubular sign structures after galvanizing, including the areas to be covered by sign panels.

Do not treat galvanized surfaces with chemicals before cleaning and painting.

Galvanize and do not paint walkway gratings, walkway brackets, gutters, safety railings, steel mountings for light fixtures, and all nuts, bolts, and washers for sign structures after fabrication.


56-2.02L(2) Galvanizing


Galvanizing must comply with section 75-1.02B except surfaces may be coated with zinc by the thermal spray coating process if authorized.

If authorized to use thermal spray coating, apply the coating under section 59-5. The thickness of the sprayed zinc coat must be at least 5 mils.

Do not use zinc solders or zinc alloys that contain tin to repair a damaged galvanized surface.

56-2.02L(3) Cleaning and Painting


Where specified, clean and paint sign structures under section 59-4.



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