911.1General Description
This section includes the requirements for the following: • Galvanized steel sign posts • Galvanized steel structural shape posts • Aluminum structural shape posts • Delineator posts • Wood sign posts • Ground-mounted breakaway sign supports 911.1.01 Related References
ASTM A 1 A 123/A 123M A 153/A 153M A 193/A 193M A 307 A709/A 709M A 499 A 653/A 653M B 209 (B 209M) B 211 (B 211M) B 221 (B 221M) B 308 (B 308M) B 695 B 766 G 53 AASHTO M 181, Section 32 ANSI B 1.13M ANSI B 18.22.1 AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaires, and Traffic Signals (current edition) Georgia Standard No. 9055 Southern Pine Inspection Bureau Grading Rules, 1977 Edition NCHRP 350 QPL 29 QPL 35 QPL 69 1740
911.2Materials
911.2.01 Galvanized Steel Sign Posts (Drive Type)
Use drive-type steel posts made of flanged “U” channel or square tubular sections. For a list of sources, see QPL 35.
Use U-channel posts made of rerolled rail steel or new billet steel that meets the mechanical requirements of ASTM A 499, Grade 60, and the chemical requirements of ASTM A 1 for rails with nominal weights of 91 lbs./yd (45 kg/m) or greater.
posts, unless otherwise indicated on the plans. 1) Use post lengths as specified on the plans. 2) Use post assemblies within a sign structure from the same manufacturer. TABLE 1—DIMENSIONS, WEIGHTS, AND TOLERANCES FOR GALVANIZED STEEL SIGN POSTS (DRIVE TYPE) Outside Diameters TP 1 in. (mm) TP 2 in. (mm) TP 3 in. (mm) TP 4 in. (mm) Tolerance in. (mm) Flange Width
2.063 (50) 2.313 (60) 3.125 (80) 3.125 (80) 3.5 (90) 3.5 (90) 3.75 (95) 3.75 (95) ± 0.125 ( ± 3) ± 0.125 (± 3) Depth of “U”
0.875 (22) 0.875 (22) 1.500 (40) 1.500 (40) 1.875 (50) 1.750 (45) 2.000 (50) 1.750 (45) ± 0.125 (± 3) ±0.125 (± 3) Weight per linear foot (meter) before drilling, punching holes, or galvanizing)
1.12 lbs. (1.7 kg) 1.12 lbs. (1.7 kg) 2 lbs. (3 kg) 2 lbs. (3 kg) 3 lbs. (4.5 kg) 3 lbs. (4.5 kg) 4 lbs. (6 kg) 4 lbs. (6 kg) ± 5% ± 5%
1) Holes are 3/8 in. (10 mm) diameter and spaced 1 in., ±1/32 in. (25 mm, ± 1 mm), center to center. 2) Ensure that the holes start 1 in. (25 mm) from the top and extend the full length of the post for Types II, III, and IV, and at least 18 in. (450 mm) for Type I. 3) The Department will not accept field-punched holes.
or drilled.
Use square tubular posts that meet the requirements of ASTM A 653/A 653M, Structural Steel, Grade 50, Class 1 (Grade 340, Class 1).
square tubular posts unless otherwise indicated on the plans: 1741
TABLE 2—DIMENSIONS, WEIGHTS, AND TOLERANCES FOR SQUARE TUBULAR POSTS TP 5 TP 6 TP 7 TP 8 TP 9 Tolerance Outside size, in. (mm) 1.000 (25) 1.7 50 0(45) 2.000 (50) 2.500 (63) 2.250 (57.2) ± 0.010 (0.3) Wall thickness, in. (mm) 0.0 65 (1.7) 0.083 (2.1) 0.083 (2.1) 0.105 (2.7) 0.083 (2.1) ± 0.010 (0.2) Weight before drilling/ punching holes or galvanizing, lbs./ft. (kg/m) 0.83 (1.2) 1.8 (2.7) 2.1 (3.1) 3.4 (5.1) 2.27 (3.4) ± 5% 1) Use post lengths as specified on the plans. 2) Use post assemblies within a sign structure from the same manufacturer.
1) Holes are 7/16 in., ± 1/64 in. (11 mm, ± 0.5 mm) diameter and spaced 1 in., ± 3/64 in. (25 mm, ± 1 mm) center to center. 2) Ensure that the holes start 1 in. (25 mm) from the top and extend the full length of the post on all four sides for Types 6, 7, and 8, and at least 18 in. (450 mm) on all four sides for Type 5. 3) The Department will not accept field-punched holes.
Use bolts, nuts, metallic washers, and spacers made of aluminum, stainless steel, or galvanized steel. Use stainless steel that meets the requirements of ASTM A 193/A 193M, Type B8.
least 0.25 in. (6 mm) beyond the nut when installed. 1) Use a bolt thread fit of ANSI B 1.13M, Class 6H. 2) If using aluminum bolts, ensure that the aluminum meets the requirements of ASTM B 211 (B 211M), Alloy 2024-T4.
1) Use a bolt thread fit of ASNI B 1.13, Class 6G. 2) If using aluminum bolts, ensure that the aluminum meets the requirements of ASTM B 211(B 211M), Alloy 2017-T4.
and the sign face. 1) If using aluminum washers, ensure that the aluminum meets the requirements of ASTM B 209 (B209M), Alloy 2024-T4. 2) Use aluminum washers with 25/64 in. (10 mm) inside diameter, 0.75 in. (19 mm) outside diameter, and 0.091 in. (2.3 mm) thick. 3) Use standard galvanized and stainless steel washers that meet the size requirements of ANSI B
18.22.1
4) Use nylon washers with 13/32 in. (10 mm) inside diameter, 13/16 in. (21 mm) outside diameter, and 1/16 in. (1.6 mm) thick. Use nylon washers in combination with metallic washers to prevent torsional damage caused by the twisting action of the bolt heads.
1742
Get approval for each sign support matrix from the FHWA. The FHWA evaluates the matrix according to the AASHTO Standard Specifications for Structural Supports for Highway Signs, Luminaries, and Traffic Signals, current edition.
General Provisions 101 through 150. 911.2.02 Galvanized Steel Structural Shape Posts
hole during galvanizing.
General Provisions 101 through 150.
General Provisions 101 through 150.
General Provisions 101 through 150. 911.2.03 Aluminum Structural Shape Posts
NOTE: Use aluminum that meets the requirements of ASTM B 308/B 308M, Alloy 6061-T6.
General Provisions 101 through 150.
General Provisions 101 through 150.
General Provisions 101 through 150. 1743
911.2.04 Delineator Posts
Qualified Products List.
Fasten all delineators to be mounted on galvanized or aluminum posts with commercial aluminum lock bolts. NOTE: Fasten delineators to be mounted on wood posts with galvanized wood screws.
Use posts that meet the requirements of Subsection 911.2.02.A.
Use aluminum that meets the requirements of ASTM B 221 (B 221M), Alloy 6063-T6.
of the post.
Use 4 in. (100 mm) square posts of the length specified on the plans.
Use posts made of a durable plastic or poly resin material. Check the plans to see the type of flexible delineator post used for each location.
damage the posts or reflective sheeting, or be surface-mounted onto pavement. 1) Drill or form pilot holes where necessary to embed the posts as shown on the plans. 2) Classify flexible delineator posts as follows: Type I A B Curved or flat Soil mount Surface mount Type II A B Tubular Soil mount Surface mount 3) Use durable, flexible, non-discoloring posts that can recover from repeated vehicle impacts. 4) Ensure that materials used to manufacture flexible delineator posts are stabilized with UV (ultraviolet) inhibitors to prevent degradation. 5) Ensure that the posts are inert to normal atmospheric elements and chemicals possibly used in grass or weed control. 6) Use material for the post that can accept reflective sheeting. 1744
Use sheeting that meets the requirements of Subsection 913.2.01, Type III. Obtain approved reflective sheetings from QPL 29.
of the same material as when tested by National Transportation Product Evaluation Program (NTPEP) and will meet the requirements of this specification.
General Provisions 101 through 150.
Get approval for flexible delineator posts through the evaluation performed by NTPEP. The Department will use the data generated by the NTPEP testing to select usable materials that performed satisfactorily when tested with the following material and field tests.
at least a 3 in. (75 mm) wide profile facing approaching traffic.
corrosion-resistant material. When a post is no longer serviceable, remove it and replace it in the same anchor base.
ground for the soil mount flexible delineator posts is 48 in. (1200 mm).
when the existing post is no longer serviceable. Use post heights of 24 in. (600 mm), 36 in. (900 mm), or
48 in. (1200 mm), as required.
without significant color change or physical deterioration. If the Department sees splitting, cracking,
delaminating, or other failures, it will reject the delineator post.
Perform impact tests on the flexible delineator posts as described below:
in 1 pass of the vehicle.
reflective sheeting facing the test vehicle.
sharp hood ornaments or other appurtenances.
ambient temperature of 85 °F, ± 5 °F (30 °C, ± 2 °C). 1745
anchored, and return to their original vertical orientation within an angle of ±10 degrees.
sheeting and show minimal signs of distress (cracking, loss of rigidity).
requirements on the approved list.
General Provisions 101 through 150.
911.2.05 Wood Sign Posts
Standard No. 9055.
requirements for No. 1 SR or No. 2 SR as specified in the current Southern Pine Inspection Bureau Rules.
General Provisions 101 through 150.
General Provisions 101 through 150.
General Provisions 101 through 150.
911.2.06 Ground Mounted Breakaway Sign Supports
foundation. For a list of sources, see QPL 63.
Furnish a copy from the manufacturer of an independent testing agency report showing that the support has
been dynamically tested according to AASHTO Standard Specifications for Highway Signs, Luminaires, and
Traffic Signals, current edition.
as stated in Subsection 106.05, Materials Certification.
and Project conditions to the satisfaction of the Department.
above ground.
above ground. 1746
above ground.
approved equal.
Department Projects.
ASTM B 766 Type II, class 12-, whichever is applicable.
General Provisions 101 through 150.
Use foundation assemblies that are FHWA-approved for the specific design category for which the unit
was evaluated.
Foundation assemblies are evaluated according to AASHTO Standard Specifications for Highway Signs,
Luminaires, and Traffic Signals, current edition.
General Provisions 101 through 150.. 1747
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