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Guardrail Materials meeting all applicable requirements of these specifications will be accepted on Brand Certification based on the requirements of North Carolina Department of Transportation's Brand Certification Program for guardrail materials as outlined in the Departments Materials and Tests Manual. The Department reserves the right to remove a manufacture of guardrail materials from the approved list in the event that the monitoring efforts indicate that non-specification material is being provided or tests procedures are not being followed.
1. The following types of guardrail materials and all associated accessories may be accepted under this program.
a) Rail elements.
b) Posts and offset blocks
c) Terminal sections
d) Anchor units
e) Transition sections
f) Hardware
The rail element and terminal sections shall meet the requirements of AASHTO M180 for Class A, Type 2.
1046-3 POSTS AND OFFSET BLOCKS.
(A) General:
The Contractor may, at his option, furnish any one of the following types of guardrail posts except where only one type is permitted by the plans. Only one type of post will be permitted at any one continuous installation, except that timber posts may be used with steel posts when steel posts are required by the plans at culverts or bridges.
1. Steel W6 x 8.5 or W6 x 9.0 posts.
2. Steel 4.5" x 6.0" "C" shape posts.
3. Timber 6" x 8" posts.
4. Timber 8" x 8" posts.
(B) Structural Steel Posts:
Steel posts for guardrail of the size and weight shown on the plans shall be fabricated from structural steel complying with the requirements of Section 1072, except that the metal from which C shape posts are fabricated shall meet the requirements of ASTM A570 for any grade of steel other than mechanical requirements which shall meet the requirements of ASTM A36. The holes for connecting bolts shall be punched or drilled. Burning will not be permitted. After fabrication the posts shall be galvanized in accordance with Section 1076.
(C) Treated Timber Posts:
All timber guardrail posts shall be of treated southern pine meeting the requirements of Article 10822 and 10823.
Bolt holes shall be bored to a driving fit for the bolts. A minus tolerance of 1 percent will be allowed in the length of the post. All framing and boring shall be done before the posts receive preservative treatment.
(D) Offset Blocks:
The offset blocks shall meet the same requirements as the posts.
All hardware shall be as indicated on the plans and shall be galvanized in accordance with ASTM A153.
1046-5 ANCHORS AND ANCHOR ASSEMBLIES.
The requirements of Articles 10461, 10462, and 10463 shall be applicable to rail elements, terminal sections, posts, offset blocks, and hardware.
Reinforcing steel shall meet the requirements of Article 10702. Steel plates shall meet the requirements of ASTM A36. Anchor rods shall meet the requirements of ASTM A663 for Grade 65.
Anchor cable shall be 3/4 inch wire rope having a minimum breaking strength of 21.4 tons and shall be galvanized. Cable thimbles shall be commercial quality galvanized steel. Cable clips shall be commercial quality drop forged galvanized steel. The fitting and stud for the anchor cable shall be suitable for cold swaging and shall be galvanized. After being swaged on the cable, the fitting and stud assembly, including swaged joint and cable, shall have a minimum breaking strength of 21.4 tons.
Welding shall be done in accordance with Article 107220.
Welded components shall be galvanized after welding in accordance with ASTM A123. All other metal parts shall be galvanized in accordance with ASTM A153, except where otherwise specified in Articles 10461, 10462, and 10463.
Repair of galvanizing shall be in accordance with Section 10876.
Acceptance of guardrail materials and its accessories will be based on, but not limited to, visual inspections, classification requirements, check samples taken from material delivered to the project, and conformance to the annual Brand Registration.
Guardrail materials not meeting the above requirements will be
rejected, unless written approval is obtained from the State Materials
Engineer.