SECTION 1109 — GUIDE RAIL AND METAL MEDIAN BARRIER

1109.01RAILS — As shown on the Standard Drawings and as follows:

(a) Rail Elements. AASHTO-Ml80, Class A, Type 2; mark to show the approximate radius of curved rails.

(b) Rubbing Rails. Fabricate from steel, ASTM-A570, with mechanical properties in accordance with AASHTO-M270 (ASTM-A709) Grade 36.
Galvanize as specified in Section 1105.02(s) (AASHTO-M111).
Shop form, when required, on curves having a radius of less than 150 feet, as follows:

• Notch flanges to form a curve with a series of chords of equal lengths not exceeding 1 foot 6 inches (for radii from 0 to 20 feet), 3 feet (for radii from 20 to 100 feet), and 6 feet 3 inches (for radii from 100 to 150 feet); cut notches to the proper angle and weld.
• Form so the midpoint of the chord is tangent to the curve.
• Mark to show the approximate radius of curvature.

1109.02 TERMINAL SECTIONS — As shown on the Standard Drawings and as follows:

(a) Alternate Terminal Sections. AASHTO-Ml80, Class A, Type 2

(b) Terminal Section Bridge Connection. AASHTO-Ml80, Class B, Type 2

(c) Flared Terminal Section. AASHTO-Ml80, Class A, Type 2

1109.03 POSTS-

(a) Steel I-Beam Posts. AASHTO-M270 (ASTM-A709), Grade 36 or ASTM-A769.
Galvanize as specified in Section 1105.02(s) (AASHTO-M111).

(b) Steel C-Posts and Channel Posts. Fabricate from steel, ASTM-A570, with mechanical properties in accordance with AASHTO-M270 (ASTM-A709), Grade 36.
Galvanize as specified in Section 1105.02(s) (AASHTO-M111).

(c) Breakaway Cable Terminal Posts. AASHTO-M270 (ASTM-A709), Grade 36.
Galvanize as specified in Section 1105.02(s) (AASHTO-M111).

(d) Breakaway Cable Terminal Foundation Posts.

• Posts and 1/4-inch plates, as specified in Section 1109.05(b).
• Base plates, as specified in Section 1109.05(b).

(e) Breakaway Cable Terminal Foundation Anchor Plates. Section 1109.05(b)

1109.04 OFFSET BRACKETS — As shown on the Standard Drawings, using the same type of material and treatment as the posts to which the brackets are to be attached.

1109.05 MISCELLANEOUS MATERIAL — As shown on the Standard Drawings and as follows:

(a) Nuts, Bolts, and Washers. Section 1105.02(c)1.
Galvanize as specified in Section 1105.02(s) (ASTM-A153 or ASTM-B695 and B696).

(b) Base Plates, Post Plates, End Post Support Angles, and Hardware. AASHTO-M270 (ASTM-A709), Grade 36.
Galvanize base plates and hardware after fabrication, as specified in Section 1105.02(s) (AASHTO-M111). Do not punch, drill, grind, cut, or weld after galvanizing. Repair minor abrasions of galvanized surfaces with two coats of galvanizing paint.

(c) Breakaway Cable Terminal Hardware, Anchor Plate, and Cable Assembly.

• High-strength bolts, nuts, and washers, as specified in Section 1105.02(d).
• Galvanize cable assembly and bolts, nuts, and washers as specified in Section 1105.02(s) (ASTM-A153).
• Anchor plates, as specified in Section 1109.05(b).
• Cable assembly with a minimum breaking strength of 40,000 pounds.

(d) Rotating Bracket. Fabricate from malleable cast iron, ASTM-A47 or structural steel, AASHTO-M270 (ASTM-A709), Grade 36.
Galvanize as specified in Section 1105.02(s) (AASHTO-M111).

(e) Steel Spacer Tube. ASTM-A53, Type S, Grade B, plain end, Schedule 40 steel pipe.
Galvanize as specified in Section 1105.02(s).

1109.06 GALVANIZING — Galvanize metal parts as specified in Section 1105.02(s) (ASTM-A153 unless otherwise specified) and meet the requirements of AASHTO-M180, Section 9.

1109.07 GALVANIZING PAINT — Bulletin 26

1109.08 WELDING MATERIAL — Section 1105.02(t)

1109.09 CERTIFICATION — Section 106.03(b)3.

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