Section 556 — Bridge Railing

Description

556.01This work consists of providing, erecting, removing, and resetting bridge railings.

Material

556.02Conform to the following Subsections: Aluminum alloy for bridge rail 717.10 Aluminum bolt heads and nuts 717.11 Aluminum welding wire 717.12 Box beam rail 724.01(b)

Construction Requirements

556.03General. Accurately place anchor bolts to provide correct and true alignment of the railing. Set anchor bolts so that they project no more than ⅜ inch beyond the nut when tightened. Cham fer or round by grinding or filing sharp exposed metal edges. Do not erect railing until centering or falsework for the supporting span is removed. Construct bridge railing so that it does not follow unevenness in the curb, sidewalk, or wall that supports the railing. Install railing to present a smooth and uniform appearance in its final position. Set posts vertical.

556.04Concrete Railing. Conform to Section 552. Construct reinforcing steel according to Section 554.

556.05Steel Railing. Conform to Section 555.

556.06Aluminum Railing. Conform to Section 555, except as modified by the following:

(a)Cutting. Material that is ½ inch thick or less may be cut by shearing, sawing, or milling. Saw or mill material that is over ½ inch thick. Do not flame cut. Make cut edges true, smooth, and without excessive burrs or ragged breaks. Fillet reentrant cuts by drilling before cutting.

(b)Bending. Material may be heated to a maximum 400 °F for no more than 30 minutes to facilitate bending. (c) Rivet and bolt holes . Drill rivet and bolt holes to finished size or subpunch smaller than the nominal diameter of the fastener and ream to size. Subpunch to a diameter that is smaller than that of the finished hole by at least one -quarter the thickness of the piece. Make the finished diameter of holes no more than 7 percent greater than the nominal diameter of the fastener, except:

(1)Fabric ate slotted bolt holes as required; and

(2)Fabricate anchor bolt holes up to 25 percent larger, no more than ½ inch larger than the nominal bolt diameter.

(d)Welding. Weld according to AWS D1.2, Structural Welding Code - Aluminum .

(e)Contact with ot her material. Protect aluminum alloys that contact other material as follows:

(1)Aluminum alloys in contact with other metals. Coat the contacting surfaces with dielectric aluminum- impregnated caulking compound or place a synthetic rubber gasket between the surfaces.

(2)Aluminum alloys in contact with stone or concrete.

(a)If a bond is not required, coat the contacting surfaces with aluminum -impregnated caulking compound or with heavy bituminous coating pigmented with aluminum powder or paste.

(b)If a bond is required, coat the contacting aluminum surface with zinc -chromate coating. Allow coating to dry before installation.

(3)Aluminum alloys in contact with wood. Coat the contacting wood surface with three coats of coating material according to Section 563 and coat the contacting aluminum surface with aluminum- impregnated caulking compound.

556.07Timber Railing. Conform to Section 557.

556.08Remove and Reset Bridge Railing. Salvage the existing bridge railings and appurtenances according to Subsection 203.04. Reset bridge railings as shown in the plans. Replace railings, supports, and hardware damaged during removal, storage, or resetting. 556.09 Coating. Conform to Section 563.

556.10Acceptance. Material (except concrete, coating, reinforcing steel, structural steel, and timber) for bridge railings will be evaluated under Subsections 106.02 and 106.03. Submit a production certification with each shipment of bridge railing. Construction of bridge railings will be evaluated under Subsections 106.02 and 106.04. Coatings will be evaluated under Section 563. Concrete will be evaluated under Section 552, except compressive strength will be evaluated under Subsection 106.04. Reinforcing steel will be evaluated under Section 554. Steel structures will be evaluated under Section 555. Timber structures will be evaluated under Section 557.

Measurement

556.11Measure the Section 556 pay items listed in the bid schedule according to Subsection 109.02 .

Payment

556.12The accepted quantities will be paid at the contract price per unit of measurement for the Section 556 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05 .