Article 1 — Description
Construct railing of concrete, steel, aluminum, or a combination of these materials, including necessary anchorage for the railing on bridges, culverts, walls, or other structures as shown on the plans .
Article 2 — Materials
Use materials that conform to requirements of the following Items. Item 421, “Hydraulic Cement Concrete” Item 440, “Reinforcement for Concrete” Item 441, “Steel Structures” Item 442, “Metal for Structures” Item 445, “Galvanizing” Item 540, “Metal Beam Guard Fence” Provide an approved Type III, Class C epoxy or an epoxy of the type and class shown on the plans where epoxy anchors are allowed or required for installing drilled and epoxied rail anchorage reinforcement or rail anchor bolts in accordance with DMS -6100 , “Epoxies and Adhesives.” Use other materials if shown on the plans. Provide only dual -cartridge epoxy systems mixed with a static mixing nozzle supplied by the epoxy adhesive manufacturer and dispensed using a tool supplied by the epoxy adhesive manufacturer. Do not use bulk epoxies. Drill and install anchorage reinforcement or anchor bolts to the embedment depth shown on the plans or the depth the manufacturer recommends, whichever is deeper. No additional payment will be made for providing embedment deeper than shown on the plans. Select an embedment depth capable of developing the yield strength of the steel anchor based on the product literature for the epoxy and steel anchor being used if no resistance or embedment depth is shown on the plans. Use 60 ksi as the yield strength for reinforcing steel.
Article 3 — Construction
Construct railing in compliance with details, alignment, and grade shown on the plans. Do not place railing until falsework or formwork, if any, for the span has been released unless otherwise directed. Adhere to the schedule restrictions for placing bridge r ails and o pening to construction traffic in accordance with Item 422, “Concrete Superstructures.” Notify the Engineer after completion of the following steps and obtain approval of work before proceeding to the next step: placing rail reinforcement and pre- pour clear cover checks. Ensure expansion joints in the railing will function properly before placing concrete. Furnish either steel or aluminum, but not both, for the entire Contract if the plans allow either steel or aluminum options for a particular railing type. Install epoxy adhesive anchorages in conformance with the manufacturer’s instructions , including hole size, drilling equipment and method, hole cleaning equipment and method, mixing and dispensing epoxy, and anchor insertion. Do not alter the manufacturer’s mixing nozzle or dispenser. Anchorage bars or bolts must be clean and free of grease, oil, or any other foreign material. Demonstrate hole cleaning method to the Engineer for approval and continue the approved process for all anchorage locations. Do not weld to an anchor bar or anchor bolt that is anchored with epoxy adhesive. Do not expose rail to traffic until epoxy adhesive has obtained full cure in conformance with manufacturer’s specifications. 696 3.1. Metal Railing .
3.1.1 General . Furnish metal beam rail elements in accordance with Item 540.
Fabricate and erect metal railing in accord ance with the pertinent provisions of Item 441 and this Item . Prepare and submit for approval the required shop or erection drawings in accordance with Item 441 when shown on the plans. Show all splice locations and details on the shop or erection drawings. Splice members only as shown on the plans . Field -weld when required in accordance with Item 448, “Structural Field Welding.”
3.1.2 Fabrication . Fabrication plants that produce metal railing (steel and aluminum) must be approved in
accordance with DMS -7395 , “Metal Railing Fabrication Plant Qualification.” This required approval does not include fabricators of chain link fence. The Department maintains an MPL of approved fabrication plants of metal railing. Permanently mark each metal railing post base plate, at a visible location when erected, with the fabrication plant’s insignia or trademark. For fabricated rail panels, provide this permanent mark on one post base plate per panel. Fabricate metal railing and post panels in sections conforming to the details shown on the plans and field-verified lines and grades. Fabricate adjacent sections so they will accurately engage each other in the field. Match -mark each pair of sections so they can be erected in the same position in which they were fabricated. Fabricate metal rail elements included as part of the railing system to the dimensions and cross -sections shown on the plans and within a tolerance of 1/4 in. per 10 ft . in the straightness of either edge. C onnect metal rail elements to the rail posts as shown on the plans, lapping metal rail elements in the direction of traffic in the adjacent lane. Bolts and nuts for metal railing should meet requirements of ASTM A307 and be galvanized in accordance with Item 445, unless otherwise shown on the plans. Fabricate stainless steel railing in accordance with AWS D1.3. Fabricate aluminum railing in accordance with AWS D1.2. When required, heat aluminum materials to a temperature up to 400°F for no more than 30 min. to facilitate bending or straightening.
3.1.3 Corrosion Protection. Galvanize all portions of steel railing after fabrication in accordance with Item 445,
unless otherwise shown on the plans. Apply appearance coat to galvanized surface in accordance with Item 445 when shown on the plans. Repair any damage to galvanized or painted surfaces after erection in accordance with Item 445 and Item 446, “Field Cleaning and Painting Steel,” respectively. Before final acceptance, clean surfaces of aluminum and galvanized steel railing not shown to be painted to remove extrusion marks, grease, dirt, and all other surface contaminants.
3.1.4 Storage and Shipping. Store railing materials above the ground on platforms, skids, or other supports, and
keep them free of grease, dirt, and contact with dissimilar metals. Avoid scratching, marring, denting, discoloring, or otherwise damaging the railing. Properly ship railing materials in a manner to avoid damage.
3.2 Concrete Railing . Provide concrete portions of railing in accordance with the requirements of Item 420,
“Concrete Substructures,” and Item 422, “Concrete Superstructures.” Construct forms so the railing line and grade can be checked after the concrete has been placed but before initial set. Do not disturb the form alignment during finish floating of the railing tops. Exercise particular care in other construction to avoid disturbing or vibrating the span with the newly placed railing. 697 Provide precast members conforming to Item 424, “Precast Concrete Structural Members (Fabrication).” Slipform construction of railing is permitted unless otherwise shown on the plans. Demonstrate slipforming method showing line and grade of concrete surfaces can be consistently obtained and clear cover outside reinforcing steel be maintained at all times. Stop slipforming railing if specified concrete clear cover is not obtained or appearance of rail is off line and grade. Do not slipform railing with cast -in-place anchor bolts unless noted otherwise. Provide additional reinforcing as needed to prevent movement of the reinforcement cage. Clear cover and epoxy coating requirements for additional reinforcement are the same as those shown for the rail reinforcement. The rail reinforcing cage may be tack welded to the rail anchorage reinforcement provided the rail and anchorage reinforcement are not epoxy -coated and weld locations measured along the rail are no closer than 3 ft. Tie all bar intersections if epoxy -coated reinforcement is required for the railing proposed to be slipformed. Provide a wire line to maintain vertical and horizontal alignment of the slipform machine. Attach a grade line gauge or pointer to the machine so a continuous comparison can be made between the rail being placed and the established grade line. Rails or supports at the required grade are allowed instead of sensor controls. Make one or more passes with the slipform over the rail segment to ensure proper operation and maintenance of grades and clearances before placing concrete. Provide slipformed rail within a vertical and horizontal alignment tolerance of ±1/4 in. per 10 ft. Construct rail with a smooth and uniform appearance. Consolidate concrete so it is free of honeycomb. Provide concrete with a consistency that will maintain the shape of the rail without support. Minimize starting and stopping of the slipform operation by ensuring a continuous supply of concrete. Do not exceed the manufacturer’s recommended speed for the slipform machine. Stop slipforming and take remedial action if slipforming causes movement of the reinforcement such that plan clearances are not achieved. Remove and replace unsatisfactory slipformed rail at the Contractor’s expense.
3.3 Tests. Metal beam rail elements may be sampled in accordance with Tex -713-I
. The Engineer may sample bolts and nuts in accordance with Tex-708-I for galvanized coating testing. The Engineer will select five anchor bars or bolts from the first day’s production to be tested after the epoxy has cured. Test the bars or bolts in the presence of the Engineer in accordanc e with ASTM E1512, using a restrained test, to evaluate the epoxy adhesive’s bond strength. Verify the anchor bars or bolts develop the required pullout resistance on the plans or 75% of the yield strength of the bars or bolts, whichever is less, without a bond failure of the epoxy. The Engineer may require additional tests during production. Perform corrective measures to provide adequate capacity if any of the tests do not meet the required test load. Repair damage from testing.
Article 4 — Measurement
This Item will be measured by the foot. This is a plans quantity measurement Item. The quantity to be paid is the quantity shown in the proposal , unless modified by Article 9.2., “Plans Quantity Measurement.” Additional measurements or calculations will be made if adjustments of quantities are required.
Article 5 — Payment
The work performed and materials furnished in accordance with this Item and measured as provided under “Measurement” will be paid for at the unit price bid for “Railing” of the type specified. This price is full compensation for furnishing, preparing, and placing concrete, expansion joint material, reinforcing steel, structural steel, aluminum, cast steel, pipe, anchor bolts or bars, testing of epoxy anchors, and all other materials required in the finished railing; removal and disposal of salvageable materials; and hardware, paint and painting of metal railing, galvanizing, equipment, labor, tools, and incidentals.