Section 554 — Reinforcing Steel

Description

554.01This work consists of providing and placing reinforcing steel.

Material

554.02Conform to the following Subsection: Reinforcing steel 709.01

Construction Requirements

554.03Order Lists. On reinforcing steel order lists, use the same respective bar marks for labeling as shown in the plans. Submit order lists and bending diagrams for approval. Approval does not relieve the Contractor of responsibility for the accuracy of the lists and diagrams. Do not order material until the lists and diagrams are approved. Do not fabricate vertical reinforcement in columns, walls, piers, and shafts until footing elevations are established in the field.

554.04Identification. Ship bar reinforcement in standard bundles, tagged and marked according to CRSI, Manual of Standard Practice . Provide the following information with each shipment of steel to the project:

(a)Name and location of the steel rolling mill;

(b)Manufacturing process;

(c)Heat numbers;

(d)Sizes;

(e)Specifications;

(f)Copies of mill test analyses for chemical and physical tests; and

(g)Consignee and destination of shipment.

554.05Bending. Fabricate reinforcing bars according to ACI SP -66, ACI Detailing Manual . Cold bend reinforcing bars that require bending. Limit the overall height or drop bending tolerance of deck truss bars to plus 0 inch or minus ¼ inch. Do not bend bars that are partially embedded in concrete, except as shown in the plans or otherwise allow ed. Provide standard hooks conforming to ACI SP-66.

554.06Protection of Material. Store reinforcing steel above the ground on platforms, skids, or other supports. Protect reinforcing steel from physical damage, rust, and other surface deterioration. Use reinforcing steel only when the surface is clean and the minimum dimensions, cross- sectional area, and tensile properties conform to the physical requirements for the size and grade of steel specified. Do not use reinforcing steel that is cracked, laminate d, or is covered with dirt, rust, loose scale, paint, grease, oil, or other deleterious material.

554.07Epoxy- Coated Reinforcing Steel. Support coated bars on padded contact areas. Lift with a strong back, spreader bar, multiple supports, or a platform bridge to prevent bar -to-bar abrasion. Do not drop or drag bundles. Before placement, inspect bars for coating damage. Replace and do not use bars with a total damaged area in any 12- inch length that is more than 5 percent of the surface area of that length of the bar. Clean other damaged coatings by removing surface contaminants and the damaged coating. Roughen the area around the damage and remove rust by blast cleaning or power tool cleaning. Patch defects in the coating that are discernible to the unaide d eye using a prequalified patching material conforming to ASTM A934 for epoxy- coated prefabricated reinforcement or ASTM A775 for epoxy -coated reinforcement. Overlap the patching material onto the original coating for 2 inches or according to the manufact urer’s recommendations. Provide at least 8 -mil dry film thickness on the patched areas. Take necessary steps to minimize damage to the coating of installed bars. Clean and patch damage to coatings noted after installation. Promptly treat the bar according to the resin manufacturer’s recommendations and before detrimental oxidation occurs. For epoxy- coated prefabricated reinforcement conforming to ASTM A934, coat mechanical splices after splice installation according to ASTM A934 for patching damaged epoxy coatings. For epoxy- coated reinforcement, coat mechanical splices after splice installation according to ASTM A775 for patching damaged epoxy coatings.

554.08Placing and Fastening. Place, fasten, and support the bars according to the CRSI, Manual of Standard Practice . Coat chairs, tie wires, and other devices used to support, position, or fasten epoxy- coated reinforcement with a dielectric material. Use precast concrete blocks or metal supports. Attach concrete block supports to the supported bar with wire cast in the center of each block. Use Class 1 (plastic protected) or Class 2, Type B (stainless steel protected) metal supports in contact with exposed concrete surfaces. Use stainless steel conforming to ASTM A493, Type 430. Space slab bar supp orts no more than 48 inches apart transversely or longitudinally. Do not use bar supports either directly or indirectly to support runways for concrete buggies or other similar construction loads. Replace damaged supports. Place bars no more than 1½ inches from the plan location. Do not cumulate spacing variations. Do not allow the average of any two adjacent spaces to exceed the required spacing. Place reinforcing steel in deck slabs within ¼ inch of the vertical plan location. Using a template, check the clear cover over deck reinforcing steel before placing deck concrete. Provide 2 inches clear cover for reinforcement. The tolerance on minimum concrete cover is minus ⅜ inch. For concrete surfaces cast against the ground provide at least 3 inches of clear cover over reinforcement. Tie reinforcing at intersections around the perimeter of each mat and at no more than 24 -inch centers or at every intersection, whichever is greater. Tie bridge deck reinforcing bars at no more than 12 inches or every intersection, whichever is greater. Tie bundle bars together at intervals no more than 6 feet. Do not bundle bars unless the location and splice details are specified. Do not place concrete in members until the reinforcing steel placement is approved.

554.09Splices. Do not splice, except as shown in the plans, without approval. Provide lap lengths shown in the plans. Make lapped splices by placing the reinforcing bars in contact and wiring them together to maintain the alignment and position of the bars. If welding of reinforcing steel is allowed, use welders with current certifications and weld according to AWS D1.4, Structural Welding Code – Steel Reinforcing Bars . Do not weld reinforcing steel conforming to AASHTO M 31 or corrosion- resistant reinforcing steel bars. Do not weld reinforcing steel if its carbon equivalent exceeds 0.55 percent. Mechanical couplers may be used if approved. Use couplers with a strength that is at least 125 percent of the required yield strength of the reinforcing steel. Do not exceed 0.01 inch total slip of the reinforcing bar within the splice sleeve when loading in tension to 30.0 kips per square inch and relaxing to 3.0 kips per square inch for bar sizes up to No. 14 as measured between gauge points clear of the splice sleeve. For mecha nical couplers used in the superstructure slab, use only butt type splices. Use only epoxy coated mechanical couplers for joining epoxy coated reinforcing. For corrosion -resistant steel reinforcing bars, use only mechanical butt couplers of the same material as the bars being spliced. Provide clear coverage at splice sleeves of at least 1.75 inches measured from the surface of the concrete to the outside face of the sleeve. Do not place slab bar mechanical splices adjacent to each other. Use mechanical spli ces according to the manufacturer’s recommendations. If welded wire fabric is shipped in rolls, straighten into flat sheets before placing. Splice sheets of mesh or bar mat reinforcement by overlapping at least 1 -mesh width plus 2 inches. Securely fasten a t the ends and edges.

554.10Acceptance. Reinforcing steel and epoxy coating material will be evaluated under Subsections 106.02 and 106.03. Provide a production certification with each shipment of reinforcing steel. Placement of reinforcing steel will be evaluated under Subsections 106.02 and 106.04.

Measurement

554.11Measure the Section 554 pay items listed in the bid schedule according to Subsection 109.02 and the following as applicable: Do not measure reinforcing steel laps added for the Contractor’s convenience. Do not measure reinforcing steel for precast, prestressed concrete structural members.

Payment

554.12The accepted quantities will be paid at the contract price per unit of measurement for the Section 554 pay items listed in the bid schedule. Payment will be full compensation for the work prescribed in this Section. See Subsection 109.05 .