602Reinforcing Steel

Reinforcing Steel

Description

602.01This work consists of furnishing and placing reinforcing steel per these specifications

and in conformity with the plans.

Materials

602.02Reinforcing steel and welded wire fabric that will be furnished either uncoated or epoxy

coated shall meet the requirements of subsection 709.01. The coating material shall be a light-colored powdered epoxy resin that will highlight rusting of untreated bar areas.

Reinforcing steel that requires welding shall conform to ASTM A706. Welding shall be done per ANSI/AWS D1.4.

All accessories, including reinforcing steel supports, ties, and splicers used in conjunction with reinforcing steel, shall be of the same, or compatible, coating as the reinforcing utilized.

Reinforcing steel not identified on the plans as epoxy coated may be supplied as epoxy coated, at the Contractor's option, at no additional cost to the Department. Epoxy coated reinforcing steel may not be substituted for Stainless, Continuous Hot dipped Galvanized, Zinc Coated (Galvanized), and Chromium reinforcing alternatives.

Reinforcing alternatives such as Stainless, Continuous Hot dipped Galvanized, Zinc-Coated (Galvanized), and Chromium reinforcing may be supplied for reinforcing steel or epoxy coated reinforcing, at the Contractor's option, at no additional cost or time to the Department as approved by the Engineer.

Length of lap splices for epoxy-coated reinforcing steel shall be per AASHTO LRFD Bridge Design Specifications, unless otherwise specified.

Construction Requirements

602.03Bar List. Two copies of a list of all reinforcing steel and bending diagrams shall be

furnished to the Engineer at the site of the work at least one week before the placing of reinforcing steel is begun. Such lists will not be reviewed for accuracy. The Contractor shall be responsible for the accuracy of the lists and for furnishing and placing all reinforcing steel per the details shown on the plans. Bar lists and bending diagrams that are included on the plans, do not have to be furnished by the Contractor. When bar lists and bending diagrams are included on the plans, they are intended for estimating approximate quantities. The Contractor shall verify the quantity, size, and shape of the bar reinforcement against those shown on the plans and make all necessary corrections before ordering.

602.04Protection of Materials. Reinforcing steel and its coating shall be protected at all

times from damage. When placed in the work, the reinforcing steel shall be free from dirt, loose mill scale, paint, oil, loose rust, or other foreign substance.

602.05

602.05Bending. Unless otherwise permitted, all reinforcing bars shall be bent cold. Bars

partially embedded in concrete shall not be field bent except as shown on plans or permitted. Bars shall not be bent or straightened in a manner that will injure the material or the epoxy coating. Should the Engineer approve the application of heat for field bending reinforcing bars, precautions shall be taken to assure that the physical properties of the steel will not be materially altered. Hooks and bends shall conform to the provisions of the AASHTO LRFD Bridge Design Specifications.

Bars that are shown as “hooked” on the plans shall have “standard hooks” unless otherwise indicated. The term “standard hook” as used shall mean one of the following:

free end of the bar, or

end of the bar.

of the bar.

end of the bar. The inside diameter of bend measured on the inside of the bar, other than for stirrups and ties, shall be as follows:

Table 602-1 Tension Bar Bending Radii

Bar Size Grade 60 No. 3 thru No. 8 6 bar diameter No. 9, No. 10, and No. 11 8 bar diameter No. 14 and No. 18 10 bar diameter

The inside diameter of bend for stirrups and ties shall not be less than four bar diameters for sizes No. 5 and smaller, and five bar diameters for No. 6 to No. 8 inclusive.

Inside diameter of bend in welded wire fabric, smooth or deformed, shall not be less than four wire diameters for deformed wire larger than D6 and two wire diameters for all other wires. Bends with an inside diameter of less than eight wire diameters shall not be less than four wire diameters from the nearest welded intersection.

602.06Placing and Fastening. The minimum spacing center to center of parallel bars shall

be 2 1/2 times the diameter of the bar. However, the clear distance between the bars shall not be less than 1 1/2 times the maximum size of the coarse aggregate or 1 1/2 inches, whichever is greater.

602.06

Bundle bars shall be tied together at not more than 6-foot centers. All reinforcement shall have a clear coverage of 2 inches, except as shown on the plans. Clear coverage shall be measured from the surface of the concrete to the outside of the reinforcement. Reinforcement used in post-tensioned concrete shall be adjusted or relocated during the installation of prestressing ducts or tendons, as required, to provide a location and planned clearances to the prestressing tendons, anchorages, jacks, and equipment as approved by the Engineer. All reinforcement shall be tied at all intersections except where spacing is less than 1 foot in each direction, in which case, alternate intersections shall be tied. In concrete bridge decks the upper mat of bars shall be tied to the lower mat of bars at a 4-foot maximum spacing in each direction. Slab bolsters for the bottom mat and highchairs for the top mat shall each be placed at a maximum spacing of 4 feet on centers. Welding on reinforcing bars will not be permitted except as noted on the plans. Reinforcement placed in any member shall be inspected and approved before any concrete is placed. The placing, fastening, splicing, and supporting of reinforcing steel and wire mesh or bar mat reinforcement shall be per the plans and the latest edition of Concrete Reinforcing Steel Institute (CRSI)’s “CRSI Recommended Practice for Placing Reinforcing Bars.” In case of discrepancy between the plans and the CRSI publication stated above, the plans shall govern. Automated tie wire devices may be used. The total cross-sectional area of the automated tie wire wrap shall roughly equal the total cross-sectional area of a manually installed tie wire wrap. The tie wire shall be epoxy coated or plastic coated for use with epoxy-coated reinforcing steel. All epoxy coating on the reinforcing steel that is damaged from the use of automated tie wire devices shall be repaired at the Contractor’s expense. Precast concrete blocking or other approved blocking material shall be used to support footing bars and bars in slabs on grade. All other reinforcing steel shall be supported with steel chairs or precast mortar blocks. All chairs coming in contact with forms shall be CRSI Class 1 or Class 2, Type B. The location of splices, except as shown on the plans, shall be based upon using 60-foot stock length bars for No. 6 bars and larger and 40-foot stock length bars for No. 4 and No. 5 bars (this does not preclude the use of 60 foot). Minimum splice lengths are as shown on the plans. Where bars of different sizes are spliced together, the splice length for the smaller bar will govern. Unless otherwise shown on the plans or approved, splices in adjacent lines of reinforcing bars shall be staggered. The minimum distance between staggered splices for reinforcing bars shall be the length required for a lapped splice in the bar. Lapped splices will be permitted only at locations where the concrete section is sufficient to provide a minimum clear distance of 2 inches between the splice and the nearest adjacent bar. The clearance to the surface of the concrete shall not be reduced. Reinforcing bars may be continuous at locations where splices are shown on the plans. Reinforcing bars No. 14 and No. 18 shall not be spliced by lapping, but shall be joined by butt welding, per AWS D1.4 in such a way as to develop at least 125 percent of the specified yield strength of the bar in both tension and compression. Alternate systems of welding or mechanical butt splices may be submitted for approval.

602.07

Method of Measurement

602.07The weight of reinforcing steel for payment will not be measured but shall be the

quantities designated in the Contract; except, measurements will be made for revisions requested by the Engineer, or for an error of plus or minus 2 percent of the total weight shown on the plans for each structure.

Prospective bidders shall verify the weight of reinforcing steel before submitting a proposal. An adjustment will not be made in the weight shown on the plans, other than for approved design changes or for an error as stipulated above, even though the actual weight may deviate from the plan weight.

The computed weight of epoxy-coated reinforcing bars will be based on the nominal weight before application of the epoxy coating. Nominal weights for various bar sizes are shown below.

Table 602-2 Nominal Weights for Bar Sizes

Bar Size Weight per Linear Foot Bar Size Weight per Linear Foot in Pounds in Pounds No. 8 2.67 1/4 inch 0.167 No. 9 3.4 No. 3 0.376 No. 10 4.303 No. 4 0.668 No. 11 5.313 No. 5 1.043 No. 14 7.65 No. 6 1.502 No. 18 13.6 No. 7 2.044 Basis of Payment

602.08The accepted quantities of reinforcing steel will be paid for at the contract unit

price per pound. No allowance will be made for supports, clips, wire, or other material used for fastening reinforcement in place. Payment will be made under: Pay Item Pay Unit Reinforcing Steel Pound Reinforcing Steel (Epoxy Coated) Pound Reinforcing Steel (Galvanized) Pound Reinforcing Steel (Stainless) Pound Reinforcing Steel (High Performance) Pound

602.09

Galvanic Anodes Description

602.09This work consists of furnishing and installing galvanic anodes, tying existing steel

reinforcing mats for electrical continuity, and testing for electrical continuity in concrete repair locations shown on the plans or as directed by the Engineer.

Materials

602.10Materials shall meet the requirements shown on the plans and in the following

subsections:

Galvanic Anodes shall be on the Department’s Approved Products List and meet the requirements of Subsection 709.04.

Concrete shall meet the requirements of Section 601.

Patching material shall have a minimum compressive strength of 4500 psi no later than 28 days or as designated on the plans and be on the Department’s Approved Products List.

Construction Requirements

602.11Placing Anodes. At least 10 working days before the start of repair work, the Contractor

shall submit documentation of the anode manufacturer’s approval of the patching concrete compatibility with their anode system and any special treatment requirements and installation requirements.

Anodes used with patching material having resistivity greater than 15,000 Ohm-Centimeters (Ohm-cm) or not meeting compatibility requirements shall be specially treated and installed per manufacturer recommendations such as grout encapsulation or bedding.

Galvanic anodes shall be installed per manufacturer’s requirements. Anodes shall be placed in each patch, 18 to 24 inches apart on the perimeter, based on rebar spacing as per Manufacturer’s requirements. A minimum of one anode shall be placed in each patch and may be placed in the middle of the patching material area if the spacing requirement cannot be met. Each anode shall have a minimum 1.5 inch top cover to the surface of the new concrete deck patch, a 1 inch minimum side cover and adequate vibration to insure good concrete flow on the bottom. Clear side covers less than 1 inch will require grout beds as shown in the drawings.

The steel reinforcement shall be cleaned to bright metal where the anode tie wire connection will be installed. Anodes and encapsulation grout (if necessary) shall be installed within 8 hours after the preparation and cleaning of steel reinforcement. Repair any damaged epoxy coating.

Galvanic anodes shall be secured with anode tie wires as close as possible to the patch edge while achieving minimum cover requirements. The tie wires shall be wrapped around the cleaned reinforcing steel and twisted tight to allow little or no free movement.

602.12

Before placing new concrete, galvanic anodes shall be installed per the manufacturer’s recommendations and inspected for proper connection and continuity to reinforcing steel.

Electrical connection and continuity between anode tie wire and reinforcing steel shall be confirmed by measuring DC resistance (ohm) or potential with a multi-meter. Electrical connection and continuity are acceptable if the DC resistance measured with a multimeter is less than 1 ohm or the DC potential is less than 1 mV.

All intersections of reinforcing steel at all patch locations shall provide electrical continuity. The Contractor shall confirm continuity of at least three intersections per repair area on each structure or as directed by the Engineer. Intersections with visible separation or lack of continuity shall be cleaned and tied with bare steel tie wire to achieve continuity. Additional continuity testing will be required as directed by the Engineer. Electrical continuity within a repair area is acceptable if the DC resistance measured with a multimeter is less than 1 ohm or the potential is less than 1 mV.

The Contractor shall furnish the Department with a multimeter to independently check the electrical connection. The multimeter shall become the property of the Department.

Method of Measurement

602.12Galvanic Anodes will be measured as the actual quantity installed and accepted

Basis of Payment

602.13The accepted quantities of Galvanic Anodes will be paid for at the contract unit

price.

Payment will be made under: Pay Item Pay Unit Galvanic Anodes Each

Payment for Galvanic Anodes will be full compensation for all labor, equipment, materials, and incidentals required to complete the item.

Electrical continuity tie wiring and testing will not be measured and paid for separately but shall be included in the work.

The multimeter will not be measured and paid for separately but shall be included in the work.

If additional anodes are required during construction, the additional anodes will be paid for at the original Contract unit price.

Any special treatment or installation of the anodes that is required by the anode supplier due to the type of patching material used, including but not limited to, grout beds between substrate and anode, or grout encapsulation of the anodes, will not be measured and paid for separately but shall be included in the work.

603.01