M 41-10 Page 9-63 Reinforcing Steel 9-079-07 Reinforcing Steel
9-07.1 General
9-07.1(1) A cceptance by Manufacturer’s Certification
Reinforcing steel may be accepted by the Engineer based on the Manufacturer’s Certificate of Compliance.
9-07.1(1)A A cceptance of Materials
Reinforcing steel rebar manufacturers shall comply with the National Transportation Product Evaluation Program (NTPEP) Work Plan for Reinforcing Steel (rebar) Manufacturers. Reinforcing steel rebar manufacturers shall participate in the NTPEP Audit Program for Reinforcing Steel (rebar) Manufacturers and be listed on the NTPEP audit program website displaying that they are NTPEP compliant. Steel reinforcing bar manufacturers use either English or a Metric size designation while stamping rebar. The actual size of the bar, whether stamped with an English or a Metric size designation is acceptable. The Contract Plans and the Standard Plans will continue to use an English size designation. The table below shows the comparable reinforcing steel bar size designations in both units of measure: English Designation Bar Diameter Metric Designation #3 (0.375 inches) #10 #4 (0.500 inches) #13 #5 (0.625 inches) #16 #6 (0.750 inches) #19 #7 (0.875 inches) #22 #8 (1.000 inches) #25 #9 (1.128 inches) #29 #10 (1.270 inches) #32 #11 (1.410 inches) #36 #14 (1.690 inches) #43 #18 (2.260 inches) #57
9-07.1(2) Bending
Steel reinforcing bars shall be cut and bent cold to the shapes shown on the Plans. Fabrication tolerances shall be in accordance with ACI 315. The dimensions shown in the Plans are out-to-out unless shown otherwise. Hooks and bends of steel reinforcing bars shall be bent to the following inside diameters unless shown otherwise in the Plans: Bar Size Stirrups and Ties (in) All Other Bars No. 3 1½ 6 bar diameters No. 4 2 6 bar diameters No. 5 2½ 6 bar diameters No. 6 4½ 6 bar diameters No. 7 5¼ 6 bar diameters No. 8 6 6 bar diameters No. 9 through No. 11 8 bar diameters No. 14 through No. 18 10 bar diameters The supplementary requirements of AASHTO M31 for bend tests shall apply to size No. 14 and No. 18 steel reinforcing bars which have hooks or bends. Page 9-64 M 41-10
9-07 Reinforcing SteelHooked ends of steel reinforcing bars shall be standard hooks unless shown otherwise
in the Plans. Standard hooks shall consist of a 90-, 135-, or 180-degree bend as shown in the Plans plus a minimum bar extension at the free end of the bar shown in the table below. Seismic hooks shall consist of a 135-degree bend plus a minimum bar extension at the free end of the bar shown in the table below. Minimum Bar Extensions for Standard and Seismic Hooks Bar Size180º Hook 135º Hook 90º Hook All Bars Seismic HookAll Other BarsStirrups and TiesAll Other Bars No. 3 2 ½″ 3″ 2¼″ 2¼″ 4½″ No. 4 2 ½″ 3″ 3″ 3″ 6″ No. 5 2 ½″ 3¾″ 3¾″ 3¾″ 7½″ No. 6 3″ 4½″ 4½″ 9″ 9″ No. 7 3½″ 5¼″ 5¼″ 10½″ 10½″ No. 8 4″ 6″ 6″ 12″ 12″ No. 9 4¾″ 13¾″ No. 10 5¼″ 15¼″ No. 11 5¾″ 17″ No. 14 7″ 20½″ No. 18 9¼″ 27¼″
9-07.1(3) Lengths
Net length is the length of bar along the bar centerline from end to end. Net lengths of bent bars shown in the “LENGTH” column of the bar list in the Plans are rounded to the nearest inch.
9-07.1(4) Vacant
9-07.2 Deformed Steel Bars
Deformed steel bars for concrete reinforcement shall conform to either AASHTO M 31 Grade 60 or ASTM A706 Grade 60, except as otherwise noted in this section or as shown in the Plans. Steel reinforcing bars for the cast-in-place components of bridge structures, and for precast substructure components of bridge structures, shall conform to ASTM A706 Grade 60 only. Deformed steel bars are referred to in the Plans and Specifications by number: for example, No. 3, No. 4, No. 5, etc.
9-07.2(1) Headed Steel Reinforcing Bar
Headed steel reinforcing bars shall conform to Section 9-07.2 and ASTM A970, including Annex A1 requirements for Class HA head dimensions. Headed steel reinforcing bars shall be cold-swaged headed bars, forged headed bars or threaded headed bars.
9-07.3 Epoxy-Coated Steel Reinforcing Bars
Epoxy-coated rebar shall be coated according to ASTM A775 with the additional following modifications:
1.The list of steel reinforcing bars acceptable for coating shall include ASTM A706.
2.The Contractor shall furnish a written certification that properly identifies the material, the number of each batch of coating material used, quantity represented, date of manufacture, name and address of manufacturer, and a statement that the supplied coating material meets the requirements of ASTM A775. M 41-10 Page 9-65 Reinforcing Steel 9-073. Prior to coating the bars, the Contractor shall submit to the Engineer for review, the coating material manufacturer’s recommendation on the proper use and application requirements of the coating material. For Pre-approved Epoxy Coating Facilities, this information will be available to the Fabrication Inspector upon request.
4.A certification stating that all bars have been coated in accordance with the coating material manufacturer’s recommendations and these Specifications shall be furnished with each shipment. This certification shall include for each bar size the preheat temperatures, cure times, thickness checks, holidays detected, and test results. Two copies of these certifications shall be furnished to the Engineer.
5.The Contractor shall give advance notice to the Engineer of the coating schedule in the coating plant so that Contracting Agency inspection may be provided. The Engineer may inspect the coated bars at the coating plant for approval.
6.The patching material, compatible with the coating material and inert in concrete, shall be supplied with each shipment.
7.For projects where epoxy-coated steel reinforcing bars are used in the top mat of bridge decks only, the maximum amount of damage to the coating shall not exceed 0.25 percent of the surface area of each bar.
8.The thickness of epoxy coating shall be 10 mils plus or minus 2 mils.
9.Samples, when required, shall be shipped to the Washington State Department of Transportation, Materials Laboratory, 1655 South 2nd Avenue, Tumwater, WA 98504.
9-07.4 Plain Steel Bars
Where plain steel bars are specified, they shall conform to the chemical and physical properties of AASHTO M 31, Grade 60, unless specifically noted otherwise. Plain steel bars are indicated in the Plans and Specifications by fractions of an inch; for example, ⅜ inch Ø, ½ inch Ø, ⅝ inch Ø, etc.
9-07.5 Dowel Bars (for Cement Concrete Pavement)
9-07.5(1) Dowel Bars for Cement Concrete Pavement Rehabilitation
Dowel bars for Cement Concrete Pavement Rehabilitation shall be 1½ inch outside diameter plain round steel bars or tubular bars 18 inches in length and meet the requirements of one of the following: dowel bar types:
1.Epoxy-coated dowel bars shall be round plain steel bars of the dimensions shown in the Standard Plans . They shall conform to AASHTO M 31, Grade 60 or ASTM A615, Grade 60 and shall be coated in accordance with ASTM A1078 Type 2 coating, except that the bars may be cut to length after being coated. Cut ends shall be coated in accordance with ASTM A1078 with a patching material that is compatible with the coating, inert in concrete and recommended by the coating manufacturer. The thickness of the epoxy coating shall be 10 mils plus or minus 2 mils. The Contractor shall furnish a written certification that properly identifies the coating material, the number of each batch of coating material used, quantity represented, date of manufacture, name and address of manufacturer, and a statement that the supplied coating material meets the requirements of ASTM A1078 Type 2 coating. Patching material, compatible with the coating material and inert in concrete and recommended by the manufacturer shall be supplied with each shipment for field repairs by the Contractor.
2.ASTM A513 steel tubes made from Grade 60 Carbon Steel Tube with a 1.625 inch outside diameter and a 0.120-inch wall thickness. Both the inside and outside of the tube shall be zinc coated with G40 galvanizing in accordance with ASTM A653. Following zinc coating the tubes shall be coated in accordance with Section 9-07.5(1) item 1. The ends of the tube shall be capped to prevent intrusion of concrete or other materials. Page 9-66 M 41-10
9-07 Reinforcing Steel9-07.5(2) Corrosion Resistant Dowel Bars (for Cement Concrete Pavement
and Cement Concrete Pavement Rehabilitation) Corrosion resistant dowel bars shall be 1½ inch outside diameter plain round steel bars or tubular bars 18 inches in length and meet the requirements of one of the following:
1.Stainless Steel-Clad dowel bars shall have a minimum 0.06 inches clad to a plain steel inner bar meeting the chemical and physical properties of AASHTO M31, Grade 60, or AASHTO M255, Grade 60. Stainless Steel Clad shall meet the chemical properties of ASTM A276, Type 316L.
2.Stainless Steel Tube dowel bars shall have a minimum 0.06-inch-thick tube press- fitted onto a plain steel inner bar meeting the chemical and physical properties of AASHTO M 31, Grade 60, or AASHTO M255, Grade 60. A lubricant/adhesive shall be used between the tube and the plain steel bar to fill any voids. Stainless Steel Tube material shall meet the chemical properties of ASTM A276, Type 316L.
3.Stainless Steel Solid dowel bars shall be ASTM A276, Type 316L.
4.Corrosion-resistant, low-carbon, chromium plain steel bars for concrete reinforcement meeting all the requirements of ASTM A1035 Alloy Type CS Grade 100 or Alloy Type CS Grade 120.
5.Zinc Clad dowel bars shall be 1½ inch solid bars meeting the chemical and physical properties of AASHTO M 31, Grade 60 or AASHTO M 255, Grade 60 or ASTM A513 steel tubes made from Grade 60 carbon steel tube with a 1.625 inch outside diameter by 0.120-inch wall thickness. The bars shall have a minimum 0.035 inches A710 Zinc alloy clad to the plain steel inner bar or tube. A710 Zinc shall be composed of zinc: 99.5 percent, by weight, minimum; copper: 0.1 – 0.25 percent, by weight; and iron: 0.0020 percent, by weight, maximum. Each end of tubular bars shall be plugged using a snug-fitting insert to prohibit any intrusion of concrete or other materials.
6.Multicoated fusion bonded epoxy bars shall consist of an ASTM A615 bar with alternating layers of ASTM A934 coating and an abrasion resistant overcoat (ARO). The ASTM A934 coating shall form the base and there shall be two layers of each coating material. The minimum thickness of the combined layers of the ASTM A934 coating and ARO coating shall be 20 mils. The ARO shall meet the following requirements: Test Method Specification Gouge Resistance NACE TM0215, 30 kg wt., LS-1 bit @ 25°C < 0.22 mm Gouge Resistance NACE TM0215, 50 kg wt., LS-1 bit @ 25°C < 0.44 mm
7.ASTM A513 steel tubes made from Grade 60 Carbon Steel Tube with a 1.625 inch outside diameter and a 0.120-inch wall thickness. Both the inside and outside of the tube shall be zinc coated with G90 galvanizing in accordance with ASTM A653. Following zinc coating the tubes shall be coated in accordance with Section 9-07.5(1) item 1. The ends of the tube shall be capped to prevent intrusion of concrete or other materials. The surface of the finished cut-to-length corrosion-resistant, low-carbon, chromium plain steel bars for concrete reinforcement meeting all the requirements of ASTM A1035 dowels shall be provided with a hot-rolled, as-rolled finish, including mill scale. The surface of all other finished cut-to-length dowels shall be provided with a smooth “ground” or “cold drawn” finish. Stainless Steel Clad and Stainless Steel Tube Dowel bar ends shall be sealed with a patching material (primer and finish coat) used for patching epoxy-coated reinforcing steel as required in Section 9-07.3 , item 6. M 41-10 Page 9-67 Reinforcing Steel 9-079-07.6 Tie Bars (for Cement Concrete Pavement) Tie bars shall conform to the requirements of the Standard Specifications for Deformed Billet Steel Bars for Concrete Reinforcement, AASHTO M 31, Grade 60 and shall be coated in accordance with ASTM A775 or corrosion-resistant, uncoated, low-carbon, chromium deformed steel bars for concrete reinforcement meeting all the requirements of ASTM A1035. The form of the deformed bar shall be subject to approval by the Engineer. Tie bars shall be free from dirt, grease, or other defects affecting the strength or bond with the concrete.
9-07.7 Welded Wire Reinforcement
Welded wire for concrete reinforcement shall meet the requirements of ASTM A1064, Carbon-Steel Wire and Welded Wire Reinforcement, Plain and Deformed, for Concrete. Welded wire reinforcement manufacturers shall participate in the NTPEP Audit Program for Reinforcing Steel (rebar) Manufacturers and shall be listed on the NTPEP audit program website displaying that they are NTPEP compliant.
9-07.8 Deformed Wire
Deformed wire shall conform to the requirements of AASHTO M 336, Deformed Steel Wire for Concrete Reinforcement. Deformed wire is noted in the Plans and Specifications by the letter D, followed by a number indicating the cross sectional area of the wire; for example, D2, D5, D20, etc.
9-07.9 Cold Drawn Wire
Cold drawn wire shall conform to the requirements of AASHTO M336, Cold Drawn Steel Wire for Concrete Reinforcement. Cold drawn wire is noted in the Plans and Specifications by the letter W followed by a number indicating the cross-sectional area of the wire; for example, W2, W5, W20, etc.
9-07.10 Prestressing Reinforcement Strand
Prestressing reinforcement shall be ½-inch diameter for precast-prestressed concrete piles and ½- or 0.6-inch diameter for pretensioned concrete girders, post-tensioned segmental precast concrete girders, or cast-in-place prestressed concrete. Prestressing reinforcement shall be mill bright high tensile strength seven wire low relaxation strand conforming to the requirements of AASHTO M 203 (ASTM A416), Grade 270. Each reel of prestressing reinforcement shall be accompanied by a Manufacturer’s Certificate of Compliance, a mill certificate, and a test report. The mill certificate and test report shall include the yield and ultimate strengths, elongation at rupture, modulus of elasticity, and the stress strain curve for the actual prestress reinforcing intended for use. All values certified shall be based on test values and actual sectional areas of the material being certified. For every five reels furnished, one sample, not less than 5½ feet long, shall be sent to the Engineer for testing. Samples of the furnished reels with Manufacturer’s Certificate of Compliance, a mill certificate, and test report may be shipped directly by the manufacturer to the Engineer. An independent inspector, approved by the Contracting Agency, shall be present during sampling and shall provide a written certification to the Engineer. Page 9-68 M 41-10
9-07 Reinforcing Steel9-07.11 Prestressing Reinforcement Bar
High-strength steel bars shall conform to AASHTO M 275, Type II. Nuts shall conform to either ASTM A29 Grade C1045, or ASTM A536 Grade 100-70- 03, and shall be capable of developing the larger of either 100 percent of the minimum ultimate tensile strength (MUTS), or 95 percent of the actual ultimate tensile strength (AUTS), of the bar. The anchor nuts shall conform to the specified strength requirement while permitting a maximum 5-degree misalignment between the nut and the bearing plate. A minimum of three tests, each from a different heat, are required. Couplers, if required, shall be AASHTO M 169 Grade 1144, or equivalent steel, developing the larger of either 100 percent of the MUTS, or 95 percent of the AUTS, of the bar. The test shall be performed with the coupler having a one-inch unengaged segment between the two coupled bars. A minimum of three tests, each from a different heat, are required. For unbonded bars under dynamic loading, the connections shall withstand at least 500,000 cycles from 60 percent to 66 percent MUTS followed by at least 50 cycles between 40 percent MUTS and 80 percent MUTS. A minimum of three tests, each from a different heat, are required. The Contractor shall supply a Manufacturer’s Certificate of Compliance in accordance with Section 1-06.3 for each bar. The Contractor shall supply a Manufacturer’s Certificate of Compliance in accordance with Section 1-06.3 for all nuts and couplers, confirming compliance with the specified strength requirement. For each heat of steel for high-strength steel bar, the Contractor shall submit two samples, each not less than 5½ feet long, to the Engineer for testing.
Source: Washington Standard Specifications for Road, Bridge, and Municipal Construction, 2024 Edition. Pages 973–978 of 1,151.