for Highway Construction Page 330 of 71 5 SECTION 503 – METAL REINFORCEMENT
503.01 Description.
Provide and install reinforcing steel . The metal reinforcement, Schedule no. 1 pay item includes metal reinforcements placed in subst ructures. The metal reinforcement, Schedule no. 2 pay item includes metal reinforcement placed in superstructures. The Department will show the schedules in the plans for the structures involved.
503.02 Materials.
Provide materials as specified in: Reinforcing Steel ..................................................................................................................... 708.02 Epoxy -Coated Metal Reinforcement ........................................................................................ 708.02 Dowel Bars .............................................................................................................................. 708.03 Tie Bars ................................................................................................................................... 708.04 Splices ..................................................................................................................................... 708.32 Order additional bars to account for the field sampling. Do not cut and splice bars to obtain samples. Com plete fabricated bars are to be sampled and replaced. Order additional mechanical splices to account for field sampling. Provide reinfor cing steel spirals with additional length to accommodate sampling. Do not cut and splice material to obtain samples. Replace bar from failing heat numbers at no additional cost to the Department.
503.03 Construction Requirements.
A.Bar List and Bending Schedule . The plans will show the bar list and bending sc hedule to arrive at an estimate of quantities . Verify the quantity , size, and shape of the bar reinforcement against the structure drawings and make necessary corrections before ordering. The Department will not adjust the contract unit price because of errors in the bar list and bending schedule.
B.Protection of Material . Protect steel reinforcement from damage. When placed, ensure the steel reinforcement does not have dirt, detrimental scale, paint , oil, or other foreign substance. Do not store epoxy -coated reinforcing steel outdoors for more than 2 months. When stored outdoors, cover the bars to protect them against the elements and against condensation forming on the bars.
C.Bending. Field bend reinforcing bars only when the bars conflict with prestressing ducts , are within anchorage recesses, or as specified. Do not field bend:
1.Bar sizes larger than No. 7. for Highway Construction Page 331 of 715 2. When the application of heat is required and the ambient temperature is lower than 50°F and wind velocity at the bending site exceeds 15 mph.
3.By means of hammer blows or other impact loading. Do the following when field bending steel reinforcing bars:
1.Make the bend gradually.
2.Apply heat in bending bars sizes No. 6 and No. 7 or in bending bar sizes No. 5 and smaller when those bars have been previously bent. Previously unbent bars of sizes No. 5 and smaller may be bent without heating.
3.Use a bending tool equipped with a bend inside diameter / bar diameter ratio of 8.
4.Limit bends to a maximum of 90 degrees.
5.Straighten by moving a hickey bar, if used, progressively around the bend. Do the following in applying heat for field bending steel reinforcing bars:
1.Use only rosebud type torch tips, designed to give a diffused flame.
2.Insulate conc rete within 6 inches of the heated bar area.
3.Ensure by means of temperature indicating crayons or other suitable means the steel temper ature at the end of a heating operation will be as follows:
a.1,200°F to 1,250°F for bar size No. 4
b.1,350° F to 1,400°F for bar sizes No. 5 and No. 6
c.1,400°F to 1,445°F for bar size No. 7
4.Heat the entire length of the bend plus a 2 inches additional length on each side of the bend.
5.Maintain the steel temperature within the required range shown above during the entire bending process.
6.Bend the bar immediately after the required temperature has been reached.
7.Never cool bars artificially with water, forced air, or by placing them on the ground or a concrete floor or other means.
8.Transport or install hot, bent bars after they have reached the ambient temperature. Submit a field bending plan for approval including a d escription of the proposed methods, tools, materials, and handling of the field bent reinforcement before bending bars in the field.
D.Placing and Fastening. Firmly hold reinforcing steel in the position specified while placing concrete. Maintain reinforcement position by means of stays, blocks , ties, hangers, or other approved supports . Do not space the supports for metal reinforcement more than 4 feet apart transversally or longitudinally. If concrete blocks are used, embed the appropriate tie wires or coated tie wires during their forming stage and tie each block to the reinforcing bar it supports to hold the block in place. Ensure concrete blocks have a pproximately the same strength quality as the concrete placed around them. The Department requires plastic -coated tie wire and plastic -coate d metal bar supports whenever they will be in direct contact with epoxy -coated reinforcing. Do not use pebbles, pieces of broken stone, broken concrete, metal pipe, or wooden blocks. Tie down top layers or mats of metal for Highway Construction Page 332 of 715 reinforcement in bridge deck s to stirrups or shear studs. Locate tie downs so there is at l east 1 tie down per 16 square feet of deck surface. Provide tie downs strong enough to prevent upward movement of reinforcement. Do not deviate more than plus or minus 0.25 inch in the vertical direction from the position specified for concrete deck reinforcing steel. Do not place concrete until the Engineer has inspected the reinforcement . Repair damage to epoxy coating of reinforcing steel occurring during installation before placing. Remove rust and contaminants from the steel surface and adjacent coating, by wire brushing, immediately before applying patching mat erial. Use a patching material certified to meet ASTM A775 and apply it in accorda nce with the manufacturer’s written instructions. Tie reinforcing bars at intersections, unless spacing is less than 1 foot in each direction, then tie the alternate intersec tions. Where bundled bars are shown on plans, tightly tie bundles at intervals not exceeding 3 feet with No. 16 or larger black or plastic -coated steel wire. Do not weld reinforcing steel unless shown on plans or appr oval has been obtained. Weld in accordance with AWS D1.4 Structural Welding Code - Reinforcing Steel. The Contractor may weld reinforcing steel assemblies if approved for precast items instead of tying, as follows:
1.Weld at locations shown on the approved shop drawings .
2.Do not weld at the casting bed when prestress reinforcement is on the bed.
3.The Contractor may tack weld design bars as specified to extra N o. 4 bars for positioning. Do not exceed 1 inch weld length tack welds and locate only at the very ends of design bars. Show the extra bars on the shop drawings and identify as bars whose only function is to position the design bars. Extra bars and design bars have the same concrete cove r requirement. Locate extra bars to not interfere with prestress reinforcement or other design details. The Contractor may weld positioning bars to each other.
4.Epoxy coat the positioning bars if epoxy -coated bars ar e specified. Clean welds and weld- damaged coating with wire brush and coat with a patching compound recommended by the epoxy supplier.
E.Splices. Provide reinforcement in the full length specified except for column spirals. Do not splice bars, except where specified and in the column spirals. Rigidly clamp or wire bars at splices in a manner approved. Do not field splice column spirals in the lower ¼ or the upper ¼ of the spiral. At other locations in the column, the Contractor may provide welded splices in column spirals that meet AWS D1.4 or provide approved mechanical splices for field splices in column spir als. Form mechanical splices for epoxy and non- epoxy -coated bars with an approved system using mechanical couplers that comply with this section at locations where mechanical splices are required. Do not weld splices. Epoxy coat or protect exposed spli ce components used for the epoxy -coated bars from corrosion by other approved means. Submit the following information for each shipment of splice material before splicing:
1.The type of series identif ication and heat treatment lot number for threaded- sleeve splices.
2.The grade and size of the bar to be spliced. for Highway Construction Page 333 of 71 5 3. A manufacturer’s catalog with complete data on material and procedures.
4.A written statement from the Contractor the system and materials will be used in ac cordance with the manufacturer’s instructions and requirements of this section. Make one tension test specimen splice to represent each lot of bars spliced at the project site and submit for testing 15 calendar days before installation. A lot consists of every 50 epoxy -coated or every 50 non- epoxy - coated bars spliced at the project site of one size. Tension test each specimen to destruction or to the specified ultimate strength, whichever is less. Ensu re mechanical splices meet the following criteria:
1.Develops at least 125 percent of the yield tensile strength specified for the unspliced bar. The ultimate tensile strength of the sleeve exceeds that of the other parts of the completed splice.
2.Slippag e for AASHTO M 31 Grade 60 bars within a splice sleeve is limited to a maximum of 0.045 inch. Measure the slippage between gauge points clear of the splice sleeve. Take measurements at initial load of 3,000 psi and again after loading to 90 percent of the minimum specified yield strength for the unspliced bar and then relaxed to 3, 000 psi.
503.04 Method of Measurement.
The Engineer will measure acceptably completed work by the pound, based on the theoretical pound unit weight. The Engineer will measure epoxy -coated metal reinforcement by the pound of reinforcing steel before coating, based on the theoretical pound unit weight.
503.05 Basis of Payment .
The Department will pay for accepted quantities at the contract unit prices as follows: Pay Item Pay Unit Metal Reinforcement .............................................................................. lb Metal Reinforcement , Schedule No. ____ .............................................. lb Epoxy -Coated Metal Reinforcement ....................................................... lb No allowance will be made for clips, wire , or other material used for fastening reinforcement in place. No allowance will be mad e for plastic -coated wires, supports or other material used for fastening epoxy - coated reinforcement . The Department will include the weight of the splice bars for which payment is made, if the splice bars are specified or as directed. The Department will not pay for bars installed for the Contractor’s convenience. The Department will pay for Schedule 2 Metal Reinforcement using plan quantities as specified in 109.01. The Department will not provide separate payment for the cost of providing and installing mechanical splices or for testing where required. These costs are incidental and included in the contract unit prices for metal reinforcement . for Highway Construction Page 334 of 71 5 SECTION 504 – STRUCTURAL METALS
504.01 Description.
A.General. Provide, fabricate, erect, and paint structural met als.
B.Fabricator Certification . Fabricators of structural components for vehicular bridges, other than unspliced rolled beam bridges, are to be certified under the AISC Quality Certification Program, intermediate or advanced steel bridge categories. Fabricators of structural components for unspliced, rolled beam vehicular bridges and steel pedestrian bridges are to be certified under the AISC Quality Certification Program, simple steel bridge structures category. Fabricators of fracture critical members are to hold a fracture critical endorsement in addition to the above requirements. This does not apply to incidental sub-assemblies (e.g., drainage components, expansion joints , handrails, lighting supports ).
C.Notice of Rolling and Fabrication. Give a 90 -day notice before beginning work at the mill or shop so the Department can prepare for inspection. Do not manufacture material or perform work in the shop before the Engineer has been notified.
D.Inspection. The Department will inspect structural steel at the fabrication site. Submit electronic copies of mill orders, certified mill test reports and shipping statements. On mill test reports, show the chemical analysis and physical test results for each heat of steel used in the work. Submit certificates of compliance instead of mill test reports for material that normally is not supplied with mill test reports (e.g., fills, minor gusset plates, quantities are small and the material is taken from s tock). Submit certified mill test reports for steels with specified impact values that include, in addition to other test results, the results of Charpy V -notch impact tests. When fine grain practice is specified, include confirmation the material was so produced. Submit copies of mill orders at the time orders are placed with the manufacturer. Submit certified mill test reports and certificates of compliance before starting material fabrication covered by these reports. Submit the certificate of compliance signed by the manufacturer certifying the material is in compliance with the specifications to which it has been manufactured. Make available to the Engineer material to be used so each piec e can be examined. Provide the Engineer with safe access to the fabrication site where the material is stored or where work on the material is being performed.
E.Quality Control Inspection . Be responsible for quality control inspection and testing. Perform inspection and testing at least to the extent specified and in accordance with the ANSI/ AASHTO/ AWS D1.5 Bridge Welding Code, Inspection. Include nondestructive testing in addition to visual inspection, testing to base metal, production welds, weld repairs , procedure qualification test weldments and welder, wel ding operator, and tacker qualification test weldm ents. This work is incidental and the costs are to be included in the contract unit prices for the structural steel . Provide facilities to inspect material and work.
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 366–369 of 768.