1 Scope
NOTE This specification covers the materials, fabrication, delivery, and installation of steel reinforcing bars and welded wire reinforcement for cast-in-place reinforced concrete construction. (1.1)
NOTE Reinforcing steel is not a commodity item installed by rote. (1.2)
NOTE Its structural function depends entirely on its grade, coating condition, precise placement, adequate cover, and properly developed splices. (1.3)
NOTE A bar placed one inch low in a slab, a lap splice too short by six bar diameters, or a tie displaced during concrete vibration can each compromise the structural integrity of the element. (1.4)
NOTE Reinforcing steel work under this specification includes: deformed reinforcing bars (straight, bent, and headed), plain bars used as spirals or column ties where permitted, welded wire reinforcement (WWR) in rolls and sheets, mechanical splicing systems (couplers and headed bar terminations), bar supports and chairs, and field welding of reinforcement where permitted by the Contract Documents. (1.5)
1.6 All reinforcement shall conform to ACI CODE-318-19(22), Building Code Requirements for Structural Concrete and Commentary.
1.7 Reinforcement shall be installed in strict accordance with the Contract Drawings, the Shop Drawings reviewed under this specification, and ACI SPEC-301-16, Specifications for Structural Concrete.
1.8 Where these documents conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
NOTE This specification shall be read in conjunction with
Cast In Place Concrete for requirements governing the concrete itself.
(1.9) 2 Referenced Standards
2.1 Materials, fabrication, and installation shall comply with the latest adopted edition of the following standards and codes.
| Standard |
Title |
| ACI CODE-318-19(22) |
Building Code Requirements for Structural Concrete and Commentary |
| ACI SPEC-301-16 |
Specifications for Structural Concrete |
| ACI 117-10 |
Specification for Tolerances for Concrete Construction and Materials |
| ASTM A615/A615M |
Standard Specification for Deformed and Plain Carbon-Steel Bars for Concrete Reinforcement |
| ASTM A706/A706M |
Standard Specification for Deformed and Plain Low-Alloy Steel Bars for Concrete Reinforcement |
| ASTM A1035/A1035M |
Standard Specification for Deformed and Plain, Low-Carbon, Chromium, Steel Bars for Concrete Reinforcement |
| ASTM A775/A775M |
Standard Specification for Epoxy-Coated Steel Reinforcing Bars |
| ASTM A934/A934M |
Standard Specification for Epoxy-Coated Prefabricated Steel Reinforcing Bars |
| ASTM A767/A767M |
Standard Specification for Zinc-Coated (Galvanized) Steel Bars for Concrete Reinforcement |
| ASTM A1064/A1064M |
Standard Specification for Carbon-Steel Wire and Welded Wire Reinforcement, Plain and Deformed, for Concrete |
| AWS D1.4/D1.4M |
Structural Welding Code — Reinforcing Steel |
| ASTM A370 |
Standard Test Methods and Definitions for Mechanical Testing of Steel Products |
| CRSI MSP |
CRSI Manual of Standard Practice (current edition) |
| CRSI RB4.1 |
Supports for Reinforcement Used in Concrete |
| IBC |
International Building Code (locally adopted edition) |
2.2 Materials, fabrication, and installation shall comply with the latest adopted edition of the referenced standards and codes.
2.3 Where a more recent edition of a referenced standard has been adopted by the Authority Having Jurisdiction since the date of these Contract Documents, the Contractor shall notify the Engineer of Record before proceeding.
3 Submittals
3.1 Shop Drawings and Bar Lists
3.1.1 Contractor shall submit shop drawings and bar lists for review by the Engineer of Record before any reinforcement is fabricated or delivered to the project site.
● Yes — no reinforcement shall be fabricated or ordered until shop drawings are reviewed
○ No — proceed from Contract Drawings with Engineer approval
3.1.2 Contractor shall submit shop drawings and bar lists for review by the Engineer of Record before any reinforcement is fabricated or delivered to the project site.
3.1.3 Shop drawings shall be prepared by a qualified detailer in accordance with the CRSI Manual of Standard Practice and shall show, for every concrete element, bar sizes, grades, coatings, lengths, bends, hook geometry, placement dimensions, bar spacing, concrete cover to each bar face, splice locations and lengths, mechanical coupler types and locations, lap zones, and bar support locations and types.
3.1.4 Bar lists shall be keyed to the shop drawing mark system and shall state, for each bar mark, bar designation, grade, coating, quantity, length, bending details with critical dimensions flagged, and unit and total weight.
3.1.5 Bar lists shall be complete enough that no additional information is required from the Contract Drawings during fabrication.
3.2 Mill Certifications
3.2.1 Certified mill test reports (CMTRs) shall be submitted for every heat of steel used on the project.
● Yes — CMTR for every heat incorporated into the work
○ Yes — CMTR for primary structural elements; standard certification for slabs-on-grade only
3.2.2 Certified mill test reports (CMTRs) shall be submitted for every heat of steel used on the project.
3.2.3 CMTRs shall show heat number, bar designation and grade, carbon equivalent (CE) for bars designated for welding, yield strength, tensile strength, elongation, and bend test results.
3.2.4 CMTRs shall be submitted before the material they represent is incorporated into the work.
3.2.5 For ASTM A706 bars designated for field welding, the carbon equivalent shall not exceed the maximum specified in ASTM A706.
3.2.6 For ASTM A615 bars proposed for welding, chemical analysis shall be submitted and reviewed by the Engineer before welding commences, with weldability assessment governed by ACI 318-19 Section 26.6.2 and AWS D1.4.
3.3 Product Data for Mechanical Splicing Systems
3.3.1 Where mechanical splices (couplers, headed bars, or end-bearing splices) are used, Contractor shall submit product data for the splicing system.
3.3.2 Where mechanical splices (couplers, headed bars, or end-bearing splices) are used, Contractor shall submit product data including coupler designation, bar sizes and grades compatible, performance classification per ACI 318-19 Section 26.6.3 (Type 1 or Type 2), test reports confirming required performance, and manufacturer's installation and torque requirements.
3.3.3 Mechanical coupler data shall be submitted before installation of the first coupler.
3.4 Special Inspection Program
3.4.1 Where special inspection of reinforcement is required by the locally adopted IBC and the project's Statement of Special Inspections, the Contractor shall coordinate the inspection program with the Special Inspector.
3.4.2 Where special inspection of reinforcement is required by the locally adopted IBC and the project's Statement of Special Inspections, the Contractor shall coordinate the inspection program with the Special Inspector.
3.4.3 Special inspection submittals shall be made in accordance with the Statement of Special Inspections, not this specification section alone.
3.5 Closeout Submittals
3.5.1 At project closeout, Contractor shall provide the following:
- As-built markup drawings indicating all field changes to reinforcement placement, splices, and cover that deviated from the reviewed shop drawings and were accepted by the Engineer of Record
☐ As-built markup drawings of field changes to reinforcement placement, splices, and cover
3.5.2 At project closeout, Contractor shall provide as-built markup drawings indicating all field changes to reinforcement placement, splices, and cover that deviated from the reviewed shop drawings and were accepted by the Engineer of Record.
3.5.3 Deviations not documented and accepted shall be treated as nonconformances.
4 Quality Assurance
4.1 Fabricator Qualifications
4.1.1 Reinforcing steel fabrication shall be performed by a fabricator regularly engaged in the production of reinforced concrete steel for structural construction.
4.1.2 The fabricator shall maintain current CRSI Chapter Certification or equivalent certification from an approved certification program.
4.1.3 The fabricator shall have in-house bending and cutting equipment capable of producing the required bar sizes without overstress or cracking at bend points.
4.2 Installer Qualifications
4.2.1 Reinforcement shall be placed by a contractor experienced in reinforced concrete construction and capable of maintaining the tolerances specified in ACI 117.
4.2.2 Workers who make field welds on reinforcing steel shall be qualified welding operators tested and certified in accordance with AWS D1.4 for the processes and positions used on this project.
4.2.3 Qualification records shall be available to the Special Inspector on request.
4.3 Special Inspection
4.3.1 Special inspection of reinforcing steel shall be performed in accordance with IBC Chapter 17, the locally adopted building code, and the project's Statement of Special Inspections.
● Yes — per IBC Chapter 17 and Statement of Special Inspections
○ No — not required for this project (Engineer of Record to confirm)
4.3.2 Special inspection of reinforcing steel shall be performed in accordance with IBC Chapter 17, the locally adopted building code, and the project's Statement of Special Inspections.
4.3.3 The type and frequency of special inspection shall be as indicated in the Statement of Special Inspections, which takes precedence over any conflicts with this specification.
4.3.4 Special inspection shall include, at minimum, verification of bar grade and size against shop drawings, inspection of bar placement, cover, spacing, and lap lengths prior to concrete placement, and observation of mechanical splice installation.
4.4 Code Compliance
4.4.1 All reinforcing steel work shall be designed, detailed, and placed in accordance with ACI CODE-318-19(22).
4.4.2 Where the Engineer of Record has specified a locally adopted edition of ACI 318 that differs from ACI 318-19, the requirements of the locally adopted edition shall govern for code compliance.
5 Reinforcing Bar Materials
5.1.1 ASTM A615 Carbon-Steel Bars
NOTE ASTM A615 deformed bars are the most widely used reinforcing bars in the United States and are the default specification for most cast-in-place structural concrete work. (5.1.1.1)
NOTE ASTM A615 is available in Grade 40, Grade 60, Grade 80, and Grade 100, with yield strengths of 40,000 psi, 60,000 psi, 80,000 psi, and 100,000 psi respectively. (5.1.1.2)
Grade 60 (ASTM A615)
Grade 80 (ASTM A615)
Grade 60, weldable (ASTM A706)
Grade 80, weldable (ASTM A706)
Grade 100 (ASTM A1035 or ASTM A615)
Per drawings
5.1.1.3 Grade 60 is the predominant grade in current commercial construction and is the default for most elements unless the Contract Drawings specify otherwise.
5.1.1.4 Where the Contract Drawings require Grade 80 or Grade 100 bars, those grades shall be furnished within the element and load-combination limits ACI 318-19 places on higher-strength grades.
5.1.1.5 Field welding of ASTM A615 bars shall require chemical analysis of each heat before welding to establish a preheat requirement per AWS D1.4.
NOTE Grade 80 and Grade 100 bars permit reduced cross-sectional steel area for a given force demand and are used where congestion is a concern or where high-performance concrete design is employed. (5.1.1.6)
NOTE ASTM A615 bars have no controlled chemistry requirement and are therefore not routinely weldable. (5.1.1.7)
5.1.2 ASTM A706 Low-Alloy Weldable Bars
NOTE ASTM A706 deformed bars are specified where field welding of reinforcement is anticipated, or where enhanced ductility and predictable yield-to-tensile ratios are required for seismic design. (5.1.2.1)
NOTE ASTM A706 limits carbon equivalent and alloy chemistry so that bars are weldable in accordance with AWS D1.4 without chemical analysis of individual heats. (5.1.2.2)
NOTE ASTM A706 is available in Grade 60 and Grade 80. (5.1.2.3)
● Yes — for all field-welded reinforcement and seismic force-resisting systems
○ Yes — for seismic force-resisting systems only
○ Yes — for field-welded bars only
○ No — ASTM A615 permitted throughout
5.1.2.4 For seismic force-resisting systems in Seismic Design Categories D, E, and F, longitudinal bars in special moment frames and special structural walls shall be ASTM A706 per ACI 318-19 Chapter 18 unless the Engineer of Record has specifically approved ASTM A615 based on project-specific testing.
5.1.2.5 Where the Contract Drawings designate seismic application requirements, ASTM A706 bars shall be used unless the Contract Drawings explicitly permit ASTM A615.
5.1.3 ASTM A1035 High-Strength Bars
NOTE ASTM A1035 deformed bars (Grade 100 and Grade 120) are low-carbon, chromium-alloy bars with significantly higher strength and corrosion resistance than ASTM A615. (5.1.3.1)
NOTE They are used in congested sections, transfer elements, high-rise columns, and marine or aggressive exposure environments where their inherent corrosion resistance eliminates or reduces the need for coating. (5.1.3.2)
NOTE ACI PRC-439.6-19 provides guidance on design using ASTM A1035 bars. (5.1.3.3)
5.1.3.4 The use of ASTM A1035 bars shall be limited to applications specifically designated on the Contract Drawings.
5.1.3.5 Grade 100 and Grade 120 bars shall be used only within the application limitations ACI 318-19 places on ductility-sensitive seismic elements.
NOTE ASTM A1035 bars are not routinely weldable; their high strength and unique chemistry require special consideration under AWS D1.4. (5.1.3.6)
5.2 Bar Sizes
5.2.1 Reinforcing bars shall be furnished in standard ASTM bar designations from No. 3 through No. 18, as indicated on the Contract Drawings and shop drawings.
NOTE Bar designation numbers correspond to the nominal diameter in eighths of an inch: No. 3 = 3/8 in., No. 4 = 1/2 in., No. 5 = 5/8 in., and so on. (5.2.2)
No. 8 and smaller
No. 9 through No. 11
No. 14 or No. 18 (requires mechanical splices — no lap splices)
Per drawings (deferred by default)
5.2.3 Reinforcing bars shall be furnished in standard ASTM bar designations from No. 3 through No. 18, as indicated on the Contract Drawings and shop drawings.
5.2.4 Bar sizes larger than No. 11 (1-3/8 in. nominal diameter) shall observe lap splicing restrictions, and ACI 318-19 prohibits lap splices for No. 14 and No. 18 bars except for specific conditions.
5.2.5 Substitute bar sizes may be used only with written approval of the Engineer of Record and shall provide equivalent or greater cross-sectional area and equivalent or greater development capacity.
5.3 Coated Reinforcing Bars
5.3.1 Epoxy-Coated Bars
NOTE Epoxy-coated reinforcing bars are specified for elements in direct contact with de-icing salts (parking garage decks, bridge abutments, exterior slabs), for submerged or splash-zone concrete, and for other high-chloride exposure environments. (5.3.1.1)
NOTE The epoxy coating reduces chloride ion penetration to the bar surface and significantly extends time-to-corrosion in aggressive exposures. (5.3.1.2)
● Not required — uncoated bars throughout
○ Required — ASTM A775 (coated straight, bent after coating)
○ Required — ASTM A934 (bent first, coated after bending)
○ Required — zone and element designations per Contract Drawings
5.3.1.3 Epoxy-coated reinforcing bars shall conform to ASTM A775/A775M (bars coated in the straight condition and bent after coating) or ASTM A934/A934M (bars coated after bending), as required by the Contract Drawings.
5.3.1.4 Where bars must be bent in the field, ASTM A775 bars shall be used.
5.3.1.5 Where bars are to be bent at the fabrication shop before coating, ASTM A934 bars shall be used.
NOTE Cover requirements for epoxy-coated bars are specified in ACI 318-19 Table 20.6.1 and in the Concrete Cover section of this specification; epoxy coating is not a substitute for adequate concrete cover. (5.3.1.6)
5.3.1.7 Epoxy-coated bars shall be handled carefully throughout delivery, storage, bending, placing, and concrete placement to avoid coating damage.
5.3.1.8 Bars shall not be dragged across surfaces or against each other.
5.3.1.9 All coating damage occurring after fabrication — cuts, abrasions, and voids — shall be repaired with an approved patching compound compatible with the coating system before concrete is placed.
5.3.1.10 Any unrepaired damage area exceeding the ASTM A775 or ASTM A934 allowable shall be cause for rejection.
5.3.2 Galvanized Bars
5.3.2.1 Galvanized bars are used where long-term corrosion resistance is required and epoxy coating is not preferred — for example, where bars must remain visually inspectable throughout their life, or where the project owner prefers galvanizing for compatibility with other galvanized components.
● Not required
○ Required — ASTM A767 Class I coating
○ Required — ASTM A767 Class II coating
○ Required — zones and elements per Contract Drawings
5.3.2.2 Zinc-coated (galvanized) reinforcing bars shall conform to ASTM A767/A767M.
5.3.2.3 Galvanized bars shall not be used in conjunction with aluminum embedments without an isolation barrier.
NOTE Contact between zinc and aluminum in a wet concrete environment creates a galvanic couple that accelerates corrosion of the aluminum. (5.3.2.4)
5.3.3 Stainless Steel Bars
5.3.3.1 Stainless steel reinforcing bars (ASTM A955/A955M) may be specified for extremely aggressive environments — marine immersion zones, structures exposed to severe chemical attack, and bridges in high-chloride regions — where neither epoxy coating nor galvanizing provides sufficient service life.
NOTE Stainless steel bars are significantly more expensive than coated carbon-steel bars. (5.3.3.2)
● Not required
○ Required — ASTM A955 Type 304 stainless
○ Required — ASTM A955 Type 316 stainless (highest chloride resistance)
○ Required — zones and elements per Contract Drawings
5.3.3.3 The use of stainless steel reinforcing bars shall be limited to elements and zones specifically designated on the Contract Drawings.
5.4 Welded Wire Reinforcement
NOTE Welded wire reinforcement (WWR) is furnished as flat sheets or rolls. (5.4.1)
5.4.2 Sheets are preferred for formed slabs where the mat must be placed at a specific elevation without continuous reshaping; rolls are common for slabs-on-grade and for elements where continuous longitudinal feed is practical.
● Flat sheets
○ Rolls
○ Not used on this project
Per drawings — structural drawings
○ Plain wire (W-series designation)
● Deformed wire (D-series designation)
Per drawings
5.4.3 Welded wire reinforcement (WWR) shall conform to ASTM A1064/A1064M, which consolidates plain and deformed wire and welded wire reinforcement into a single standard.
5.4.4 Where legacy Contract Documents reference the withdrawn ASTM A185 (plain) or ASTM A497 (deformed) specifications, the Contractor shall supply material meeting ASTM A1064, which is the current specification.
5.4.5 WWR spacing and wire sizes shall be as indicated on the Contract Drawings.
5.5 Identification and Marking
5.5.1 All deformed reinforcing bars shall be permanently marked with raised deformations and mill identification marks, in accordance with ASTM A615, A706, A1035, or the applicable specification, so that bar grade, producing mill, and bar size can be determined from visual inspection at the project site.
5.5.2 Bars that cannot be positively identified shall be rejected or tested to confirm grade before incorporation into the work.
5.5.3 Epoxy-coated bars shall retain legible identification marks through the coating; where marks are obscured, the bar ends shall be tagged or color-coded in accordance with the ASTM standard and the coater's identification system.
6 Fabrication
6.1 General Requirements
6.1.1 Reinforcing bars shall be fabricated in accordance with the reviewed shop drawings, the CRSI Manual of Standard Practice, and the applicable ASTM material specification.
6.1.2 Fabrication shall include all cutting to length, bending, assembly of reinforcement cages, and application of identification tags.
6.1.3 Bars shall be fabricated to the standard bending tolerances of the CRSI Manual of Standard Practice; dimensions flagged as "Critical" on the shop drawings shall be held to the tighter tolerances noted there.
6.1.4 Bars shall not be re-bent or straightened in a manner that damages the steel.
6.1.5 Cold-bending of bars in the field is permitted only for minor adjustments and shall not be done for No. 8 bars and larger without written approval of the Engineer of Record and compliance with ACI 318-19 Section 26.6.2.
6.2 Bending Requirements
NOTE The minimum inside bend diameters for standard hooks are: No. 3 through No. 8 bars — 6db (where db is the nominal bar diameter); No. 9, 10, and 11 bars — 8db; No. 14 and 18 bars — 10db. (6.2.1)
● Per ACI 318-19 Table 25.3.2 — confirmed by fabricator
Per drawings — structural drawings
6.2.2 All bars shall be cold-bent.
6.2.3 Hot bending is not permitted unless approved in writing by the Engineer of Record and accompanied by heat treatment to restore properties.
6.2.4 Standard hooks shall be formed to the minimum inside bend diameters specified in ACI 318-19 Table 25.3.1 and detailed in the CRSI Manual of Standard Practice.
6.2.5 Stirrups and ties shall follow the reduced bend diameter requirements of ACI 318-19 Table 25.3.2.
NOTE Bends of less than these minimum diameters crack the bar surface and damage the transverse deformations, reducing both tensile capacity and bond to concrete. (6.2.6)
6.3 Fabrication Tolerances
NOTE Standard fabrication tolerances, as given in the CRSI Manual of Standard Practice, apply to all bars unless the shop drawings designate specific dimensions as Critical. (6.3.1)
6.3.2 Fabrication tolerances shall be: cut length — ±1 in.; overall bent length of bar — ±1 in.; depth of stirrups, ties, and spirals — ±3/8 in.; location of bends — ±1 in.
6.3.3 Dimensions flagged as Critical shall be held to ±1/4 in.
6.3.4 Where bar positions are critical — for example, in precast elements, in elements with post-tensioning ducts, or in elements with closely spaced bars — the sum of fabrication and placement tolerances shall be evaluated to confirm that specified cover is achievable.
NOTE Fabrication tolerances accumulate with placement tolerances. (6.3.5)
6.4.1 Where headed bars are specified for development, discontinuation at walls or discontinuous edges, or connections to precast elements, heads shall be forged or mechanically attached.
● Not required
○ Required — ASTM A970 Class A (no head obstructions)
○ Required — ASTM A970 Class B (obstructions permitted)
○ Required — element designations per Contract Drawings
6.4.2 Heads for headed bars shall be forged or mechanically attached and shall conform to ASTM A970/A970M.
6.4.3 The bearing area of the head shall be not less than four times the cross-sectional area of the bar, in accordance with ACI 318-19 Section 25.4.4, unless a larger ratio is required on the Contract Drawings.
6.5 Protection of Fabricated Steel
6.5.1 Fabricated reinforcing steel shall be stored above grade on supports that keep bars free of mud, debris, and standing water.
6.5.2 Bars coated with mud or other deleterious material shall be cleaned before placement.
6.5.3 Bars with heavy flaking rust, pitting, or mill scale that reduces the effective cross-section shall be rejected.
6.5.4 Epoxy-coated and galvanized bars shall be stored in a manner that prevents coating damage, and shall not be stockpiled in direct contact with each other without protective packaging.
NOTE Light surface rust on uncoated bars does not reduce bond to concrete and is not cause for rejection. (6.5.5)
7 Placement and Support
7.1 General Placement Requirements
7.1.1 Reinforcement shall be placed in accordance with the reviewed shop drawings and shall be secured in position before and during concrete placement.
7.1.2 No reinforcing bar shall be moved during concrete placement except under the direct observation and approval of the Engineer of Record.
7.1.3 Bars displaced during concrete placement shall be restored to correct position before the concrete takes initial set.
7.1.4 Bars shall be placed in the positions, at the spacings, and to the concrete cover shown on the Contract Drawings and shop drawings.
7.1.5 Placement shall not deviate from the specified position by more than the tolerances given in ACI 117-10 (see the Tolerances section of this specification).
7.2 Bar Spacing
7.2.1 Minimum clear spacing between parallel bars shall be maintained to permit concrete to pass between bars and thoroughly surround each bar.
3/8 in.
1/2 in.
3/4 in.
1 in.
1-1/2 in.
7.2.2 Minimum clear spacing between parallel bars shall be not less than the bar diameter (db), 1.33 times the nominal maximum aggregate size, and 1 in. per ACI 318-19 Section 25.8.1, with the three requirements applied simultaneously and the controlling requirement governing.
7.2.3 Where bars are placed in two or more layers, bars in the upper layers shall be placed directly above those in the lower layer.
7.2.4 The minimum clear distance between layers shall be 1 in., per ACI 318-19 Section 25.8.1.
7.3 Bar Supports and Chairs
7.3.1 All reinforcing bars shall be supported by bar supports (chairs, bolsters, spacers, or ties) that hold the bars in position within the specified tolerances and resist displacement during concrete placement and consolidation.
Precast concrete block supports
Plastic-tipped wire chairs
All-plastic chairs
Per drawings
Plastic-tipped wire chairs (standard exposed faces)
All-plastic chairs (aggressive exposure or architecturally exposed)
Stainless steel wire supports (immersion or marine exposure)
Per drawings
7.3.2 Bar supports shall conform to CRSI RB4.1, Supports for Reinforcement Used in Concrete.
7.3.3 Bar support type shall be appropriate for the substrate and exposure.
7.3.4 For slabs-on-grade, precast supports (concrete block chairs) or plastic-tipped wire supports may be used where direct contact with soil is unavoidable; plain wire supports shall not rest directly on compactible soil or fill.
NOTE Plain wire supports resting on compactible soil or fill settle and allow bars to drop. (7.3.5)
7.3.6 For elevated slabs and beams, all-plastic, plastic-protected, or stainless-steel-tipped wire supports shall be used at exposed surfaces or where metallic contact at the concrete surface would be visible or objectionable.
7.3.7 For submerged or aggressive-exposure conditions, concrete or corrosion-resistant plastic supports shall be used; bare wire supports shall not be used in marine or de-icing salt exposure.
7.3.8 For No. 5 and smaller bars, support spacing shall not exceed 48 in.; for No. 6 and larger bars, support spacing shall not exceed 60 in., unless the fabricator calculates and demonstrates that sag at the support midpoint remains within tolerance at the specified support spacing.
7.4 Tying of Bars
7.4.1 Bars shall be tied at intersections at sufficient spacing to hold all bars in their correct positions during concrete placement.
● Plastic-coated tie wire for epoxy-coated or galvanized bars
○ Stainless steel tie wire for all corrosion-sensitive elements
○ Standard annealed tie wire — uncoated bars only
7.4.2 Bars shall be tied at intersections at sufficient spacing to hold all bars in their correct positions during concrete placement.
7.4.3 All bar intersections at the perimeter of each mat or cage shall be tied.
7.4.4 Interior intersections shall be tied at every other intersection in a checkerboard pattern, or at closer spacing as directed by the Engineer of Record or Special Inspector when the mat configuration or the vibration conditions require closer tying.
7.4.5 Tie wire shall be annealed iron wire; for epoxy-coated or galvanized bars, plastic-coated or stainless steel tie wire shall be used to avoid contact corrosion and coating damage from cutting tie wire ends.
7.4.6 Tie wire ends shall be bent away from the concrete surface so that the wire tail does not end up within the concrete cover zone.
NOTE A protruding tie wire tail creates a direct corrosion path from the bar to the surface and is one of the most common causes of concrete surface staining and early reinforcement corrosion. (7.4.7)
7.5 Welded Wire Reinforcement Placement
7.5.1 WWR sheets shall be lapped at least one mesh spacing plus 2 in. in each direction, or as required by ACI 318-19 Chapter 25 for the specified spacing and wire grade, whichever is greater.
7.5.2 Where the Contract Drawings require a specific lap, that lap shall govern.
7.5.3 WWR rolls shall be unrolled, lapped, and weighted or tied to prevent spring-back before concrete is placed.
7.5.4 WWR shall not be placed flat and then raised during concrete placement, because pulling wire during placement does not reliably achieve the specified cover and placement position.
8 Concrete Cover
8.1 Cover Requirements
NOTE Concrete cover is the clear distance from the concrete surface to the outer face of the outermost reinforcing bar (including stirrups, ties, or spirals, which are the outermost bars in most beams and columns). (8.1.1)
NOTE Cover requirements are specified in ACI 318-19 Table 20.6.1 and reflect both structural requirements (bond development length depends on cover) and durability requirements (cover is the primary barrier preventing chloride, carbonation, and moisture from reaching the steel). (8.1.2)
3 in. (ACI 318-19 minimum)
3-1/2 in.
4 in.
Per drawings
2 in. (ACI 318-19 minimum)
2-1/2 in.
3 in.
Per drawings
1-1/2 in. (ACI 318-19 minimum)
2 in.
2-1/2 in.
Per drawings
1-1/2 in. (ACI 318-19 minimum)
2 in.
Per drawings
3/4 in. (ACI 318-19 minimum)
1 in.
1-1/2 in.
Per drawings
8.1.3 The minimum concrete cover requirements below apply unless the Contract Drawings specify greater cover, and greater cover than the tabulated minimum shall always govern.
8.1.4 For concrete cast against and permanently exposed to earth (footings, grade beams, pile caps cast against soil), minimum cover shall be 3 in.
8.1.5 For concrete exposed to earth or weather (garage decks, exterior slabs, surfaces in regular contact with moisture or freezing-and-thawing), minimum cover shall be 2 in. for No. 6 through No. 18 bars and 1-1/2 in. for No. 5 bars and smaller.
8.1.6 For concrete not exposed to weather or in contact with ground, primary reinforcement in beams, girders, and columns shall have 1-1/2 in. minimum cover.
8.1.7 For slabs, walls, and joists not exposed to weather or in contact with ground, minimum cover shall be 3/4 in. for No. 5 bars and smaller and 1-1/2 in. for No. 6 through No. 11 bars.
8.1.8 The Engineer of Record shall specify greater cover on the Contract Drawings for elements in high-chloride environments, for elements with large aggregates, for fire-resistance requirements beyond code minimum, or where any other condition warrants increased protection.
8.2 Cover for Coated Reinforcement
8.2.1 For epoxy-coated bars, the specified concrete cover shall not be reduced below the values for uncoated bars, per ACI 318-19.
8.2.2 Galvanized bars shall be placed to the same minimum cover requirements as uncoated bars.
8.2.3 Specifying cover less than the tabulated minimums for coated bars is not permitted.
NOTE The coating reduces the rate of corrosion once chloride reaches the bar, but does not reduce the required minimum cover, which serves the dual purposes of durability and bond development. (8.2.4)
8.3 Fire-Resistance Cover
8.3.1 Where the structural element must satisfy a fire-resistance rating under IBC Chapter 7 or under ACI 216.1, the required concrete cover for fire resistance shall be compared against the cover required for structural and durability purposes.
○ No — structural and durability cover govern
○ Yes — fire-resistance cover per IBC Chapter 7 or ACI 216.1 governs
Per drawings — structural drawings (deferred by default)
8.3.2 Where the structural element must satisfy a fire-resistance rating under IBC Chapter 7 or ACI 216.1, the required concrete cover for fire resistance shall be compared against the cover required for structural and durability purposes, and the greater value shall be used.
8.3.3 The Contract Drawings shall indicate fire-resistance requirements that govern cover.
NOTE For slabs, beams, columns, and walls in high-occupancy buildings, fire-resistance requirements frequently control cover. (8.3.4)
9 Splices and Couplers
9.1 General Requirements
NOTE Splices are necessary whenever bar lengths exceed available mill lengths (typically 60 ft), where construction joints require transition between elements, and where bar congestion or structural analysis requires staged termination of bars. (9.1.1)
9.1.2 Splices shall be designed and located by the Engineer of Record.
9.1.3 The Contractor shall not relocate or add splices without written approval from the Engineer of Record.
9.1.4 Every splice shall either develop the full tensile capacity of the bars being spliced (Type 2 performance, required in ductile seismic zones and frequently specified for critical structural elements) or develop at least 125 percent of the specified yield strength of the bars (Type 1 performance, the code minimum for most non-seismic applications).
9.1.5 The Contract Drawings shall designate which type of performance is required for each splice location.
9.2 Tension Lap Splices
9.2.1 Tension lap splice length shall be determined by the Engineer of Record in accordance with ACI 318-19 Sections 25.5.2 and 25.5.7, based on the development length (ld) for the bar in the given concrete strength and cover condition, and the class of splice.
● Class B (1.3 × ld) — conservative default, all conditions
○ Class A (1.0 × ld) where permitted by ACI 318-19 — per Contract Drawings
Per drawings
Calculated per ACI 318-19 — shown in lap splice schedule on drawings
Per drawings — lap splice schedule (deferred by default)
9.2.2 A Class A tension lap splice (1.0 × ld) is permitted when at most 50 percent of the bars within the lap splice length are spliced and the provided area of reinforcement is at least twice the required area.
9.2.3 A Class B tension lap splice (1.3 × ld) is required in all other cases, including where more than 50 percent of the bars are spliced at the same cross-section.
9.2.4 The default for this specification shall be Class B unless the Engineer of Record specifically designates Class A on the Contract Drawings.
9.2.5 Lap splices are not permitted for No. 14 and No. 18 bars; for these bar sizes, mechanical couplers or welded splices shall be used.
9.2.6 Lap splices in bars subjected to direct compression (columns, piers) shall follow compression lap splice requirements per ACI 318-19 Section 25.5.5.
NOTE Class B is more conservative, is independent of the staggering condition, and reduces the risk of errors when splice staggering is not strictly maintained in the field. (9.2.7)
9.3 Compression Lap Splices
9.3.1 For bars in pure compression (columns, pedestals, compression zone of beams), the compression lap splice length shall be not less than the larger of 0.0005 × fy × db (in.) and 12 in., per ACI 318-19 Section 25.5.5.1, where fy is the specified yield strength in psi and db is the nominal bar diameter in inches.
9.3.2 Where ties or spirals enclose compression splices, reduced compression splice lengths may be permitted per ACI 318-19 Table 25.5.5.2 when approved by the Engineer of Record.
NOTE For Grade 60 bars, 0.0005 × 60,000 × db gives 30db, with a 12 in. minimum. (9.3.3)
9.4 Mechanical Couplers
9.4.1 Where the Contract Drawings designate mechanical splices, couplers shall be installed in accordance with the reviewed product data and the manufacturer's installation instructions.
9.4.2 Coupler type and performance classification shall be as specified on the Contract Drawings.
Type 1 only — 125% of fy (non-seismic applications)
Type 2 only — 125% of fy + full tensile strength (seismic applications)
Both — Type 1 standard elements, Type 2 seismic elements per Contract Drawings
Not used — lap splices and welded splices only
Per drawings
○ Contractor self-verification per manufacturer instructions
○ Special Inspector observation required at all couplers
● Special Inspector observation required at seismic elements; self-verification elsewhere
9.4.3 A Type 1 mechanical splice shall develop at least 125 percent of the specified yield strength of the bar in tension and compression.
9.4.4 A Type 2 mechanical splice shall develop at least 125 percent of the specified yield strength and shall also develop the specified tensile strength (ultimate capacity) of the bar.
9.4.5 Type 2 splices are required by ACI 318-19 for specific locations in special moment frames, special structural walls, and other seismic elements where the connection must remain effective after the bar yields.
9.4.6 The Contractor shall not substitute a different coupler type without written approval from the Engineer of Record.
NOTE The Type 1 versus Type 2 distinction reflects a structural design decision, not an installer preference. (9.4.7)
9.5 End-Bearing Compression Splices
NOTE End-bearing compression splices, in which bars are cut square and the ends bear in direct contact to transfer compression, are permitted for No. 10 bars and larger in pure compression applications where approved by the Engineer of Record. (9.5.1)
9.5.2 End-bearing compression splices are permitted for No. 10 bars and larger in pure compression applications where approved by the Engineer of Record.
9.5.3 Bars shall be cut so that end bearing surfaces are within 1.5 degrees of perpendicular to the bar axis.
9.5.4 An end-bearing splice shall be restrained against lateral displacement by ties or other means at each end of the splice.
9.5.5 End-bearing splices shall not be used in tension zones or where bars experience reversing stresses.
10 Welding of Reinforcement
10.1 General Policy
10.1.1 Field welding of reinforcing bars shall be minimized and shall be permitted only where specifically required by the Contract Drawings or approved in writing by the Engineer of Record.
NOTE Welding is not a substitute for proper lap splice length or mechanical coupler installation, and it introduces heat that can alter bar metallurgy and reduce ductility. (10.1.2)
10.2 Weldability Requirements
10.2.1 Only bars verified as weldable shall be field-welded.
● Not permitted — mechanical couplers or lap splices shall be used for all connections
○ Permitted — ASTM A706 bars only, per Contract Drawings
○ Permitted — ASTM A615 and A706, with chemical analysis and preheat per AWS D1.4
Per drawings
10.2.2 Only bars verified as weldable shall be field-welded.
10.2.3 ASTM A706 bars are weldable by specification and may be welded without chemical analysis.
10.2.4 ASTM A615 bars shall require carbon equivalent testing of each heat before welding to determine preheat requirements per AWS D1.4.
10.2.5 ASTM A1035 bars shall not be welded unless the Engineer of Record, the fabricator, and the AWS D1.4 qualified welding engineer have all reviewed and approved a specific welding procedure specification (WPS).
10.3 Welding Procedure Specifications
10.3.1 All welding shall be performed in accordance with a Welding Procedure Specification (WPS) qualified in accordance with AWS D1.4/D1.4M.
10.3.2 The WPS shall address base metal grade and carbon equivalent range, filler metal classification, preheat and interpass temperature, joint geometry, welding process, and position.
10.3.3 Welding shall not begin until the WPS has been submitted to and reviewed by the Engineer of Record.
10.3.4 Preheat temperatures shall be maintained throughout the welding operation and not relaxed until the weld is complete and allowed to cool per the WPS.
10.4 Qualified Welders
10.4.1 Welding operators shall be certified to AWS D1.4 for the welding process and positions used.
10.4.2 Certification records shall be current (within three years) and available to the Special Inspector on request.
10.4.3 Tack welding of bars in position shall not be performed by uncertified workers.
10.5 Prohibited Welding
NOTE The following practices are prohibited without exception. (10.5.1)
10.5.2 Welding to any bar unless it is confirmed weldable per the requirements above is prohibited.
10.5.3 Welding of crossing bars (tack welding of tie intersections to act as permanent connections) is prohibited unless specifically designed as welded connections by the Engineer of Record.
10.5.4 Weld splices where lap splices or mechanical couplers are required on the Contract Drawings are prohibited.
10.5.5 Welding of any bar with visible cracks, seams, or surface defects is prohibited.
11 Tolerances
11.1 Reinforcement Placement Tolerances
11.1.1 Tolerances for placement of reinforcing steel shall be as specified in ACI 117-10.
NOTE The following apply to nonprestressed reinforcement. (11.1.2)
● Per ACI 117: not to exceed 1/3 specified cover, and no more than 1/4 in. for formed soffits
Per drawings
11.1.3 For effective depth (d) and clear cover to formed surfaces, the tolerance shall be ±3/8 in. where d ≤ 8 in., ±1/2 in. where d > 8 in. and ≤ 24 in., and ±1 in. where d > 24 in., applied to the position of the bar measured from the relevant reference face.
11.1.4 The reduction in concrete cover shall not exceed one-third of the specified concrete cover, and the reduction in cover to formed soffits shall not exceed 1/4 in., per ACI 117.
11.1.5 The longitudinal position of bends and bar ends shall be within ±2 in. except at discontinuous ends where the tolerance is ±1/2 in.
11.1.6 Spacing between bars shall be within ±1/4 in. for bars at 12 in. on center or less and ±1/2 in. for bars at more than 12 in. on center.
NOTE The placement target is the specified position; tolerances are a range that may not be deliberately approached. (11.1.7)
NOTE The ACI 318-19 tolerances on effective depth are design check tolerances reflecting the expected range in which a well-built element may differ from the design drawing, used in strength calculations, and are not instructions to place bars at the extreme tolerance limit. (11.1.8)
11.2 Splice and Development Length Tolerances
11.2.1 Lap splice lengths and development lengths shall meet the specified minimum; no negative tolerance is permitted for development length or lap splice length.
11.2.2 The Contractor shall ensure that bars are long enough, and that stagger is maintained, so that every bar develops its required capacity.
NOTE A lap splice that is 1/2 in. short of the specified length is a nonconformance requiring Engineering evaluation regardless of the ACI 117 position tolerances. (11.2.3)
11.3 Bar Size and Substitution
11.3.1 Bar size substitution shall not be made without written approval of the Engineer of Record.
NOTE Substituting a smaller number of larger bars for a larger number of smaller bars, or vice versa, changes the development length, bar spacing, concrete cover, and cracking behavior of the element, which are interdependent and require Engineering analysis before any substitution. (11.3.2)
12 Field Inspection
12.1 Pre-Placement Inspection
12.1.1 Before any concrete is placed, the Contractor shall perform a pre-placement inspection of all reinforcement in the element.
● Yes — Contractor checklist plus Special Inspector observation report
○ Yes — Special Inspector observation report only
○ Yes — Contractor checklist only (where no special inspection required)
12.1.2 Before any concrete is placed, the Contractor shall perform a pre-placement inspection of all reinforcement in the element and shall confirm that bar grades and sizes match the shop drawings; bars are clean, properly positioned, and secured; cover is correct at all locations; lap splices are at correct locations and of correct length; mechanical couplers are fully engaged per manufacturer requirements; bar supports are correctly placed and of the specified type; tie wire tails are bent inward; and there are no displaced, bent, or cut bars that deviate from the shop drawings.
12.1.3 The pre-placement inspection shall be documented on a checklist, and for elements subject to special inspection the Special Inspector's observation shall be recorded.
12.1.4 Concrete shall not be placed until the pre-placement inspection is complete and any deficiencies are corrected.
12.2 Special Inspector Responsibilities
12.2.1 The Special Inspector for reinforcing steel shall perform the following at minimum, in accordance with the Statement of Special Inspections.
Continuous during reinforcement placement and concrete pour
Periodic (verify placement prior to pour; available during pour)
Per Statement of Special Inspections
12.2.2 The Special Inspector shall verify that reinforcing bar grade and size match the Contract Documents and reviewed shop drawings, identifying bars by their deformation markings, and shall place no bar without positive identification of grade.
12.2.3 The Special Inspector shall measure concrete cover at representative locations — at top, bottom, and side faces of each element — record the measured values, and immediately notify the Engineer of Record where cover measurements indicate a potential violation of the ACI 117 tolerance.
12.2.4 The Special Inspector shall verify lap splice lengths by measuring each splice in the element between bar ends, not including the bend of a hook in the measurement.
12.2.5 The Special Inspector shall inspect mechanical couplers to confirm they are fully engaged — verifying that the inspection hole on threaded couplers shows the bar end, that lock pins or set screws are tightened to the manufacturer's specified torque, and that no cross-threading or partial engagement is visible.
12.2.6 The Special Inspector shall verify that WWR laps are correct and that the sheets or rolls are at the correct elevation and properly supported.
12.2.7 The Special Inspector shall observe welded splices and connections to confirm that welding is performed by a certified operator using a reviewed WPS and that visible weld quality meets AWS D1.4.
12.3 Cover Measurement
12.3.1 The Special Inspector shall measure concrete cover using a calibrated cover meter (pachometer) at representative points on the placed reinforcement.
12.3.2 Measurements shall be taken at top bars in slabs (measuring from slab top surface to top bar if accessible, or from bottom surface to bottom bar), at slab and beam sides for side cover, and at beam soffits for bottom cover.
12.3.3 Measurements shall be compared against the specified cover and the ACI 117 tolerance.
12.3.4 Any measurement below the minimum cover minus the allowable tolerance shall be reported immediately and corrected before concrete is placed.
12.4 Bar Placement Documentation
12.4.1 The Special Inspector shall record measured bar spacing at representative locations, measured center-to-center at not less than three locations per element.
12.4.2 The recorded spacings shall be compared against the specified spacing with the ACI 117 tolerance applied.
NOTE Excess bar spacing weakens sections and increases crack width; deficient bar spacing can produce congestion that prevents concrete from flowing between bars. (12.4.3)
12.5.1 Any reinforcement that does not conform to the Contract Documents, the reviewed shop drawings, or the requirements of ACI 318-19 and ACI 117 shall be documented as a nonconformance.
12.5.2 Any reinforcement that does not conform to the Contract Documents, the reviewed shop drawings, or the requirements of ACI 318-19 and ACI 117 shall be documented as a nonconformance by the Special Inspector and reported to the Engineer of Record, the Contractor, and the Owner in writing before concrete is placed.
12.5.3 Concrete shall not be placed over a documented nonconformance until the Engineer of Record has reviewed it and issued a written disposition.
12.5.4 Dispositions shall be one of: reject and correct; accept as-is with justification (Engineering evaluation required); or accept with compensating action (added bars, reduced loads, or other mitigation).
12.6 Concrete Pour Monitoring
12.6.1 During concrete placement, the Contractor shall assign a qualified individual to monitor reinforcement for displacement.
12.6.2 Concrete vibrators shall not be used against reinforcing bars as a means of vibration; internal vibrators shall be inserted between bars and shall be operated in a manner that does not drag or dislodge bar mats.
12.6.3 If reinforcement is displaced during placement, work shall be stopped, the bar shall be restored to position, and the cause of displacement shall be corrected before placement resumes.
13 Delivery, Storage, and Handling
13.1 Delivery
13.1.1 Reinforcing steel shall be delivered to the project site in clearly labeled bundles identified by bar mark, size, grade, coating type, heat number, and quantity.
13.1.2 Bundles shall carry certification tags that match the CMTRs submitted under the Submittals section.
13.1.3 Bars shall not be accepted without traceable certification.
13.2 Storage on Site
13.2.1 Bars shall be stored above grade on timber or other supports that keep bars clear of mud, standing water, and road dirt.
13.2.2 Bars shall be stored in a manner that does not impose bending loads on fabricated shapes, and stirrups and small fabricated cages shall be supported to prevent permanent distortion.
13.2.3 Epoxy-coated bars shall be stored in their original packaging or under protective covering to prevent UV degradation of the coating.
13.2.4 Galvanized bars shall be stored so that bundled bars do not develop wet-storage staining (white rust), by allowing adequate air circulation between bars.
13.3 Handling
13.3.1 Bars shall be lifted and handled using nylon slings or other methods that do not score, nick, or damage the bar surface or coating.
13.3.2 Wire rope slings shall not be used directly on epoxy-coated or galvanized bars.
13.3.3 Bars shall not be dropped from height onto hard surfaces, because impact can crack epoxy coatings and cause bar deformation at bends.
14 Warranty
14.1 Installation Warranty
14.1.1 The Contractor shall warrant the reinforcement installation against defects in workmanship for the project warranty period.
1 year from substantial completion
2 years from substantial completion
14.1.2 The Contractor shall warrant the reinforcement installation against defects in workmanship — including incorrect bar grades, inadequate cover, insufficient splice length, and improper coupler installation — for the project warranty period.
14.1.3 The warranty shall not limit the Engineer of Record's right to perform special inspection, to require corrective work for nonconforming conditions, or to require the Contractor to expose and remediate reinforcement that was placed in a noncompliant condition.
14.2 Material Warranties
14.2.1 Material warranties provided by the bar manufacturer or the coating applicator shall be passed through to the Owner.
14.2.2 For epoxy-coated bars, the coater's warranty against coating delamination (where provided) shall be documented and included in the closeout submittals.