1 Scope

NOTE This standard governs cast-in-place anchor rods, headed anchor bolts, and embedded steel items that are set into concrete substructures before or during concrete placement to anchor structural steel and equipment. (1.1)

NOTE The covered items include straight, headed, and hooked anchor rods; bearing plates and washer plates at the embedded end; embedded plates (embed plates) with welded studs or bar anchors; pipe sleeves for adjustable anchorage; weld studs; leveling-nut assemblies; and the templates used to hold an anchor group in position during the pour. The common thread is that every item is committed to the concrete at the time of the pour and cannot be relocated afterward without destructive work. (1.2)

NOTE This standard covers the material specification, fabrication, protective coating, setting, and field inspection of cast-in anchorage on commercial, industrial, institutional, and heavy civil projects. (1.3)

NOTE Typical anchored elements are structural steel columns, equipment and machinery bases, canopy posts, sign supports, light and utility poles, and similar elements that must be positively tied to concrete foundations, grade beams, piers, or walls. The standard addresses what is furnished, how it is identified and coated, how it is held in position, and how the installed assembly is verified before and after the pour. (1.4)

1.5 Anchor rod diameter, embedment depth, grade, and group geometry shall be as shown on the structural drawings and shall not be substituted without written approval of the Engineer of Record.

NOTE This standard specifies materials, fabrication quality, coatings, setting tolerances, and inspection. It does not size anchors. Concrete anchor capacity (breakout, pullout, pryout, and side-face blowout) is a design responsibility of the Engineer of Record under ACI 318-19 Chapter 17, and the rod diameter, effective embedment, and spacing that result from that design are given on the drawings. (1.6)

NOTE Post-installed expansion, screw, and adhesive anchors are not covered by this standard. (1.7)

NOTE Post-installed anchors are contractor-selected proprietary products governed by ACI 318-19 Chapter 17 and an ICC-ES evaluation report (ESR); their qualification, edge distance, and installation differ fundamentally from cast-in items. (1.8)

1.9 A post-installed anchor proposed to correct or supplement cast-in anchorage shall be reviewed and approved by the Engineer of Record before use.

NOTE Base-plate bearing, grout pockets, and the leveling procedure that follows anchor installation are covered by companion standards. (1.10)

NOTE Setting of the base plate to elevation, the grout space below it, and the non-shrink grout itself are addressed in Grouted Base PlatesGrouted Column Base Plates and Bearing PlatesResolves to the current edition.sync/grouted-base-plates and Non Shrink GroutNon-Shrink GroutResolves to the current edition.sync/non-shrink-grout. Steel frame erection, framing tolerances, and connection design above the base plate are addressed in Structural Steel FramingStructural Steel FramingResolves to the current edition.sync/structural-steel-framing and Structural Steel ConnectionsStructural Steel ConnectionsResolves to the current edition.sync/structural-steel-connections. Concrete mix, placement, and reinforcement around the anchorage are addressed in Cast In Place ConcreteCast-in-Place ConcreteResolves to the current edition.sync/cast-in-place-concrete and Concrete ReinforcementConcrete ReinforcementResolves to the current edition.sync/concrete-reinforcement. (1.11)

2 Referenced Standards

2.1 Materials, fabrication, coating, welding, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited on the drawings or in this standard.

2.2 Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.

Standard	Title
ASTM F1554-20	Anchor Bolts, Steel, 36, 55, and 105-ksi Yield Strength
ASTM A36/A36M	Carbon Structural Steel
ASTM A108	Steel Bar, Carbon and Alloy, Cold-Finished
ASTM A307	Carbon Steel Bolts, Studs, and Threaded Rod 60,000 PSI Tensile Strength
ASTM A563	Carbon and Alloy Steel Nuts
ASTM F436/F436M	Hardened Steel Washers for Fastening Structural Members
ASTM A153/A153M	Zinc Coating (Hot-Dip) on Iron and Steel Hardware
ASTM B695	Coatings of Zinc Mechanically Deposited on Iron and Steel
AWS D1.1/D1.1M	Structural Welding Code — Steel
AWS D1.4/D1.4M	Structural Welding Code — Reinforcing Steel
ACI 318-19	Building Code Requirements for Structural Concrete (Chapter 17)
ACI 117-10	Specification for Tolerances for Concrete Construction and Materials
AISC 360-22	Specification for Structural Steel Buildings
AISC 303-22	Code of Standard Practice for Steel Buildings and Bridges
AISC Design Guide 1	Base Plate and Anchor Rod Design (2nd Edition)
IBC 2021	International Building Code (Section 1705.12)

3 Submittals

3.1 Action Submittals

3.1.1 The Contractor shall submit the following action items for review before fabrication and before any concrete placement that embeds anchorage:

Shop drawings showing each anchor rod and embed type, with diameter, total length, embedment depth, head or hook configuration, thread length, and group layout keyed to column or equipment marks.
Setting plans showing plan position, orientation, and elevation of every anchor group, with the datum and grid lines used for layout.
Template drawings identifying template material, the anchor groups each template serves, and the party furnishing the template.
Mill test reports and product certification for anchor rods, nuts, washers, weld studs, and embed plate material, including ASTM F1554 grade and color code.
Galvanizing or coating certification, including coating weight and confirmation of thread re-chasing where threaded ends are galvanized.
Welding documentation for shop-welded embeds and weld studs, including welder qualification and weld procedure specifications per AWS D1.1.

Action submittals requiredcheckbox

☑ Anchor rod and embed shop drawings

☑ Anchor setting plans (plan position and elevation)

☐ Setting template drawings

☑ Mill test reports and product certification

☐ Galvanizing / coating certification

☐ Welding documentation (procedures and welder qualification)

3.2 Informational Submittals

3.2.1 The Contractor shall submit the following informational items for record:

Manufacturer product data for proprietary weld studs and pre-assembled pipe-sleeve assemblies.
Coating applicator qualification for hot-dip galvanizing or mechanical zinc deposition.
Anchor rod tensioning or snug-tightening procedure where the structural drawings call for pretensioned anchorage.

Informational submittals requiredcheckbox

☑ Weld stud and pipe-sleeve product data

☐ Coating applicator qualification

☐ Anchor tensioning / snug-tightening procedure

3.3 Closeout Submittals

3.3.1 The Contractor shall submit the following closeout items before steel erection over the anchorage:

As-set survey of each anchor group documenting actual plan position and top-of-rod elevation against the specified tolerance.
Special inspection reports for anchor installation where required by IBC Section 1705.12.
Field reports documenting correction of any anchor placed outside tolerance, including the Engineer of Record approval for each correction.

Closeout submittals requiredcheckbox

☑ As-set anchor survey vs. tolerance

☑ Special inspection reports (IBC 1705.12)

☐ Out-of-tolerance correction records with EOR approval

4 Quality Assurance

4.1 Responsibility for Furnishing and Setting

4.1.1 The responsibility for furnishing anchor rods and embeds and the responsibility for setting and inspecting them shall be assigned explicitly in the contract documents.

Anchor rod and embed furnishing responsibilityradio

● Structural steel contractor furnishes; GC sets and inspects

○ Structural steel contractor furnishes and sets

○ GC furnishes and sets

NOTE AISC 303-22 assigns furnishing of anchor rods to the structural steel contractor but assigns setting and inspection to the General Contractor unless noted otherwise. Because the responsibilities split between two parties, an unstated assignment is a common source of anchor rods missing from a bid package or double-counted. The default below should be confirmed against the project coordination requirements. (4.1.2)

4.1.3 The party setting the anchorage shall lay out, set, and brace each anchor group from the established building datum and grid before concrete placement.

4.1.4 The party furnishing the anchorage shall deliver setting templates, anchor rods, nuts, and washers in time to support the setting party's pour schedule.

4.2 Special Inspection

4.2.1 Special inspection of anchor installation shall be provided where the structure is assigned to Seismic Design Category C, D, E, or F, in accordance with IBC Section 1705.12.

NOTE IBC 2021 Section 1705.12 requires special inspection of the installation of cast-in anchors in concrete for structures in the higher seismic design categories, because anchorage is part of the seismic force-resisting path. The special inspector verifies anchor type, diameter, embedment, position, and concrete placement around the anchorage. (4.2.2)

4.2.3 Continuous special inspection shall be provided during concrete placement at anchor groups where required by the special inspection schedule.

Special inspection level for anchor installationradio

● None required (SDC A or B, non-seismic anchorage)

○ Periodic special inspection

○ Continuous special inspection during placement

Per drawings — Structural drawings — Statement of Special Inspections

4.3 Field Verification of Incoming Material

4.3.1 Each lot of anchor rods shall be verified at delivery against its mill certification and ASTM F1554 color code before installation.

NOTE ASTM F1554 requires color-coding at the exposed end of the rod to identify the grade — blue for Grade 36, yellow for Grade 55, and red for Grade 105. Inspectors unfamiliar with the requirement sometimes accept unlabeled rods, which defeats the field check that the correct grade was furnished. Color code and certification together confirm the grade before the rod is committed to concrete. (4.3.2)

4.3.3 Anchor rods delivered without the ASTM F1554 grade color code shall be rejected unless the grade is otherwise certified and verified by the Engineer of Record.

5 Environmental and Service Conditions

5.1 Exposure and Corrosion Environment

5.1.1 The protective coating for anchor rods and embeds shall be selected for the service exposure of the installed assembly.

Service exposure for anchorageradio

● Dry interior, encased in concrete or grout

○ Exterior exposed or intermittently wet

○ Subgrade with soil moisture contact

○ Corrosive industrial / chemical atmosphere

NOTE Uncoated carbon steel is acceptable where the anchorage is permanently encased in concrete or non-shrink grout in a dry interior environment, because the surrounding alkaline cementitious cover passivates the steel. Exterior exposed conditions, subgrade conditions with intermittent moisture, and corrosive industrial atmospheres require a sacrificial or barrier coating to reach the design service life. (5.1.2)

5.1.3 Anchorage exposed to de-icing salts, marine atmosphere, or process chemicals shall be coated and detailed for that environment as directed by the Engineer of Record.

6 Anchor Rod Material and Grade

6.1 Grade Selection

6.1.1 Anchor rods shall be ASTM F1554 of the grade shown on the structural drawings.

Anchor rod material grade (ASTM F1554)radio

● Grade 36 (Fy 36 ksi, Fu 58 ksi) — blue

○ Grade 55 (Fy 55 ksi, Fu 75 ksi) — yellow

○ Grade 105 (Fy 105 ksi, Fu 125 ksi) — red

NOTE ASTM F1554 is the primary material standard for cast-in anchor rods. It defines three yield grades, permits headed, hooked, and straight threaded-and-nutted configurations, addresses weldability through a supplementary requirement, and mandates color-code identification of the grade. Grade 36 (Fy 36 ksi minimum, Fu 58 ksi minimum) is the routine default for column bases, canopy posts, and light equipment. Grade 55 (Fy 55 ksi minimum, Fu 75 ksi minimum) suits higher loads or a reduced rod count. Grade 105 (Fy 105 ksi minimum, Fu 125 ksi minimum) suits high-load moment-frame and heavy equipment bases. (6.1.2)

6.1.3 Grade 105 anchor rods shall not be used as the primary ductile anchorage element in structures assigned to Seismic Design Category C or higher unless supplemental ductility is provided in accordance with ACI 318-19 §17.10.5.3.

NOTE ACI 318-19 §17.10.5.3 restricts high-strength anchors as the governing ductile element in seismic applications, because the higher yield strength reduces the margin between the anchor's tensile capacity and the concrete breakout capacity, inviting a non-ductile concrete failure. Grade 105 is frequently over-specified by designers unfamiliar with this restriction. Where high anchor strength is needed in a seismic structure, ductility must come from a stretch length, a designed yielding mechanism, or another path approved by the Engineer of Record. (6.1.4)

6.1.5 Where legacy contract documents call for ASTM A36 bent-bar anchors, ASTM F1554 Grade 36 shall be furnished as the equivalent current designation unless the Engineer of Record directs otherwise.

NOTE ASTM A36 was historically used for fabricated bent-bar anchors and embedded plates and still appears in some legacy documents. ASTM F1554 Grade 36 is the current preferred designation for anchor rods, carries the same nominal strength, and adds the grade color code and configuration definitions that A36 lacks. ASTM A307 is sometimes referenced for low-stress anchor applications but is less preferred than F1554 for primary structural anchors. (6.1.6)

6.2 Weldability

6.2.1 ASTM F1554 Supplementary Requirement S1 (weldability) shall be specified for any anchor rod that will be field-welded or that will be shop-welded to a base plate or embed plate, and for all Grade 55 rods that are to be welded.

Weldability supplement (ASTM F1554 S1)radio

● Not required (anchor rod not welded)

○ Supplementary Requirement S1 (weldable) required

NOTE The base F1554 specification does not control chemistry for weldability. Without Supplementary Requirement S1, the carbon equivalent of a Grade 55 rod is uncontrolled, AWS D1.1 prequalified procedures do not apply, and a sound weld cannot be assured. Specifying S1 is the only way to obtain a weldable Grade 55 rod and is required wherever heat will be applied to the anchorage. (6.2.2)

6.2.3 Field welding of anchor rods to base plates or embeds shall conform to AWS D1.1.

6.2.4 Welding of anchor rods or embed plates to reinforcing bars shall conform to AWS D1.4.

7 Configuration and End Detailing

7.1 Head and Anchorage Configuration

7.1.1 Anchor rods shall be furnished in the head or hook configuration shown on the structural drawings.

Anchorage end configurationradio

● Headed (heavy hex head)

○ Straight, threaded-and-nutted with plate washer

○ L-bolt / J-hook (hooked)

NOTE Three configurations are in common use. A headed anchor rod develops its tension through bearing of a forged or heavy hex head on the concrete and is the standard column-base choice. An L-bolt or J-hook develops tension through the hooked leg and suits masonry ledger angles, light equipment pads, and sign bases. A straight threaded-and-nutted rod develops tension through a heavy hex nut bearing on a plate washer at the embedded end and is used where a positive, calculable bearing area is wanted. Hooked anchors have lower and less reliable pullout capacity than headed or nutted anchors and are not interchangeable with them. (7.1.2)

7.1.3 The embedded end of a straight threaded-and-nutted anchor rod shall bear on a plate washer and heavy hex nut sized to develop the required pullout capacity.

7.2 Thread Length

7.2.1 The minimum exposed thread length above the top of concrete shall be shown on the drawings and shall accommodate the full leveling-nut and base-plate stack.

NOTE A fabricator left to a default will furnish the minimum thread, and insufficient exposed thread is discovered only after the concrete is poured — a defect whose remedy is costly core-drilling or a threaded coupler repair. The exposed thread must clear the base-plate thickness, the leveling nut, the top heavy hex nut, the washer, and a tolerance allowance. Coordinating thread length with the actual base-plate and leveling-nut stack is one of the highest-value details in this standard. (7.2.2)

7.2.3 Exposed thread length shall equal the base-plate thickness plus the leveling-nut height plus the top heavy hex nut height plus the washer thickness plus a minimum 1/4 in. allowance.

7.2.4 Anchor rod threads shall extend at least 2 in. below the top of concrete into the embedment so that a top nut can be run down past the concrete surface during setting.

Exposed thread length above top of concreterange

in

212

Per drawings — Anchor rod schedule

8 Protective Coating

8.1 Coating Type

8.1.1 The anchor rod coating shall be as scheduled on the drawings and shall match the service exposure.

Anchor rod protective coatingradio

● Uncoated (encased, dry interior)

○ Hot-dip galvanized per ASTM A153 Class C

○ Mechanically deposited zinc per ASTM B695

○ Epoxy coated (corrosive environment)

NOTE Uncoated carbon steel is the standard where the rod is permanently encased in concrete or grout in a dry interior. Hot-dip galvanizing per ASTM A153 is the standard for exterior exposed and wet conditions. Mechanically deposited zinc per ASTM B695 is an alternative where hydrogen embrittlement of higher-strength rod is a concern. Epoxy coating is reserved for highly corrosive environments. The coating choice follows from the service-exposure selection made earlier and from the Engineer of Record's corrosion allowance. (8.1.2)

8.1.3 Hot-dip galvanized anchor rods shall receive a minimum coating of 1.0 oz/ft² (3.0 mil) zinc in accordance with ASTM A153 Class C.

8.2 Thread Treatment After Galvanizing

8.2.1 Threads on galvanized anchor rods shall be re-chased after galvanizing, or the mating nuts shall be tapped oversize and lubricated, so that the nut runs freely the full length of the exposed thread.

NOTE Hot-dip galvanizing deposits zinc that builds up in the thread roots and crests and can prevent nut engagement. The standard remedies are to re-cut (re-chase) the bolt thread after coating or to overtap the nut to accommodate the coating thickness. If neither is specified, the field discovers that nuts will not run down the rod after the concrete is poured, when correction is most expensive. (8.2.2)

8.2.3 Galvanized nuts shall be matched to galvanized rods from the same coating process so that thread fit is maintained.

9 Nuts, Washers, and Leveling Assemblies

9.1 Nuts and Washers

9.1.1 Nuts shall be heavy hex nuts conforming to ASTM A563, of the grade matched to the anchor rod grade.

Heavy hex nut grade (ASTM A563)radio

○ Grade A (low-stress / Grade 36)

● Grade C (Grade 36 / Grade 55)

○ Grade DH (Grade 105)

NOTE ASTM A563 Grade C is the common nut grade for ASTM F1554 Grade 36 anchor rods, and Grade DH is matched to Grade 105 rods to develop the higher rod strength. Matching the nut grade to the rod grade ensures the nut does not strip before the rod reaches its design tension. Washers under leveling nuts and top nuts conform to ASTM F436. (9.1.2)

9.1.3 Hardened washers conforming to ASTM F436 shall be provided under each leveling nut and each top nut bearing on a base plate.

9.2 Double-Nut Leveling Assembly

9.2.1 A double-nut leveling assembly shall be provided where the base plate must be set to a precise elevation before grouting, as shown on the drawings.

Anchor rod nut configuration at base plateradio

● Single top nut (plate set on concrete or shims)

○ Double-nut leveling (lower nut + plate washer + top nut)

NOTE A leveling-nut configuration places a lower nut and plate washer under the base plate and a top nut above it, so the base plate can be brought to exact elevation and made level before the grout space is filled. This is the standard configuration for precision equipment bases and machinery foundations where the base-plate elevation tolerance is tight. The companion grouting and leveling procedure is in Grouted Base PlatesGrouted Column Base Plates and Bearing PlatesResolves to the current edition.sync/grouted-base-plates. (9.2.2)

9.2.3 The leveling nut and its washer shall remain in place and be embedded in the grout after the base plate is grouted unless the drawings require its removal.

10 Embedded Plates and Weld Studs

10.1 Embedded Plates

10.1.1 Embedded plates shall be fabricated from steel of the grade shown on the drawings, with shop-welded headed studs or deformed bar anchors on the back face for development into the concrete.

Embedded plate materialradio

● ASTM A36

○ ASTM A572 Grade 50

Embedded plate back-face anchorageradio

● Headed weld studs

○ Deformed bar anchors (welded)

○ Bent reinforcing bar anchors (tied)

NOTE Embed plates are cast flush into a wall or slab to provide a weldable steel surface for later attachment of miscellaneous steel. The plate is typically ASTM A36 or ASTM A572 Grade 50, and its anchorage to the concrete is provided by welded headed studs or by deformed reinforcing-bar anchors welded to the back face. The plate size must allow weld access for the connection it will receive and must clear the reinforcing cage and the form face. (10.1.2)

10.1.3 Embedded plates shall be set with sufficient concrete cover and edge distance that the welded studs or bar anchors clear the form face and the reinforcing cage.

NOTE An embed plate set too close to a form leaves insufficient concrete cover over its anchors, and shop-welded studs that conflict with the rebar cage force field fit-up changes at the pour. Edge distance and clearance must be coordinated on the setting plan before the cage is closed, not discovered during placement. (10.1.4)

10.2 Weld Studs

10.2.1 Headed weld studs shall be ASTM A108 cold-finished steel applied by an automatically timed stud welding process in accordance with AWS D1.1.

NOTE Arc-welded headed shear studs are used on composite steel beams and on equipment embed plates to transfer shear into the concrete. The base material is ASTM A108 carbon steel, and the stud is applied with an arc stud-welding gun that produces a full-fusion weld at the base in a single timed cycle. The 3/4 in. and 7/8 in. diameters cover the large majority of composite-beam applications. (10.2.2)

10.2.3 The headed weld stud diameter shall be specified, sized to the shear transfer demand of the composite beam or embed plate.

Headed weld stud diameterradio

○ 1/2 in.

○ 5/8 in.

● 3/4 in.

○ 7/8 in.

10.2.4 Weld studs shall be bend-tested and visually inspected for a full 360° flash at the base in accordance with AWS D1.1 stud welding provisions.

11 Pipe Sleeves and Adjustable Anchorage

11.1 Pipe Sleeve Assemblies

11.1.1 A pipe sleeve assembly shall be provided at anchor groups requiring plan adjustment after concrete placement, as shown on the drawings.

NOTE A pipe sleeve is a section of PVC or steel pipe cast around each anchor rod, leaving the rod free to shift within the sleeve so the group can be brought into alignment after the concrete has cured. After erection the sleeve is filled with non-shrink grout per Non Shrink GroutNon-Shrink GroutResolves to the current edition.sync/non-shrink-grout to lock the rod in its final position. Sleeves are used where the fixed-setting tolerance of a poured-in anchor is too coarse for the equipment or steel being anchored. (11.1.2)

11.1.3 The sleeve inner diameter shall be at least the rod diameter plus 1-1/2 in., providing approximately ±3/4 in. of plan adjustment per side.

11.1.4 Each pipe sleeve shall be sealed at the top before the pour and filled completely with non-shrink grout after the anchored element is set and aligned.

Anchor adjustment methodradio

● Fixed setting (no sleeve)

○ Pipe sleeve, grouted after alignment

Pipe sleeve clearance over rod diameterrange

in

13

11.2 Equipment with Critical Alignment

11.2.1 Equipment requiring alignment tighter than the cast-in setting tolerance shall be anchored with pipe sleeves or shall be set on a sleeved or adjustable anchor system, as directed by the equipment manufacturer and the Engineer of Record.

NOTE Fixed anchor rods poured at the ACI 117 plan tolerance cannot be adjusted after the pour. Rotating equipment such as pumps and compressors with alignment requirements measured in thousandths of an inch must have sleeves, or the owner must accept grouted-in shimming and field re-drilling. The anchoring method must be settled with the equipment requirements before the foundation is detailed. (11.2.2)

12 Setting Templates

12.1 Template Furnishing and Material

12.1.1 Anchor groups shall be set with a template that holds every rod in the group at its correct plan position, spacing, and orientation during concrete placement.

NOTE A template is a jig — wood, steel, or manufactured plastic — that fixes the relative position of the rods in a group so the whole group can be located, leveled, and braced as a unit. A site-built wood template is expendable and inexpensive; a steel template is reusable and precise and is preferred for repeated identical groups and for tight within-group tolerance; a manufactured plastic snap-in template suits standard small groups. The furnishing party is set on the setting plan. (12.1.2)

12.1.3 The setting template material shall be specified, selected for the required reuse, precision, and within-group tolerance of the anchor group.

Setting template materialradio

● Wood (site-built, expendable)

○ Steel (reusable, precise)

○ Manufactured plastic (snap-in)

12.1.4 The party responsible for furnishing the setting template shall be specified on the setting plan.

Setting template furnished byradio

● Structural steel fabricator

○ General Contractor

12.1.5 The template shall be braced against displacement, flotation, and disturbance during concrete placement and shall not be removed until the concrete has gained sufficient strength to hold the anchor group.

13 Setting Tolerances

13.1 Plan, Elevation, and Group Tolerances

13.1.1 Cast-in anchorage shall be set within the tolerances shown on the drawings; where no tighter tolerance is specified, the baseline tolerances of ACI 117-10 shall apply.

Anchor plan-position tolerance (per group center)range

in

0.251

Default: 1 in

Top-of-rod elevation tolerancerange

in

0.52

Default: 2 in

NOTE ACI 117-10 establishes the baseline placement tolerance for embedded anchors: ±1 in. in plan position, ±2 in. in elevation, and ±1/8 in. for the spacing of rods within a single anchor group. These are coarse relative to steel erection. Any tighter tolerance — and within-group tolerance is almost always tightened for column bases — must be stated explicitly, because the fabricator and the setting crew will work to ACI 117 if nothing tighter is given. (13.1.2)

13.1.3 The within-group rod spacing tolerance shall be coordinated with the base-plate hole pattern so that the base plate seats over the as-set rods.

Within-group rod spacing tolerancerange

in

0.06250.25

Default: 0.125 in

NOTE The AISC oversize base-plate hole table assumes that the within-group spacing is held to the tight AISC-recommended tolerance, not the looser ACI 117 plan tolerance for the group as a whole. If the within-group spacing drifts, even an oversize hole may not seat over the misplaced rods. Plan-position tolerance (where the group center lands) and within-group tolerance (how the rods relate to each other) are two different controls, and the second is the one that lets the base plate fit. (13.1.4)

13.2 Base-Plate Hole Coordination

13.2.1 Base-plate anchor rod holes shall be sized in accordance with AISC 360-22 Commentary Table C-J9.1 for the rod diameter.

Base-plate hole oversize over rod diameterradio

● Rod dia. + 5/16 in. (rod ≤ 1 in.)

○ Rod dia. + 1/2 in. (1 in. < rod ≤ 2 in.)

○ Rod dia. + 1 in. (rod > 2 in.)

NOTE Anchor rod holes are made deliberately oversize to absorb setting tolerance: the recommended hole is the rod diameter plus 5/16 in. for rods up to 1 in., plus 1/2 in. for rods over 1 in. through 2 in., and plus 1 in. for rods over 2 in. A plate washer over the oversize hole, welded or loose, transfers the nut bearing across the hole. The oversize holes work only if the within-group spacing tolerance above is also held. (13.2.2)

13.2.3 A plate washer covering the oversize hole shall be provided under the top nut at each anchor rod.

14 Installation

14.1 Layout and Setting

14.1.1 Anchor groups shall be laid out from the established building datum and grid lines using the approved setting plan.

14.1.3 Each anchor group shall be set, leveled, and braced in its template before concrete placement.

14.1.4 Each anchor group shall be checked against the approved setting plan immediately before the pour.

14.1.5 The top of each anchor rod and its threads shall be protected during concrete placement so that concrete, debris, and laitance do not foul the threads.

NOTE Concrete spatter and laitance on the exposed threads prevent the nut from running down and are tedious to clean from a galvanized rod. A cap, tape, or sleeve over the threaded end keeps them clean through the pour and finishing operations. Protection is cheap before the pour and labor-intensive afterward. (14.1.6)

14.2 Verification After Placement

14.2.1 The as-set position and top elevation of every anchor group shall be surveyed after concrete placement and before steel erection.

NOTE The as-set survey is the record that the anchorage landed within tolerance and is the basis for accepting the work or planning a correction. Surveying after the pour, before steel arrives, gives time to address an out-of-tolerance group without holding the erection crew. The survey is a closeout submittal. (14.2.2)

14.2.3 Anchor rods found outside the specified tolerance shall not be bent, heated, or repositioned, and any correction shall be designed or approved by the Engineer of Record before it is performed.

NOTE Field-bending or heating a misplaced anchor rod alters its mechanical properties and its anchorage geometry without analysis, and substituting a post-installed anchor changes the failure mode and the concrete breakout area. Either remedy requires the Engineer of Record to evaluate the corrected condition; a post-installed substitution additionally requires verification against the product's ICC-ES evaluation report. (14.2.4)

14.2.5 Post-installed anchors used to correct or supplement misplaced cast-in rods shall be reviewed and approved by the Engineer of Record before installation.

14.2.6 Post-installed anchors shall be installed in accordance with a valid ICC-ES evaluation report.

15 Delivery, Storage, and Handling

15.1 Protection of Materials

15.1.1 Anchor rods, nuts, washers, and embeds shall be delivered bundled and tagged by mark, with the ASTM F1554 grade color code preserved and legible.

NOTE Mixed grades on a jobsite are a real hazard, because Grade 36, 55, and 105 rods can look identical except for the color code. Keeping rods bundled by mark with the color code intact lets the setting crew and inspector confirm grade at the point of installation. Tagging by mark keeps a group's matched rods, nuts, and washers together. (15.1.2)

15.1.3 Anchor rods shall be stored off the ground on dunnage and protected from mud, de-icing salts, and standing water that would foul threads or initiate corrosion.

15.1.4 Galvanized rods shall be stored so that fresh galvanizing does not develop white-rust staining from trapped moisture between closely stacked rods.

16 Warranty

16.1 Material and Coating Warranty

16.1.1 The Contractor shall warrant that anchor rods, embeds, nuts, washers, and coatings conform to the specified standards and are free of defects in material and workmanship for the project's correction period.

NOTE The anchorage is buried in concrete and cannot be inspected or replaced after the structure is built, so the warranty is effectively for the life of the structure as to defects that could have been caught before the pour. The correction-period warranty covers defects that surface during construction and early occupancy, such as coating failure on exposed rods or nuts that will not engage. (16.1.2)

16.1.3 Defective anchorage discovered during the warranty period shall be corrected by a method approved by the Engineer of Record at no cost to the Owner.