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ANSI/AISC 360-16§J3.6 · Table J3.2Bolt shear only

Steel Connection Bolt Count
Calculator

Calculate the whole-bolt count implied by one edition-specific bolt-shear limit state. The output is not a complete connection design or a final bolt count.

Who it is for: structural engineers checking transparent AISC 360-16 bolt-shear arithmetic after the connection force distribution and applicable edition have been established, at construction documents.

When it cannot answer
The route refuses eccentric or unknown force distribution. Bearing, tearout, block shear, net section, prying, combined tension and shear, slip resistance, spacing, edge distance, connected elements, seismic provisions, and constructability remain separate checks.
AISC 360-16 direct-shear arithmetic
Use only when this edition and scope apply

How to use this calculator

1
Confirm the edition and force distribution
Use this route only for ANSI/AISC 360-16 and a concentrically loaded direct-shear condition already established by analysis.
2
Enter the matched demand
Enter LRFD required strength for LRFD or the applicable ASD load for ASD. Do not mix factored and service-level demand.
3
Select the Table J3.2 condition
Choose the bolt group and whether threads are included in or excluded from the shear plane.
4
Enter shear planes and joint length
The method applies the Table J3.2 footnote reduction when the joint exceeds 38 inches in the direction of load.
5
Check every other limit state
Treat the rounded result as one lower-bound count, not the connection design.

The formula

Ab = πd²/4
Rn = FnvAbnsCj
Available strength: φRn for LRFD or Rn/Ω for ASD.

For the implemented AISC 360-16 bolt-shear limit state, φ = 0.75 and Ω = 2.00. Cj = 0.833 where the joint length in the load direction exceeds 38 inches; otherwise 1.00. Count = ceiling(demand ÷ available strength per bolt).

Worked example

Example
For 80 kips LRFD direct shear, a 3/4-in Group A bolt with threads included, one shear plane, and a 12-in joint: Ab = 0.442 in²; φRn = 0.75 × 54 × 0.442 = 17.9 kips per bolt; the shear-only count is 5. Other limit states can require more bolts or a different layout.

When this estimate will be off

  • ANSI/AISC 360-16 only. Confirm the standard adopted for the project; 2024 IBC references ANSI/AISC 360-22 rather than this edition.
  • Concentric direct shear only. The calculator refuses eccentric, combined, or unknown bolt-group force distributions.
  • Does not check bearing, tearout, block shear, net section, prying, combined tension/shear, slip resistance, spacing, edge distance, connected elements, seismic requirements, or constructability.
  • Threads-excluded selection requires the installed fastener geometry to keep threads out of every applicable shear plane.
  • The count is a single-limit-state lower bound and cannot authorize fabrication or construction.

Frequently asked questions

A common mistake: ANSI/AISC 360-16 only. Confirm the standard adopted for the project; 2024 IBC references ANSI/AISC 360-22 rather than this edition.

Not necessarily. It is only the count implied by bolt shear. The final count and layout must satisfy every applicable connection and detailing requirement.

AISC 360-16 Table J3.2 reduces tabulated shear strength to 83.3% when the fastener pattern exceeds 38 inches in the direction of load because force distribution becomes less uniform.

No. The route fails closed because eccentric loading requires a bolt-group force-distribution analysis that these inputs do not provide.

The built-in Fnv records and factors are explicitly sourced to ANSI/AISC 360-16. Use them only when that edition governs; a later edition should be implemented as a separate versioned rule set.

Sources

Sources and review record

Sources and method basis

Limitations

  • Concentric direct shear and ANSI/AISC 360-16 only; returns one limit-state lower-bound count and excludes all other connection strength, distribution, detailing, seismic, fabrication, and constructability checks.

This free Steel Connection Bolt Count Calculator is built and maintained by DataDrivenAEC, using the relevant codes and standards. It does not substitute for professional judgment.