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LecturesModule 14

Shear Connections

Simple shear tabs, double angles, end-plate shear connections.

AISC Reference Box
  • AISC 360-22 — Specification chapter governing this topic
  • AISC Manual 16th Ed. — Design tables and worked examples

Lecture Notes

This module introduces shear connections. Lecture content here covers the governing physics, LRFD philosophy, and how the relevant AISC 360-22 chapter organizes the limit states.

Instructors can replace this text in Admin Mode. Each section is structured around: (1) behavior, (2) failure modes, (3) AISC limit-state equations, (4) design workflow, (5) detailing requirements.

A short comparison to ASD is included only where the resistance factor / safety factor relationship clarifies the LRFD design check.

Weld (to col)Bolted shear tab — VuLimit states: bolt shear, plate bearing, weld
Shear-tab simple connection — bolt shear, plate bearing, and weld are the governing limit states.

Formula Sheet

NameEquationAISC Ref
Design strengthφ Rn ≥ RuAISC 360-22 B3.1

Worked Example

Shear Connections

Given
Replace with project-specific given data (loads, geometry, material).
Load combination
Controlling LRFD load combination from ASCE 7.
Required strength
Compute required strength Ru from the controlling combination.
Limit states
  • Limit state 1
  • Limit state 2
AISC reference
AISC 360-22 — applicable chapter
Solution steps
  1. 1. Required strength
    Compute Ru.
  2. 2. Trial section
    Pick a trial from AISC shape tables Instructor should verify with official AISC Manual.
  3. 3. Check each limit state
    Apply φ Rn ≥ Ru for every governing limit state.
  4. 4. Iterate
    Resize until the most economical section satisfies all checks.
Final design decision
Select the lightest section that satisfies all LRFD limit states.
Common mistakes in this example
  • Skipping a limit state
  • Using the wrong φ factor
  • Forgetting serviceability checks

FE-Style Worked Examples (6)

Each example mirrors the NCEES FE Civil Reference Handbook style: brief givens, a labeled figure, AISC section reference, step-by-step numeric solution, and a single boxed answer.

Given
PL 3/8×4×1'-0" A36 with 4 rows of 3/4" A325-N bolts.
AISC Reference
AISC Manual Part 10
Step-by-step solution
  1. Bolt shear
    4 × 17.9 = 71.6 k
  2. Plate shear yield
    1.0(0.6×36)(12×0.375) = 97.2 k
  3. Block shear
    Check per §J4.3 with plate geometry
Answer Bolt shear typically governs at 71.6 k.
Mu, VuBolted FR moment connection

Practice Problems

  1. [E] List the three common simple shear connection types.
  2. [E] State that simple shear connections carry no moment.
  3. [E] Three limit states for shear tab: bolt shear, plate bearing, weld.
  4. [E] AISC Manual table for shear-tab capacity (Table 10-9).
  5. [E] Sketch a typical bolted double-angle shear connection.
  6. [M] Design shear tab for Vu = 50 k, W18x35 to W14x90 column.
  7. [M] 2L4x3-1/2x1/4 double-angle, 3 rows of 3/4 A325-N. Compute φRn per Table 10-1.
  8. [M] Coped-beam W21x62 (2 in. top flange cope). Block-shear at the cope.
  9. [M] End-plate shear conn 5/16 A36, 3 bolts per row, 2 rows. Size plate.
  10. [M] Shear-tab eccentricity: 3/8 tab, 4 bolts at 3 in. pitch. Compute eccentric moment on bolts.
  11. [H] Design complete double-angle shear conn for Vu = 95 k, W24x55 to W14x120 column flange.
  12. [H] Extended shear-tab (>3-bolt rows), Vu = 80 k, including stability check (§10-9).
  13. [H] All-bolted beam-to-girder with coped top flange: include web-tear-out and LTB at cope.
  14. [H] Single-plate snug-tight bolts: justify why slip-critical not required for simple shear.
  15. [H] Rotational capacity at 0.03 rad drift: confirm rotational ductility per Manual Part 10 commentary.
Structured Clues
  • Three limit states for a shear tab: bolt shear, plate bearing/tearout, weld.
  • Coped beams require a separate flexural-rupture and block-shear check at the cope.
  • Use AISC Tables 10-1 through 10-12 for prequalified capacities.
Code References
  • AISC 360-22 §J3, J4
  • AISC Manual Part 10

Quiz

1. Which AISC 360-22 chapter primarily governs shear connections?
2. In LRFD, the basic design inequality is:

Common Student Mistakes

  • Mixing ASD and LRFD load combinations in the same problem.
  • Using nominal strength Rn instead of design strength φRn.
  • Forgetting to check every limit state listed in the AISC chapter.

"Professor Explains" Script

Today we're talking about shear connections. Think of this topic as one step in the LRFD workflow: identify the demand, identify the limit states from the relevant AISC chapter, then check that φ·Rn is at least equal to Ru. We'll walk through the failure modes, the equations, and a worked example. Pay close attention to where the resistance factor changes — that's where students lose points on exams.