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Bolt & Connection Parameters

Bolt
pcs
Total bolts in connection
kN
Design value (factored)
Plate (governing for bearing)
mm
Thinnest plate in joint
mm
Min = 1.2 d₀
mm
Min = 1.2 d₀
mm
Min = 2.2 d₀
mm
Min = 2.4 d₀

Results

Enter values
Shear resistance Fv,Rd per bolt
Bearing resistance Fb,Rd per bolt
Governing FRd per bolt
Total resistance n × FRd
Applied VEd
Utilisation η
Reserve capacity
Bolt area used
Edge distance e₁ < 1.2 d₀ — minimum not satisfied (EC3 Table 3.3).
Edge distance e₂ < 1.2 d₀ — minimum not satisfied.
Spacing p₁ < 2.2 d₀ — minimum not satisfied.
Spacing p₂ < 2.4 d₀ — minimum not satisfied.
Utilisation > 80% — consider more or larger bolts.
Shear governs — consider higher bolt grade to improve resistance.
Bearing governs — consider increasing edge distance or plate thickness.

Connection Diagram

Bolt Data Reference

Size d (mm) d₀ (mm) A shank (mm²) As thread (mm²) Min e₁ Min e₂ Min p₁ Min p₂

Calculation Method — EC3 §3.6

Shear resistance per bolt

Fv,Rd = αv · fub · A / γM2

  • αv = 0.6 for grades 4.6, 5.6, 6.8, 8.8
  • αv = 0.5 for grades 10.9, 12.9
  • A = As (thread) or A (shank) depending on shear plane location
  • γM2 = 1.25

Bearing resistance per bolt

Fb,Rd = k₁ · αb · fu · d · t / γM2

  • k₁ = min(2.8e₂/d₀ − 1.7, 1.4p₂/d₀ − 1.7, 2.5)
  • αb = min(e₁/3d₀, p₁/3d₀ − ¼, fub/fu, 1.0)
  • fu = ultimate strength of plate material

Spacing limits (EC3 Table 3.3)

  • e₁ ≥ 1.2 d₀ (min) / ≤ 4t + 40 mm (max)
  • e₂ ≥ 1.2 d₀ (min) / ≤ 4t + 40 mm (max)
  • p₁ ≥ 2.2 d₀ (min) / ≤ min(14t, 200 mm) (max)
  • p₂ ≥ 2.4 d₀ (min) / ≤ min(14t, 200 mm) (max)

Connection resistance

Governing resistance per bolt: