Free Tool · EN 1993-1-8 §4.5.3.2 · Welded Moment Connection · Beam-to-Column

Welded Moment Connection

Fully-welded I-beam to I-column moment connection per EN 1993-1-8 §4.5.3.2. Directional method for flange welds, panel zone shear, column flange transverse bending, and web checks — all in one tool.

EN DE FR ES IT NL PL SV DA
Presets:
Beam Section
Min 3mm, max 0.7×t_min per §4.5.2.
Column Section
Min 3mm, max 0.7×t_min per §4.5.2.
Material & Forces
γM2 = 1.25 per EN 1993-1-8 §6.1(1). γM0 = 1.0 for most NL/DE/BE annexes.
Resistance Checks
FAIL — one or more checks exceeded
Governing check
Utilization
Stiffeners required
Connection Schematic
M V N F_f F_f z = 388 mm STIFF
Utilization Chart
<80% — Green 80–100% — Amber >100% — Red
Resistance Checks
Check Utilization η Status
Export calculation report
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FAQ
When does the column need stiffeners?
Stiffeners are required when column web compression (Eq 6.10), web tension (Eq 6.11), or panel zone shear (Eq 6.7) exceed ~85% utilization, or when the column flange transverse bending check fails. The tool flags "Stiffeners required" when any check exceeds this threshold. For heavy industrial frames or high-moment connections, diagonal or transverse stiffeners per §6.2.6 are typically provided.
What is the directional method for weld design?
EN 1993-1-8 §4.5.3.2 uses the directional method where weld stresses are resolved at the throat: σ⊥ = F_perp / (2·a·l), τ∥ = F_parallel / (2·a·l). Two conditions must be satisfied: √(σ⊥² + 3(τ⊥² + τ∥²)) ≤ fu/(β_w·γM2) and σ⊥ ≤ 0.9·fu/γM2. The β_w correlation factor (Table 4.1) accounts for the ratio of the weld metal to the base metal tensile strength.
How is the weld group lever arm z defined?
z = h_b − tf_b (beam depth minus flange thickness). For a symmetrical welded moment connection, the tension in the bottom flange and compression in the top flange produce a couple with lever arm z. This couples directly with M_Ed: F_f = M_Ed / z.
What is β in the panel zone shear check?
β = 1 + M_Ed / (V_Ed · z) for a rigid end-plate moment connection, per EN 1993-1-8 Eq 6.7. When V_Ed = 0 or z = 0, β = 1.0. The factor accounts for the additional shear from the unbalanced moment transmitted through the panel zone from the beam end.
Can this tool handle combined axial + bending?
Yes. Enter N_Ed alongside M_Ed and V_Ed. Axial force adds/subtracts from the flange force: F_f = M_Ed/z ± N_Ed/2. Combined N+M checks for the column itself should use the beam-column interaction calculator.
Does this tool cover welded column splices?
No — this tool is for beam-to-column moment connections. Column splices involve different geometry (column continuity plate, different stiffener arrangement) and should use a separate splice design tool or the intake pipeline for full fabrication output.