Use this rectangular weld group stress calculator to estimate weld stresses in a closed rectangular fillet weld group subject to direct shear loads and an in-plane torsional moment about the weld group centroid.
This calculator estimates the maximum resultant shear stress in a closed rectangular weld group. It combines direct shear stress from applied horizontal and vertical loads with torsional shear stress caused by a moment acting about the weld group centroid.
The calculator provides:
This calculator is intended for a closed four-sided rectangular weld group. It should not be used for C-shaped, L-shaped or open weld groups.
Total weld length:
Effective throat thickness:
Total throat area:
Unit-line polar moment:
Throat polar moment:
Direct shear stresses:
Torsional shear components at a point:
Resultant weld stress:
| Symbol | Description | Units |
|---|---|---|
| b | Weld group width | mm |
| d | Weld group depth | mm |
| h | Fillet weld size | mm |
| a | Effective throat thickness | mm |
| Vx | Horizontal shear load | N |
| Vy | Vertical shear load | N |
| T | Torsional moment about weld group centroid | Nmm |
| A | Total effective throat area | mm² |
| J | Unit-line polar moment | mm³ |
| Ja | Throat polar moment | mm&sup4; |
| τr | Resultant weld shear stress | N/mm² |
Enter the weld group dimensions and loads, then click calculate.
| Result | Meaning |
|---|---|
| Total throat area | The effective weld throat area resisting direct shear load. |
| Direct shear stress | The average shear stress caused by Vx and Vy. |
| Torsional shear stress | The additional shear stress caused by moment T acting about the weld group centroid. |
| Maximum resultant weld stress | The largest combined weld stress calculated at the four weld group corners. |
| Design allowable stress | The allowable weld shear stress divided by the selected safety factor. |
| Utilisation | The maximum resultant stress divided by the design allowable stress. A value below 100% passes this simplified check. |
This calculator is for a closed rectangular weld group subject to direct shear and an in-plane torsional moment about the weld group centroid. It is a simplified preliminary calculation.
| This Calculator Includes | This Calculator Does Not Include |
|---|---|
| Direct shear from Vx and Vy | Open C-shaped, L-shaped or parallel-line weld groups |
| Torsional moment about the centroid | Out-of-plane bending moment checks |
| Corner resultant stress calculation | Fatigue, cyclic loading or fracture checks |
| Utilisation and pass/fail check | Parent metal tearing or plate failure checks |
| Closed rectangular weld group behaviour | Code-specific interaction equations or full Eurocode/AISC compliance |
This calculator first calculates the weld group throat area and polar moment. It then calculates direct shear stress from the applied shear loads and torsional shear stress from the applied moment.
The resultant stress is evaluated at the four corners of the rectangular weld group. The largest resultant value is used for the utilisation check.
For weld group properties only, use the Rectangular Weld Group Properties Calculator.
For a simple direct shear fillet weld calculation, use the Fillet Weld Strength & Size Calculator.
For further weld strength formulae and weld group properties, see the RoyMech reference page: Weld Strength Formulae and Weld Group Properties.
It calculates direct shear stress, torsional shear stress and maximum resultant weld stress for a closed rectangular weld group.
Yes, if the eccentric load can be converted into a torsional moment about the weld group centroid. The moment can be entered as T in Nmm.
For a load acting at an eccentric distance from the weld group centroid, the torsional moment may be estimated as:
where P is the applied load and e is the eccentricity from the weld group centroid.
No. This calculator is intended for preliminary engineering checks. Final weld design should be checked against the relevant design standard, material properties, weld procedure and inspection requirements.
No. This calculator assumes a closed rectangular weld group. Open or irregular weld groups require different centroid and polar moment calculations.