Eurocode 3 Weld Strength

Section 4 of the standard EN 1993-1-8:2005 Design of joints is implemented to verify the structure stability of each structural member (weld).

Eurocode3 Part 1-8

To add the standard execute Standard - Eurocode3 Welds (EN 1993-1-8) from the main menu. Alternatively, use the Standard context menu:


By default all welds that match the following criteria are included into the selection but can be changed by pressing .

Weld is included in calculations if it is:

1. Straight with the tolerance of 3 degrees;

2. Double-symmetric - weld is formed by 2 planes that are perpendicular to each other with the tolerance of 5 degrees;

Preview weld elements that are not verified press Button_preview_all_not_supported_welds.

Preview selected weld elements by pressing Button_display_selected.

If welds are not recognized press Button_weld to run the Weld Finder tool.

Note: In results only welded parts are calculated. The rest of the parts will not contain results.

Press to set a Correlation factor (Beta_w):

Beta_w factor is obtained from the Table 4.1, section and depends on the material type:


If Include geometrical check option is ON, an extra check with minimum/maximum weld length and throat thickness will be added to the standard:


Press to set formulas for the check:


It is possible to select 3 predefined types of bounds and custom:


Remove 'Tip:' and set an 'input value in model units' to make the formula correct.

Result check will contain all included parameters and overall parameter that defines if all bounds pass:


LimitsOK parameter returns 0 if all limits are OK and 12345678 otherwise.

Use Yield/Tensile from - option which defines the Yield Stress/Tensile Strength to use in calculations (from Element/Material or from Weld Finder). By default minimum value of Yield.

Stress/Tensile Strength is calculated using all weld elements, user can override them in Weld Finder.

Gamma_M2 - material resistance factor for plated structures is a constant value (=1.25) and used in calculations to check a base material strength.

Formulas use Yield Stress and Tensile Strength from materials. It is important to set these values for each material. The amount of materials with zero values are displayed:


If count > 0 then press Button_materials to edit parameters:

Checks are created automatically and divided into few parts:


T|| = shear design stress (in plane of the throat) parallel to the axis of the weld (equal to X direction in the check);

σ⊥= normal design stress perpendicular to the throat (equal to Y direction of the check);

T⊥ = shear design stress (in plane of the throat) perpendicular to the axis of the weld (equal to XY direction of the check);

Example of the check for point T1:


Calculation Method defines the way of results calculations/presentation - per weld part or per element. They are described in Force Summation tool.