Simple welds LRFD (AISC)

The load resistance of welds subjected to simple loading – tension/compression, shear, and bending – is investigated.

Sub-code: LRFD

Type of connection: simple welded connections

Unit system: Metric

Designed acc. to: AISC 360-16

Investigated: Welds

Plate Materials: Plate and column – ASTM A572 – Gr. 50

Welds: Leg size = 3 mm, electrode E70XX

Applied forces:

Simple welded connections are loaded by tension, compression, bending moment or shear to be utilized at 100 %.


Simple welded connections of a plate to a beam are designed so that welds will fail first. The plate is loaded by only one component at a time – tension, compression, bending or shear. The joint is loaded for weld to be utilized at 100 % and the load is compared to the weld resistance according to AISC 360-16.

Manual calculation

In the case of bending, both elastic and plastic stress distribution were calculated. Usually, the more conservative elastic stress distribution is assumed although tensile strength of welds is used in formulas.

a) elastic stress distributionb) plastic stress distribution

Base metal strength does not have to be evaluated in case of use of matching electrodes but it is shown here for verification.

Manual check is performed according to AISC 360-16 – J.2.4.


Weld strength without base metal check

Weld strength with base metal check

The results of both IDEA StatiCa Connection design and computation according to AISC Design examples gives nearly identical values in case of simple welds both with and without base metal check. IDEA provides slightly conservative results (at 98 %) for tension, compression and shear loading. Weld subjected to bending shows a behavior between elastic and plastic stress distribution, being closer to the plastic distribution.