On stress distribution of spot–welded box beams with a longitudinal partition subjected to torsion

Box members formed by spot welding two thin–walled members of hat section are widely employed in motor vehicle frame structures. In particular, the members subjected to large bending loads are reinforced by sandwiching a longitudinal partition between the two hat members and spot welding to connect. This paper explains that although the partition increases the bending strength, it tends to increase the stress in the nugget end and to reduce the fatigue strength.