Apart from vertical bending, lateral loads will be introduced in this area. It is therefore important to avoid welding at the edge of the flanges, since these are high-stress areas.  

To reduce the stiffness gradient between the hanger bracket and the lower flange, it is beneficial to weld the bracket to an attachment plate. The plate must have sufficient thickness, and the welds between the plate and the flange must be positioned at least 20 mm from the edge of the flange. Variable flange width can be introduced to increase the bending moment capacity and the area available for attaching the hanger brackets. To further improve the fatigue life, the hanger bracket attachment can be designed as a bolted joint, as in the illustration below.

Any web stiffeners used to manage the local vertical shear loads in this region should be positioned in line with the loading direction from the hanger brackets. Placing the stiffener at a distance from the hanger bracket will introduce an additional bending of the lower flange and reduce the fatigue life significantly.

Placing the web stiffener at a distance from the hanger bracket introduces additional bending to the lower flange, which will rapidly reduce fatigue life. To improve the fatigue properties, any web stiffener in this region should be positioned directly in line with the hanger bracket. Introducing a wider flange increases the resistance to side bending and enables the welds to be placed at a distance from the critical area at the lower flange (2). To improve the fatigue life even further, a bolted joint could be introduced (2).