Usefulness of internal welds of nodes in hollow core profile truss bridges

Usefulness of internal welds of nodes in hollow core profile truss bridges

Phenomenological Aspects of Civil Engineering (PACE) - an International Congress
Volume 1 - Issue 1 - PACE-2021

Philippe Van Bogaert


Steel truss structures are a powerful and reliable type of bridge girders. The complex part of trusses are the nodes, especially if more than 4 members are converging. Such nodes require providing internal welds; inaccessible after completion, which may be forgotten during assembling. This study assesses whether all of the internal welds are indispensable. The latter is tested for a particular bridge, consisting of hollow core profiles, intersecting at the nodes. After determining the member forces, including bending moments, an alternative load path is indicated, which must occur if the internal welds are missing. According to the relevant code, weld stresses are determined by evenly distribution of forces. Formulas are given to determine the weld stresses. In ULS some of the welds require a small amount of strengthening if the internal welds are omitted. In addition fatigue resistance was determined. Although the fatigue damage increases in this particular case it is still acceptable. Certainly for this example internal node welds may be left out, although this does not necessarily apply to more complex node cases. Further steps for research are given.


Steel truss bridges, welding of nodes, weld stresses, alternative load path, truss node fatigue resistance.