Starred angles supporting secondary trusses: Fid-Bau Portal

Starred angles supporting secondary trusses

Temple, Murray C. / Hon-Wa Mok, Kenneth

AbstractIn some large industrial buildings, it is common to span large areas by using primary trusses in one direction and secondary trusses in the other. The secondary trusses frame into the vertical web members in the primary truss. Because of their symmetrical cross-section and the ease with which the connections can be made, starred angles are frequently used as the vertical web members in primary trusses. These starred angles are usually designed as axially loaded members, but the open nature of the cross-section and the fact that the secondary truss frames into one of the angles have raised some doubts about the loading assumption.As a result of this concern, an experimental research program was undertaken to investigate the behavior and strength of starred angles supporting secondary trusses. The results obtained indicate that these starred-angle compression members are not concentrically loaded as the stress distribution across the angles varies greatly. It was found that, if the slenderness ratio is modified, the load-carrying capacity can be calculated in accordance with the requirements of the Canadian steel standard.