The effect of using fillet in reducing weld stress concentration of saddle-like connections

Saddle-like connections are one of the common semi-rigid beam-to-column connections in typical steel structures of the country, which have attracted a great deal of attention in construction across various regions over a long period of time. The discrepancy between distribution of actual stress and distribution of design stress alongside stress concentration in the corner of angles is among the reasons of vulnerability of this type of connection. In this paper, a typical saddle-like connection was considered as reference, and then by adding strut to the connection, stress concentration on the corners decreased, while the ductility capacity of the connection increased. Thereafter, two other forms of connection, inspired by the reference connection, were modeled by CATIA software one by adding fillet on both sides and along upper and lower directions and the other by adding fillet on both sides of the lower part of beam to column intersection. The proposed forms underwent increasing cyclic loading, and by analyzing them through Ansys finite element software, it was found that changes in the type of connection through adding fillet was more effective than the strutted connection for enhancing strength and prevented stress concentration.

Keywords:

saddle-like connection , stress concentration , fillet , connection strength , IPB beam