Gusset Plate Connections in Concentrically Braced Steel Structures

Built-up box section members are becoming a popular alternative to steel open section members, particularly due to lack of production of large H-sections in steel profile factories. In the former braced frames with H-shaped columns, using a gusset plate was the most convenient way to connect the bracing to the column. This practice is now continued to be used in connection of brace to the box face. In this case, the gusset plate is welded at the center of the connecting flange, so the axial load is transferred directly to the web of the member. But the seismic configuration is completely different for built-up box columns because in this case the axial load must be carried into the two remote webs of the built-up box section member. A comprehensive investigation on seismic performance of columns with box sections is provided in this paper. The obtained results from finite element analysis of 9 different cases are compared with a similar column stiffened by through plate. The advantages and disadvantages of study connections are provided by a detailed parametric study.