Permissible Parameter Ranges of Access Hole Geometries for WUF-W Connections

Abstract

The welded unreinforced flange-welded web (WUF-W) connection is one of seven prequalified connections for special moment frames (SMF) specified in AISC 358-10 (2010). Previous studies reported that the cyclic behavior of WUF-W connections was strongly affected by weld access hole geometry, and some WUF-W connections did not satisfy the requirements for SMF connections. For investigating in detail the effect of access hole configurations on the cyclic behavior of WUF-W connections, this study conducts three-dimensional nonlinear fmite element analyses. This study shows that the seismic behavior of WUF-W connections are strongly affected by two configuration parameters, access hole slope and length of flat portion. To satisfy the requirement for SMF connections, this study proposes a range of the access hole slope and length of flat portion for WUF-W connections considering different span-to-depth ratios, beam depths, and material types.