Study of continuity plates in steel moment connections

Abstract

            The use of continuity plates has been recommended in all steel moment connections by the AISC-LRFD design codes after the 1994 Northridge earthquake. This is because the preliminary study right after the earthquake showed that continuity plates significantly reduce the high stress concentration in the center of beam flanges. Based on this study; however, it shows that effectiveness in reducing the high stress concentration in the beam flanges of continuity plates rapidly reduces with the increasing of the column flange thickness. The stress concentration in the beam flange did not reduce with the presence of the continuity plates as previous thought with the heavy column size. Therefore this study recommended that continuity plates are not necessary for the column-to-beam thickness ratio (tcf/tbf) over 5.0.