Reduced beam section (RBS) is one of the several connection types, which is economical and popular for use in new steel moment frame structures in seismic zone. To form RBS connection, some portion of the beam flanges at a short distance from column face is purposefully trimmed so that the yielding and plastic hinge occurs within this area of flanges. Use of RBS connection is found advantageous due to: a) the shear force in the panel zone is reduced; b) the force demand in column continuity

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... es i.e. stiffeners are reduced; and c) strong-columnweak-beam requirement is satisfied. Although, radius cut RBS is qualified by ANSI/AISC, FEMA codes, various flange cut shapes like constant, tapered, radius cut, drilled holes are possible to reduce the cross sectional area of beam flanges. The purpose of this study is to understand behavior of RBS beam-to-column moment connections for various flange cut geometries. This document represents nonlinear finite element analysis of the connection models performed using the computer program, ANSYS/Multiphysics