Strength of Steel Frames Using Partial Composite Girders

Abstract

This study investigates the behavior of composite concretesteel girders and evaluates their role in wind bents of unbraced Type 2 steel building frames. A nonlinear inelastic computer program is developed to perform a limit state analysis of partial composite girders and provide the nonlinear bending characteristics needed for collapse analysis of frames. The results indicate that composite girders do not increase frame strength compared to equivalent designs using noncomposite girders. It is concluded that the current design method used for Type 2 design with composite girders in a wind bent will result in frames with an adequate, though not excessive, level of safety for typical frames less than 10 stories in height.