Design Procedure for Eccentrically Braced Steel Frames

This paper provides the results of the application of the Theory of Plastic Mechanism Control carried out in the α − θ plane with reference to the Eccentrically Braced Steel Frames (EBFs) with horizontal links. EB-Frames are an excellent structural solution characterized by the high lateral stiffness and the good ductility referred to the seismic links. The TPMC procedure allow to design the structures capable of failure according to a collapse mechanism of global type. Recently, this procedure has been revised by modifying the kinematic design parameter. In fact, in the previous version, the design parameter was the top sway displacement, while, in this work, it is represented by the plastic rotation of the dissipative elements. This modification offers the achievement of the design objective with more economically advantageous solutions. To evaluate the accuracy of this approach, numerical applications have been developed on multi-storey EBFs in the horizontal link configuration according to TPMC. Then non-linear static analysis and incremental dynamic analysis have been performed. The results confirm the achievement of the main design goal, i.e., the collapse mechanisms of the investigated structures are the global type by avoiding the undesired failure mechanisms as the soft storey mechanism.