A preliminary assessment of slenderness and overstrength homogeneity criteria used in the design of concentrically braced steel frames in moderate seismicity

Abstract

Concentrically braced frames (CBF) represent a very effective structural form against horizontal loading. They provide high lateral resistance at the same time limiting lateral displacements. Thanks to their simpler connection details and smaller cross sections, they are economic alternatives to the costly moment resisting frames. Nevertheless, concerning the seismic design, current Eurocode 8 provisions require a quite high level of complexity for the dissipative design of CBF structures. The global aim of this research is to find an optimal balance between safety and economy for the design of CBF structures, located in low-to-moderate seismic regions. New design rules will be proposed which will have less stringent local ductility and structural homogeneity requirements than current medium ductility class (DCM), and provide necessary safety level limiting the complexity and costs associated with anti-seismic design. This paper presents the results of the preliminary numerical analysis that has been realized thanks to the research fund received from European commission with the contract MEAKADO RFSR-CT-2013-00022.