Performance assessment of X-CBF designed according to an improved (EC8-based) approach

The paper analyses the seismic performance of steel structures with X Concentric Braced Frames (X-CBF) designed both according to Eurocode 8 and according to a new design approach proposed by the authors in previous works. In detail, for validating the proposed design methodology, non-linear dynamic analyses have been carried out by using the computer code CLAP, with reference to several buildings characterized by different numbers of stories, numbers of braced bents in plan and by different bay spans. The results of the numerical analyses, expressed in terms of several parameters of structural performances, show that the proposed approach leads to: (i) reduce the unnecessary global overstrength due to the application of EC8 design rules; (ii) obtain an optimized structural design; (iii) ensure a good local and global ductility of braces under cyclic actions; (iv) have a greater “flexibility” in the design process.