In the master's thesis, the design of steel frames is presented in accordance with the proposal of the second generation EC8 standard. The analysis focuses on a practical example of a 5-story steel structure featuring two frames with eccentric braces in the X-direction and four frames with concentric braces in the Y-direction. The seismic action is defined according to the EC8 proposal, which allows the application of two methods for determining spectral ground acceleration. The findings indicate that the curves representing the relationship between spectral accelerations and the structure's natural period are not comparable, as they exhibit significantly different trends. These trends resemble the average curve of the uniform seismic hazard spectrum and may be on the hazardous side. The calculation procedure for frames is outlined for ductility classes DC3 and DC2. The computational analysis is performed using Scia Engineer. The design process for frame elements with eccentric braces for ductility class DC2 follows closely the current standard. In contrast, the process for ductility class DC3 relies on the strength of the seismic element’s performance. Portions of the standard addressing frames with concentric braces have been supplemented and adapted for both ductility classes. For all defined frames, a pushover analysis is executed using SAP2000. During the design earthquake, frames with concentric braces remain in the elastic range due to steel’s high deformation capacity in tension, while frames with eccentric braces behave predictably, allowing the primary load-bearing system to be re-established upon replacement.
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