Seismic performance assessment of an existing RC building in Rozaje according to EN 1998-3

Abstract

Given that Montenegro is located in a region with a high seismic hazard, assessing the seismic performance and retrofitting of existing buildings is crucial for reducing seismic risk. This presents a significant challenge in modern construction, as most existing buildings were designed according to outdated regulations, making them non-compliant with contemporary seismic standards and necessitating structural retrofitting.

This research focuses on the seismic assessment of an existing reinforced concrete (RC) frame building in Rožaje, with the aim of verifying the compliance with the significant damage limit state as defined by the European standard EN 1998-3.

The analysis of the existing building, modeled in the ETABS software package, was carried out using non-linear static Pushover analysis. Material and structural nonlinearity characteristics were defined, along with the plastic mechanism and nonlinear loading, all in accordance with EN 1998-3. The Pushover analysis was conducted in 50 steps, during which the predefined plastic mechanism demonstrated the formation of plastic hinges within the structure.

The results indicated that while the building does not meet the significant damage limit state, its deformation capacities remain within acceptable limits, whereas shear capacity is exceeded. Consequently, it was concluded that shear retrofitting of specific structural elements (beams and columns) is necessary to meet the EN 1998-3 requirements. FRP (Fiber Reinforced Polymer) materials were identified as the optimal solution for retrofitting.

This study provides valuable insights into the seismic performance of similar structures in Rožaje and other Montenegrin cities, offering a basis for improving seismic resilience in line with modern regulations.