Retrofitting technique effectiveness and seismic performance of multi-rise RC buildings: A case study

This study aims to determine the effectiveness of a retrofitting technique based on the seismic performance analysis results comparison between two inactive multi-storey reinforced concrete (RC) buildings for a long period. Their seismic performance is determined according to the latest Turkish Building Earthquake Code (TBEC-2018) recommendations. The main difference between the examined buildings is the reinforcement (retrofit) technique applied to one of them with additional new shear walls. The whole process was demonstrated with a code-based approach, and the results were compared after the performance evaluation. The structural system geometry, member dimensions and plan layout of the buildings are checked with the original design projects by making on-site measurements. The material properties of the buildings are determined by field studies and laboratory studies. Buildings are modelled with finite element software, and numerical simulations are performed to determine the seismic performance levels according to existing code. As a result of the analysis, the effectiveness of the retrofit approach was examined by comparing the structural behaviour and seismic performance levels of both buildings. The results showed the importance of some parameters that should be taken into account in the retrofitting process with the addition of new shear walls to RC structures. While the applied retrofit process increased the stiffness of the structure and decreased the displacements, the results indicated a failure with a shear-critical condition.