Sustainable retrofitting solutions for precast concrete residential buildings: Architectural and structural aspects

In the present context, a large part of the Romanian urban population, like that of Eastern Europe, lives in collective residential buildings with concrete structure made of large prefabricated concrete panels. Most of these buildings are over 30 years old, and the materials used for thermal insulation are already outdated. Starting from the representative typologies of existing buildings, the context when they were built, their evolution in time, and their current and actual problems, the paper presents some directions, modalities, intervention methods and their implementation for rehabilitation. The paper presents architectural solutions for redesigning the interior spaces of large panel prefabricated concrete buildings by coupling apartments on horizontal or vertical direction and also the structural interventions to be considered. 3D numerical analyses are conducted on these buildings, both on initial and retrofitted structures. The study is focused on using steel solutions for strengthening the affected elements, due to their inherent advantages such as clean intervention, reversibility, resistance and adaptability.