Design and modelling strategy for cold-formed steel exoskeletons for the seismic-energy retrofit of reinforced concrete structures

Recent seismic events have highlighted the vulnerability of reinforced concrete (RC) buildings constructed before the enforcement of seismic design codes. This study is focused on a cold-formed steel exoskeletons, known as the Resisto 5.9 Tube system, used to enhance both seismic and thermal performance of existing structures. The main focus is the application of a simplified design and modelling strategy to elementary reinforced concrete structures with different heights. The design strategy is aimed to optimize the elements of Resisto 5.9 Tube according to the specific building under investigation. The modelling strategy is developed to reduce the computational effort when implementing the reinforcement system in structural software without negatively affecting the reliability of the results.