Use of Energy-Dissipative Rocking Steel Columns for Seismic Rehabilitation of Existing Buildings

Many strategic buildings are highly susceptible to seismic activity even they should maintain full functionality immediately after severe earthquakes due to their crucial role in emergency management. Additionally, they should remain operational even during seismic retrofitting efforts, leading to the development of retrofit solutions characterized by rapid, minimally disruptive, and reversible interventions. This study introduces and applies a Continuous Energy-Dissipative Steel Column (CEDC) system for the seismic retrofit of an existing steel-reinforced concrete hospital building. The lateral stiffness and strength of the CEDC system are determined based on the geometric and mechanical properties of the steel strip dampers. The hysteretic behavior under cyclic loading is defined using a simplified numerical model, and its effectiveness is validated by comparing results with full-scale experimental data from existing literature. The retrofitting plan's main design considerations are thoroughly described. Nonlinear time-history analyses under various earthquake-strong ground motion scenarios demonstrate the efficacy of the proposed retrofitting system. The results indicate that the CEDC system effectively controls the deformation pattern and significantly reduces structural damage during major earthquakes.