IMPLEMENTATION OF DAMPING TOWERS AS A SEISMIC RETROFITTING STRATEGY FOR AN EXISTING HOSPITAL BUILDING

Over the years, enforcement and continuous improvement of seismic regulations have been evidenced worldwide. In Italy, after major seismic events such as the Molise and L’Aquila earthquakes, the seismic design was implemented, and it became mandatory from July 1st, 2009 with NTC2008 code. Addressing seismic assessment in existing strategic structures, built before the 60’s, is becoming increasingly necessary and evident since the seismic risk that characterizes this type of structures is very high. Within this framework, this paper focuses on the seismic retrofitting of the most vulnerable building of “Ospedale Edoardo Agnelli,” a hospital complex located in Torino, Italy. The retrofitting strategy consists of a damping tower system, whose prime is to increase the structural performance, minimize occupant disruption and indirect costs, guarantee the immediate operation of the building even during high-intensity earthquakes, and elongate the building's structural service life. To demonstrate the structural efficiency of the retrofitting strategy considered, a structural model is defined based on the available documentation of the building and extension of the investigations carried out recently and over time, defining a level of knowledge with a value equal to two. The corresponding three-dimensional model is done through the MIDAS Gen Software, in which regarding the Italian building code NTC2018, two different types of analysis are performed: linear dynamic analysis and nonlinear dynamic analysis, respectively. The results obtained were compared in terms of the safety index value of the global behavior of the structure, concluding that the damping tower system proves to be an efficient intervention for the existing building with a safety index value higher than 0.80.