SEISMIC RETROFIT OF RC STRUCTURES WITH DISSIPATIVE BRACES, DESIGN AND SUSTAINABILITY

Existing reinforced concrete frame buildings with non-ductile detailing suffered severe damage and caused loss of life during earthquakes. Different rehabilitation systems have been developed to upgrade the seismic performance of this kind of structures. The research discussed in this paper, deals with the seismic protection of frame structures and a displacement-based procedure to design dissipative bracing for the seismic protection of frame structures is proposed and some applications are discussed. A two-fold performance objective is considered to protect the structure against collapse and non-structural damage (and consequently limiting retrofitting costs in case of a seismic event) by limiting global displacements and interstorey drifts. The described procedure has been applied to retrofit an existing building complex in the province of L'Aquila (Italy). Different criteria have been adopted for each single building of the complex; the solution with dissipative braces has been compared with a traditional one adopting r.c. walls. For each solution technical and economic evaluations were performed, results have been discussed and compared.