Structural performance of the historic and modern buildings of the University of L’Aquila during the seismic events of April 2009

The University of L'Aquila plays a central role in the life of the city of L'Aquila from both cultural and economic perspectives. The buildings of the University, located mainly in three zones of the town, constitute a significant sampling of the different architecture typologies coexisting in the area, including examples of traditional masonry buildings together with modern constructions of architectural value. Ranging from the historical buildings Palazzo Carli, Palazzo Camponeschi and Palazzo Porcinari, located in the old town center, to the reinforced concrete buildings dating from the mid-90s, the buildings exhibit many different structural properties resulting from a variety of construction techniques, materials, and erection dates. The present paper focuses its attention on understanding the behavior of these buildings during the earthquake events that repeatedly struck the region of L'Aquila during the seismic sequence of April 2009. The purpose of the paper is to identify the probable causes of structural failure, paying particular attention to the recurrent collapse mechanisms associated with the different structural types. The paper contains a report of visual inspections conducted for the detection and assessment of damage, and presents an overview of the activities conducted by the Unità Operativa di Ingegneria Sismica, a work group within the Dipartimento di Ingegneria delle Strutture, delle Acque e del Terreno (DISAT-UOIS) of the University of L'Aquila. Preliminary numerical results concerning the seismic behavior of a few selected buildings are also presented, as obtained from three-dimensional finite element models simulating their structural response to different accelerograms registered in the area.