Past earthquakes have shown that seismic events may incur large economic losses in buildings. FEMA P-58 provides engineers a practical tool for the performance seismic assessment of buildings. In this article, FEMA P-58 is applied to a typical Italian pre-1970 reinforced concrete frame building, characterized by plain rebars as steel reinforcement and masonry infills and partitions. Given that suitable tools for these buildings are missing in FEMA P-58, in the first part of the article, specific fragility curves and loss functions for the main structural and non-structural components of the building type under consideration are proposed. In the second part, building performance is evaluated following a time-based assessment approach. Expected economic losses in form of repair costs are then derived. Finally, results are compared with those from past applications to old RC frame buildings.

Monetary losses induced by earthquakes in Reinforced Concrete (RC) buildings are mainly due to damage to non-structural elements (infills, partitions, finishes, etc.). In this study, alternative retrofit strategies for reducing monetary losses in RC frame buildings are examined. They include local strengthening of infills (and partitions) and seismic isolation. The Expected Annual Loss (EAL) of a number of RC frame buildings, pre- and post-rehabilitation, is evaluated, following the time-based assessment approach proposed in the FEMA P-58 guidelines. The breakeven time of each retrofit intervention is then computed, considering the initial cost of the intervention and the expected benefit in terms of EAL reduction.

A displacement-based design (DBD) procedure for buildings equipped with different seismic isolation systems is proposed. It has been derived from the Direct Dispaced-Based Design (DDBD) method recently developed by Priestley et al. [2007] Priestley, M. J. N. , Calvi, G. M. and Kowalsky, M. J. 2007. Displacement-Based Seismic Design of Structures, Pavia, , Italy: IUSS Press. [Google Scholar] . The key aspect of the proposed procedure is the definition of a target displacement profile for the structure. It is assigned by the designer to achieve given performance levels, expressed in terms of maximum displacement of the isolation system and maximum interstory drift. The proposed design procedure has been developed for four different idealized force-displacement relationships, which can describe the cyclic response of a wide variety of isolation systems, including: (i) Lead-Rubber Bearings (LRB); (ii) High-Damping Rubber Bearings (HDRB); (iii) Friction Pendulum Systems (FPS); and (iv) Combinations of lubricated Flat Sliding Bearings (FSB) with different re-centering and/or energy dissipating auxiliary devices. In this article, the background and implementation of the design procedure is presented first. It is followed by the results of validation studies based on nonlinear time-history analyses on different design configurations of base isolated buildings.