Simplified Pushover-Based Vulnerability Analysis of Traditional Italian RC precast structures

Vulnerability curves of traditional Italian reinforced concrete (RC) precast structures are evaluated in this paper through the Simplified Pushover-Based Earthquake Loss Assessment method (SP-BELA) proposed in Borzi et al. (2008). Although the prefabrication of RC members in Italy is widely spread, its application has been targeted almost exclusively to industrial buildings, probably because of the speed in construction and the relatively low costs. In the case of residential buildings or several multi-storey structures, other materials and techniques are usually preferred. The main characteristics of the aforementioned RC precast structures are not always consistent with seismic criteria (e.g. monolithic columns fixed at the base and pin-ended beams, absence of seismic rigid frames, shear-resisting connections). In particular, the connections are one of the weak points in terms of local resistance capacity and global seismic response (fib, 2003; Calvi et al., 2006). Within the procedure adopted and described in this paper, four structural typologies are defined as representative of the majority of the current Italian production and used to randomly generate a population of buildings. The structural behaviour of this population is evaluated through simplified pushover analysis. The generation of vulnerability curves is based on displacement capacity limits of the structures and on the displacement demand. The input motion severity is described through the peak ground acceleration (PGA), as it is a parameter commonly used for the seismic zonation in the modern seismic design codes