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Following recent earthquakes, precast buildings exhibited a strong seismic vulnerability related to the presence of closure external panels. The aim of this work is to simulate the seismic response of existing single-storey precast buildings in the case of explicit modelling of external panels. The considered case studies are precast buildings representative of the Italian building stock in the 1970s and 1990s, characterised by two different cladding systems, namely, masonry infills and reinforced concrete precast panels, respectively. The explicit modelling of infills and panels, typically introduced solely as participating masses, provided insights into their actual contribution on the global structural behavior. [ABSTRACT FROM AUTHOR]

Italian reinforced concrete precast industrial buildings featuring frictional beam-to-column connections suffered from severe losses following recent earthquakes. Despite the relevance of this topic, the current literature includes only few works investigating the seismic behaviour of these buildings, the influence of vertical records on their modelled dynamic response, as well as the sensitivity of their seismic fragility to the friction type implemented in-situ. The above considerations imparted momentum to this research. First, a sensitivity analysis was conducted considering both concrete-to-concrete and neoprene-to-concrete friction types, as well as the presence or absence of vertical records in the vulnerability analyses. Within a multiple-stripe analysis framework, a number of nonlinear dynamic analyses were carried out on two precast building models created in OpenSees and assumed to be located in three Italian cities subjected to different hazard levels. Fragility curves related to the limit states of Serviceability Preventing Damage and Life Safety were derived. Then, epistemic uncertainty in the friction type and the influence of vertical records on the fragility curve was treated by employing a logic tree framework, allowing for the derivation of weighted average fragility curves, one per city. While the latter are structure-specific and site-dependent, they may be considered as generic or typological fragility curves, for use by researchers or practitioners who are interested in carrying out a fragility analysis on a reinforced concrete precast industrial building but are not confident on the friction type implemented in-situ and the influence of vertical records for the site and structure at hand. [ABSTRACT FROM AUTHOR]

Seismic performance-based design approach is currently implemented in modern building codes. Design requirements and provisions ensure an adequate structural performance under different intensity levels of seismic action. However, the probability of attainment of a performance level is implicitly considered in the code design approach (provisions and requirements); for instance, the minimum requirements in concrete structures cannot be simply correlated to the probability of collapse of the building as well as to its overall structural response. The aim of this work is to assess the vulnerability with respect to the collapse limit state of industrial single-story RC precast buildings designed according to the current Italian seismic code. The comparison between the Italian code and the Eurocodes is provided throughout the paper. A parametric study is performed by investigating the safety against the collapse of 40 RC single-story precast structures. Multi-stripe analyses are performed by non-linear dynamic analyses at 10 intensity levels. The fragility of the structures is defined by means of the incremental N2 method, which has been demonstrated to be a suitable method for evaluating the collapse capacity of single-story precast buildings. The results demonstrate that the buildings are safe against the collapse mainly because of the structural overstrength with respect to seismic actions. The modelling assumptions are also validated in order to demonstrate the negligible influence of the cracking on the collapse as well as the importance of the geometrical nonlinearities for precast buildings. [ABSTRACT FROM AUTHOR]

In this study, industrial single-story RC precast buildings are investigated. Twenty-four case studies have been considered, in which the column height, the beam spans and the seismic hazard level are varied. The seismic design of the selected case studies is performed according to the Italian building code and additional technical documentation. Three-dimensional nonlinear models are defined to perform static and dynamic analyses for the seismic assessment of the selected case studies. Demand/capacity ratios in terms of the selected engineering demand parameters are computed for ten increasing values of the seismic input return period. [ABSTRACT FROM AUTHOR]

Old precast buildings are often characterized by poor detailing that may hamper the structural performance, particularly in the case of earthquakes. This is essentially related to: (i) a limited past knowledge of seismic design and behaviour, also reflected in past building codes; (ii) the evolution of seismic zonation of the Italian territory. The aim of this work is to assess the probabilistic seismic vulnerability with respect to the usability preventing damage and global collapse performance levels of four existing single-story precast buildings designed in accordance with past Italian building codes from 1960s to 1990s in three sites with increasing seismic hazard. [ABSTRACT FROM AUTHOR]