Displacement-Based Simplified Seismic Loss Assessment of Italian Precast Buildings

1

ABSTRACT

Economic losses associated with the structural and non-structural damage occurring after an earthquake are of particular importance in the case of industrial buildings due to the consequences of such losses on the local economy and employment level. The seismic sequences that hit the industrial area of Emilia-Romagna region of Italy in 2012 represent an emblematic example. In this earthquake event, major damage on poorly performing precast structures was recorded: many buildings were severely damaged and experienced partial or full collapse. The level of the recorded damage was related to a design lacking modern seismic detailing and to a non-up-to-date evaluation of the seismic hazard: in fact, several industrial buildings, typically one storey precast reinforced concrete (RC) structures, were designed to transfer horizontal loads (i.e. between roof elements and supporting beam or main girder and supporting columns) through either friction or under-designed mechanical connections. The aim of this paper is to provide insights on the evaluation of direct losses in the case of precast RC structures typical of the Italian industrial sector, particularly for buildings built before the enforcement of modern seismic codes. A simplified displacement-based seismic loss assessment procedure is proposed and applied to a selected case study and comparisons are made with the results obtained from non-linear time history analyses on simplified (i.e. single column models) and complete three-dimensional models. Retrofit solutions are proposed and their influence on the collapse probability of the structural elements and on the economic losses is evaluated.

KEYWORDS:

• Displacement-based assessment
• seismic losses
• precast structures
• precast connections

Acknowledgments

The contribution of Eng. M. Bassetti and Eng. M.E. Bressanelli in setting up the OpenSees and Matlab model is gratefully acknowledged. The study presented in this article was developed within the activities of the ReLUIS-DPC 2014-2018 research program. Opinions and conclusions do not necessarily reflect those of the funding entity and of the people acknowledged.

Additional information

Funding

This work was supported by the Reluis (Italian Laboratories University Network of Seismic Engineering).