ANALYSIS OF LOCAL MECHANISMS THROUGH FLOOR SPECTRA FOR THE PRESERVATION OF HISTORICAL MASONRIES. A CASE STUDY Mariateresa Guadagnuolo 1 , Marianna Aurilio 1 , Anna Tafuro 1 and Giuseppe Faella 1 1 Department of Architecture and Industrial Design University of Campania “Luigi Vanvitelli” {mariateresa.guadagnuolo, marianna.aurilio, anna.tafuro, giuseppe.faella}@unicampania.it Abstract Non-structural masonry elements represent a significant part of the masonry cultural heritage due to their historical and artistic value. A significant portion of the total losses in recent earthquakes worldwide has been attributed to damage to non-structural elements, that are often very dangerous for public safety. These elements, i.e. merlons, pinnacles, sundial, gable, often undergo out-of-plane failures also for low values of peak ground acceleration. The assessment of the safety of these elements requires a correct evaluation of the seismic demand, to be performed considering the amplification and filtering effects due to the underneath structure, since they are often placed on the upper storeys of the buildings. To that end, the floor spectra are a powerful tool for assessing the earthquake acceleration and displacement requirements on non-structural elements. This paper focuses specifically on the linear and nonlinear kinematic analysis of freestanding masonry elements, comparing the previous Italian Building Technical Code (2008) with that of in force. The out-of-plane overturning mechanism of the protruding portion of the façade of a small chapel is studied, in order to better identify the main parameters that influence the evaluation of seismic safety of such a type of non-structural elements. The seismic demand in acceleration and displacement is computed by floor spectra both through a simplified approach and by using all modes assumed to be significant in the activation the out-of-plane mechanism of the considered protruding element. Keywords: masonry building, freestanding elements, floor spectra, linear and nonlinear kinematic analysis. 1501 COMPDYN 2019 7 th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering M. Papadrakakis, M. Fragiadakis (eds.) Crete, Greece, 24–26 June 2019 Available online at www.eccomasproceedia.org Eccomas Proceedia COMPDYN (2019) 1501-1513 ISSN:2623-3347 © 2019 The Authors. Published by Eccomas Proceedia. Peer-review under responsibility of the organizing committee of COMPDYN 2019. doi: 10.7712/120119.7014.19565