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This paper presents a general seismic classification procedure for acceleration‐sensitive non‐structural elements (NSEs) based on seismic qualification shake table testing and provides an application example for electrical cabinets in Italy. The proposed seismic classification procedure requires the definition of a set of required response spectra (RRS) for qualification shake table testing defined at different seismic hazard levels and the definition of a formal procedure to generate a test input motion. Each required response spectrum at a given seismic hazard level is then linked to different class levels and the requirements that an NSE should present to achieve each class level are defined. Using this framework, a seismic classification procedure for NSEs is developed for Italy, in which, the RRS are defined according to a peak floor spectral acceleration seismic hazard map of the territory so as to predefine regions in which an NSE belonging to a given class can be installed or not according to either a life safety performance objective or a continuous operation performance objective. Also, the limitations of the proposed seismic classification procedure are outlined. Finally, a nominal application example is presented in which four electrical cabinet specimens were tested on a shake table and their class levels were defined. The results of the application example are used to nominally show how the proposed classification procedure could be applied to discriminate between different types of the same NSE depending on the specific desired application. [ABSTRACT FROM AUTHOR]

Direct displacement-based seismic design has been proposed for pallet-type steel storage racks. Damping models are developed in this study for pallet-type steel storage racks in the down-aisle and cross-aisle directions for use in direct displacement-based seismic design. The damping models are developed using results from reversed cyclic tests at a component level or at a system level. Jacobsen's approach is used to develop a first set of damping models. The damping models are then assessed using results from nonlinear time-history analyses. Finally, the damping models are calibrated using an iterative procedure based on results from nonlinear time-history analyses. [ABSTRACT FROM AUTHOR]

Direct displacement-based seismic design has been recently proposed for the seismic design of non-structural building elements. This paper deals with the development of damping models, relating equivalent viscous damping ratio to drift amplitude, for suspended piping trapeze restraint installations for direct displacement-based seismic design. The damping models are developed using reversed cyclic test data available in the literature. First, damping models are proposed using Jacobsen's equal area approach. The damping models developed using Jacobsen's approach are then assessed and calibrated using nonlinear time history analyses of single degree-of-freedom archetypes representing suspended piping trapeze restraint installations in buildings. [ABSTRACT FROM AUTHOR]

Summary: The achievement of adequate performance objectives for buildings under increasing seismic intensities is not only related to the performance of structural members but also to the behavior of nonstructural elements. The need to properly design nonstructural elements for earthquakes has been largely demonstrated in the last few years and has become an important objective within the earthquake engineering community. A crucial aspect in the proper design of nonstructural elements is the definition of the seismic demand in terms of both absolute acceleration and relative displacement floor response spectra. In the first part of this study, relative displacement and absolute acceleration floor response spectra were computed for four reinforced concrete moment‐resisting archetype frames via dynamic time‐history analyses and were compared with floor response spectra predicted by means of two recent simplified methodologies available in the literature. It was observed that one of the existing methodologies is generally unable to predict consistent absolute acceleration and relative displacement floor response spectra. An improved procedure is developed for estimating consistent floor response spectra for building structures subjected to low and medium‐high seismic intensities. This new procedure improves the predictions of a relative displacement floor response spectrum by constraining its ordinates at long nonstructural periods to the expected peak absolute displacement of the floor. The resulting acceleration and relative displacement response spectra are then consistently related by the well‐known pseudo‐spectral relationship over the entire nonstructural period range. The effectiveness of the proposed methodology was appraised against floor response spectra computed from nonlinear time‐history analyses. [ABSTRACT FROM AUTHOR]