Seismic response and capacity of inelastic acceleration‐sensitive nonstructural elements subjected to building floor motions
Gennaro Magliulo, Danilo D’Angela
Abstract
Abstract The paper investigates the seismic response of nonstructural elements (NEs), focusing on acceleration‐sensitive components housed in buildings, modelled as inelastic Ibarra–Medina–Krawinkler (SDOF) systems. Incremental dynamic analysis (IDA) is carried out considering (a) representative suites of building floor motions (real loading histories recorded within reinforced concrete (RC) buildings and table testing protocol inputs) and (b) a wide range of NE models (with elastic frequencies ranging within 1–9 Hz). The Ibarra‐Medina‐Krawinkler (IMK) model was implemented in OpenSees, defining the key modeling parameters according to the formulations provided by Lignos and Krawinkler. Both IDA curves and component (acceleration) amplification factor (CAF) are characterized, also considering statistical measures. The seismic capacity of the investigated NEs is estimated through fragility curves, accounting for five incremental damage states (DSs). The fragility parameters are correlated with the frequency of the NE models, and (statistical‐based) closed‐form capacity criteria are provided. The study provides a robust technical and scientific methodological framework for assessing the seismic capacity of NEs that can be modeled by inelastic SDOF systems. The findings have a potential major impact on both research and practice, enriching scientific knowledge and providing useful applicative tools. In particular, quantitative response and capacity measures are supplied, and the developed capacity criteria can be particularly useful for expeditious but reliable design and assessment, as well as for comparison purposes.