Characterization of local and global capacity criteria for collapse assessment of code-conforming RC buildings

Abstract

The paper investigates both local and global capacity criteria for collapse assessment of RC frame buildings. Both literature and regulations criteria are considered, also including the formulation recommended in the draft of the new Eurocode 8 (part 3) and other collapse criteria never investigated. The case studies consist of low-rise bare and infilled frame buildings, which are designed according to the Italian code provisions considering low-to-high seismicity sites in Italy. The seismic demand is estimated by performing multiple-stripe analysis based on inelastic modeling, also including the presence of the infills. The capacity assessment and the performance evaluation associated with the (building) collapse are carried out according to the latest approaches and methodologies of performance-based earthquake engineering. The investigated capacity criteria are characterized as a result of the collapse assessment in terms of (a) collapse demand to capacity ratios, (b) collapse fragility curves, (c) collapse margin ratios and probabilities, and (d) inter-capacity margin ratios. The findings provide novel information and technical insights into the influence of the collapse capacity criteria selection on the collapse features of the investigated buildings. In particular, the capacity criteria are quantitatively correlated to the building collapse performance, also outlining safety and economic considerations.

Seismic response and capacity of inelastic acceleration‐sensitive nonstructural elements subjected to building floor motions

“…F I G U R E 1 Numerical modeling: (A) structural modeling scheme (in-series element), (B) IMK model and schematic cyclic response (as provided in OpenSees), 42,44,45 (C) backbone schematic and hysteretic parameters, 47 and backbone curves of the investigated SDOF models.…”

“…The elastic stiffness of both spring and elastic element was assigned so as to have a ratio of the two elements' stiffness equal to ten, resulting in a global in-series stiffness equal to the member's stiffness, according to the literature (Refs. 43,47). UniaxialMaterial ModIMKPeakOriented zerolength and ElasticBeamColumn elements were used to model the spring and the elastic elements, respectively.…”

“…Rayleigh damping was assigned to the elastic elements, assuming a damping ratio equal to 5%. 47,51 Incremental analyses were performed considering PFA as an IM and lateral mass displacement Δ as an EDP. The analyses were carried out from PFA equal to 0.05 g up to failure of all models, without considering structural resurrection.…”

Explainable probabilistic deep learning framework for seismic assessment of structures using distribution‐free prediction intervals

“…It is worth mentioning that elastoplastic force–deformation model provides reasonably accurate drift values when compared to other force–deformation models for structural system (FEMA 440 and ASCE 41‐17). The lumped mass technique is used to distribute the modal mass of the structure to the nodes of the beams and columns (D'Angela et al., 2021). Newmark integration technique is used to implement the direct integration method for conducting NLTHA.…”

Evaluation of models of the flexural response of rectangular reinforced concrete columns in the post-capping region

“…[2,3,4,5]) and is still relevant today, as researchers are looking for simple and effective models to be used in seismic risk assessment studies (e.g. [6,7,8]).…”