Effects of Pre-existing Damage on Fragility of URM and RC Frame Buildings

Iñarritu, P. García de Quevedo; Šipčić, Nevena; Kohrangi, Mohsen; Bazzurro, Paolo

doi:10.1007/978-3-030-73932-4_2

Cited by 4 publications

(5 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Case‐in‐point, it was shown in the previous paragraphs that, for a given displacement demand, other structural parameters that can be said to be related to the degree of damage of a structure, such as the amount of stiffness or maximum restoring force lost, exhibit variability. It has also been suggested that, due to this variability, displacement‐based thresholds may have to be adjusted for the purposes of state‐dependent fragility definition, 37 or more elaborate

EDPs

should be used instead 38 . In this study, the amount of residual displacement is also involved in the damage measure for state‐dependent fragility assessment, by assuming that the transition thresholds from damage state

D{S}_i

D{S}_j

can be obtained as:

$$\begin{equation}\ {\delta }_{\left.

…”

Section: State‐dependent Seismic Structural Fragilitymentioning

confidence: 99%

Simplified state‐dependent seismic fragility assessment

Orlacchio,

Baltzopoulos,

Iervolino

2024

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

Earthquakes are clustered in time and space; therefore, structures may be subjected to multiple consecutive instances of potentially damaging shaking, with insufficient in‐between time for repair operations to take place. Methodologies to evaluate the risk dynamics in this situation require vulnerability models that are able to capture the transitions between damage states, from the intact conditions to failure, due to multiple damaging earthquakes, that is, state‐dependent fragility curves. One of the state‐of‐the‐art methods for the assessment of structure‐specific state‐dependent fragility curves relies on a variant of incremental dynamic analysis (IDA), which is often termed back‐to‐back or B2B‐IDA. The computational costs typically involved in B2B‐IDA motivate attempts to simplify the evaluation of state‐dependent fragility curves. This paper presents a simplified method for multi‐story moment‐resisting frame structures, based on pushover analysis in conjunction with a predictive model for the main features of a damaged structural system, such as residual deformations and loss of stiffness and/or strength. The predictive model enables the probabilistic definition of the post‐earthquake pushover curve of a damaged structural system, given the displacement demand imposed by a preceding damaging shock. The state‐dependent fragility curves are then evaluated via IDA of single‐degree‐of‐freedom oscillators based on these pushover curves. Illustrative applications validate the ability of the proposed methodology to provide state‐dependent fragilities with reduced computational costs compared to the back‐to‐back IDA method.

show abstract

EDPs

D{S}_i

D{S}_j

can be obtained as:

$$\begin{equation}\ {\delta }_{\left.

…”

Section: State‐dependent Seismic Structural Fragilitymentioning

confidence: 99%

Simplified state‐dependent seismic fragility assessment

Orlacchio,

Baltzopoulos,

Iervolino

2024

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

show abstract

“…Artificial MS-AS sequences can be derived by randomly combining two MSs (e.g., Aljawhari et al, 2020;Gentile and Galasso, 2021a) or by adopting more advanced approaches involving the combination of ground-motion records by using an MS-AS correlation model (e.g., Papadopoulos et al, 2020). Finally, artificial MS-AS sequences can be used in addition to real ones to improve the ground-motion sequence set and cover a wider range of MS-AS IMs (e.g., de Quevedo Iñarritu et al, 2021).…”

Section: Non-linear Dynamic Analyses On Mdof Numerical Modelsmentioning

confidence: 99%

“…However, current seismic-risk assessment studies typically neglect the effects of seismic damage accumulation (as well as those due to time dependencies in seismic hazard; e.g., Iacoletti et al, 2022), considering that immediate repair takes place after every earthquake. Neglecting the impact of prior earthquake damage may lead to an underestimation of structural vulnerability and loss metrics, thus affecting decision-making for defining emergency planning strategies and insurance policies (e.g., de Quevedo Iñarritu et al, 2021). Moreover, a detailed assessment of the residual capacity of earthquake-damaged buildings to sustain subsequent seismic events is critical to support decision-making on both re-occupancy and repair vs. demolition, as well as for the selection, design, and implementation of suitable techniques to 'restore' the building to its undamaged conditions (e.g., Cuevas and Pampanin, 2017;Pampanin, 2021).…”

Section: Introduction and Motivationsmentioning

confidence: 99%

“…In turn, this may lead to statistical inconsistencies in the state-dependent fragility results (e.g., fragility curves crossing among various damage states). To overcome this issue, some recent studies in the literature (e.g., Gentile and Galasso, 2021a;de Quevedo Iñarritu et al, 2021;Kalateh-Ahani and Amiri, 2021;Yu et al, 2021;Zhou et al, 2021) suggested performing state-dependent fragility analyses considering energy-based EDPs. One of the main advantages of energy-based approaches is that they rely on scalar measures (e.g., dynamic hysteretic energy) that monotonically increase with the length of the ground-motion excitation (or the number of subsequent excitations).…”

Section: Introduction and Motivationsmentioning

confidence: 99%

See 1 more Smart Citation

Energy-based procedures for seismic fragility analysis of mainshock-damaged buildings

Pedone

Gentile

Galasso

et al. 2023

Front. Built Environ.

View full text Add to dashboard Cite

In recent decades, significant research efforts have been devoted to developing fragility and vulnerability models for mainshock-damaged buildings, i.e., depending on the attained damage state after a mainshock ground motion (state-dependent fragility/vulnerability relationships). Displacement-based peak quantities, such as the maximum interstory drift ratio, are widely adopted in fragility analysis to define both engineering demands and structural capacities at the global and/or local levels. However, when considering ground-motion sequences, the use of peak quantities may lead to statistical inconsistencies (e.g., fragility curves’ crossings) due to inadequate consideration of damage accumulation. In this context, energy-based engineering demand parameters (EDPs), explicitly accounting for cumulative damage, can help address this issue. This paper provides an overview of recent findings on the development of aftershock-fragility models of mainshock-damaged buildings. Particular focus is given to state-of-the-art frameworks for fragility analyses based on cumulative damage parameters. Moreover, a literature review on damage indices and energy-based concepts and approaches in earthquake engineering is reported to better understand the main advantages of the mostly adopted energy-based parameters, as well as their limitations. Different refinement levels of seismic response analyses to derive fragility relationships of mainshock-damaged buildings are also discussed. Finally, the benefits of adopting energy-based EDPs rather than, or in addition to, peak quantities in state-dependent fragility analyses are demonstrated on a reinforced concrete frame building. Specifically, a refined lumped plasticity modeling approach is adopted, and sequential cloud-based time-history analyses of a Multi-Degree-of-Freedom (MDoF) model are carried out. The results highlight that energy-based approaches for fragility analysis effectively capture damage accumulation during earthquake sequences without inconsistencies in the obtained statistical models. On the other hand, estimating global or local structural capacity in terms of cumulative EDPs is still challenging. Further experimental data are needed to better calibrate the quantification of energy-based damaged states.

show abstract

“…22,23 Using more advanced damage measures, such as those capable of combining both displacement-and energy-based measures 24 Reinhorn and Valles 25 ; Chung et al 26 ; Remki et al 27 , in place of simple displacement-based ones seems a legitimate and more practical solution. [28][29][30] Among other damage measures, several studies showed the better performance of Park and Ang damage index 24 for assessing cumulative damage in URM buildings [31][32][33] in comparison with displacement-based damage measures. These damage indices, however, were originally developed for frame structures or RC members, and therefore, as is their application for URM buildings is questionable.…”

Section: Introductionmentioning

confidence: 99%

Damage assessment of unreinforced masonry buildings incorporating damage accumulation

Inarritu,

Kohrangi,

Bazzurro

2024

Earthq Engng Struct Dyn

View full text Add to dashboard Cite

Recent earthquakes have shown susceptibility of unreinforced masonry (URM) buildings to damage accumulation in seismic sequences or long duration ground motions. Current structural modelling approaches commonly disregard the damage accumulation in URM buildings or they are unable to accurately capture this phenomenon unless sophisticated FEM models are employed. Such models are not feasible in risk‐based applications given the required large number of dynamic analyses needed to develop robust fragility and vulnerability curves. On the other hand, the common displacement‐based engineering demand parameters (EDP), such as inter‐story drift ratio, fail to capture the impact of damage accumulation in simpler, more manageable models. An alternative is to use advanced damage indices that are capable of monitoring the monotonic accumulation of damages. This study proposes a displacement‐ and energy‐based damage index that uses, as the basis, the Park and Ang damage index, modified and calibrated through experimental data of individual URM elements. Our calibration procedure maps the physical observed damage states to the hysteretic response of the elements. Consequently, damage on the individual elements is aggregated to define a global damage state at building level. Validation is carried out based on an equivalent frame model of a building tested on a shake table. Additionally, the model is subjected to multiple ground motions of seismic sequences and to long‐duration ground motions to evaluate the performance of the proposed damage index. In comparison with displacement‐based damage measures, the proposed damage index shows a superior ability to capture cumulative damage, even when simplified models are employed.

show abstract

Effects of Pre-existing Damage on Fragility of URM and RC Frame Buildings

Cited by 4 publications

References 25 publications

Simplified state‐dependent seismic fragility assessment

Simplified state‐dependent seismic fragility assessment

Energy-based procedures for seismic fragility analysis of mainshock-damaged buildings

Damage assessment of unreinforced masonry buildings incorporating damage accumulation

Contact Info

Product

Resources

About