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Reliable seismic hazard analyses are crucial to mitigate seismic risk. When dealing with induced seismicity the standard Probabilistic Seismic Hazard Analysis (PSHA) has to be modified because of the peculiar characteristics of the induced events. In particular, the relative shallow depths, small magnitude, a correlation with field operations, and eventually non-Poisson recurrence time. In addition to the well-known problem of estimating the maximum expected magnitude, it is important to take into account how the industrial field operations affect the temporal and spatial distribution of the earthquakes. In fact, during specific stages of the project the seismicity may be hard to be modelled as a Poisson process—as usually done in the standard PSHA—and can cluster near the well or migrate toward hazardous known or—even worse—not known faults. Here we present a technique in which we modify the standard PSHA to compute time-dependent seismic hazard. The technique allows using non-Poisson models (BPT, Weibull, gamma and ETAS) whose parameters are fitted using the seismicity record during distinct stages of the field operations. As a test case, the procedure has been implemented by using data recorded at St. Gallen deep geothermal field, Switzerland, during fluid injection. The results suggest that seismic hazard analyses, using appropriate recurrence model, ground motion predictive equations, and maximum magnitude allow the expected ground-motion to be reliably predicted in the study area. The predictions can support site managers to decide how to proceed with the project avoiding adverse consequences.
Vincenzo Convertito; Hossein Ebrahimian; Ortensia Amoroso; Fatemeh Jalayer; Raffaella De Matteis; Paolo Capuano. Time-Dependent Seismic Hazard Analysis for Induced Seismicity: The Case of St Gallen (Switzerland), Geothermal Field. Energies 2021, 14, 2747 .
AMA StyleVincenzo Convertito, Hossein Ebrahimian, Ortensia Amoroso, Fatemeh Jalayer, Raffaella De Matteis, Paolo Capuano. Time-Dependent Seismic Hazard Analysis for Induced Seismicity: The Case of St Gallen (Switzerland), Geothermal Field. Energies. 2021; 14 (10):2747.
Chicago/Turabian StyleVincenzo Convertito; Hossein Ebrahimian; Ortensia Amoroso; Fatemeh Jalayer; Raffaella De Matteis; Paolo Capuano. 2021. "Time-Dependent Seismic Hazard Analysis for Induced Seismicity: The Case of St Gallen (Switzerland), Geothermal Field." Energies 14, no. 10: 2747.
On Sunday November 12, 2017, at 18:18:16 UTC, (21:48:16 local time), a strong earthquake with Mw7.3 occurred in western Iran in the border region between Iran and Iraq in vicinity of the Sarpol-e Zahab town. Unfortunately, this catastrophic seismic event caused 572 causalities, thousands of injured and vast amounts of damage to the buildings, houses and infrastructures in the epicentral area. The mainshock of this seismic sequence was felt in the entire western and central provinces of Iran and surrounding areas. The main event was preceded by a foreshock with magnitude 4.5 about 43 minutes before the mainshock that warned the local residence to leave their home and possibly reduced the number of human casualties. More than 2500 aftershocks with magnitude greater than 2.5 have been reported up to January 2019 with the largest registered aftershock of Mw6.4. A novel and fully-probabilistic procedure is adopted for providing spatio-temporal predictions of aftershock occurrence in a prescribed forecasting time interval (in the order of hours or days). The procedure aims at exploiting the information provided by the ongoing seismic sequence in quasi-real time. The versatility of the Bayesian inference is exploited to adaptively update the forecasts based on the incoming information as it becomes available. The aftershock clustering in space and time is modelled based on an Epidemic Type Aftershock Sequence (ETAS). One of the main novelties of the proposed procedure is that it considers the uncertainties in the aftershock occurrence model and its model parameters. This is done by moving within a framework of robust reliability assessment which enables the treatment of uncertainties in an integrated manner. Pairing up the Bayesian robust reliability framework and the suitable simulation schemes (Markov Chain Monte Carlo Simulation) provides the possibility of performing the whole forecasting procedure with minimum (or no) need of human interference. The fully simulation-based procedure is examined for both Bayesian model updating of ETAS spatio-temporal model and robust operational forecasting of the number of events of interest expected to happen in various time intervals after main events within the sequence. The seismicity is predicted within a confidence interval from the mean estimate.
Fatemeh Jalayer; Hossein Ebrahimian. Operational Aftershock Forecasting for 2017-2018 Seismic Sequence in Western Iran. 2021, 1 .
AMA StyleFatemeh Jalayer, Hossein Ebrahimian. Operational Aftershock Forecasting for 2017-2018 Seismic Sequence in Western Iran. . 2021; ():1.
Chicago/Turabian StyleFatemeh Jalayer; Hossein Ebrahimian. 2021. "Operational Aftershock Forecasting for 2017-2018 Seismic Sequence in Western Iran." , no. : 1.
The Italian code requires spectrum compatibility with mean spectrum for a suite of accelerograms selected for time-history analysis. Although these requirements define minimum acceptability criteria, it is likely that code-based non-linear dynamic analysis is going to be done based on limited number of records. Performance-based safety-checking provides formal basis for addressing the record-to-record variability and the epistemic uncertainties due to limited number of records and in the estimation of the seismic hazard curve. “Cloud Analysis” is a non-linear time-history analysis procedure that employs the structural response to un-scaled ground motion records and can be directly implemented in performance-based safety-checking. This paper interprets the code-based provisions in a performance-based key and applies further restrictions to spectrum-compatible record selection aiming to implement Cloud Analysis. It is shown that, by multiplying a closed-form coefficient, code-based safety ratio could be transformed into simplified performance-based safety ratio. It is shown that, as a proof of concept, if the partial safety factors in the code are set to unity, this coefficient is going to be on average slightly larger than unity. The paper provides the basis for propagating the epistemic uncertainties due to limited sample size and in the seismic hazard curve to the performance-based safety ratio both in a rigorous and simplified manner. If epistemic uncertainties are considered, the average code-based safety checking could end up being unconservative with respect to performance-based procedures when the number of records is small. However, it is shown that performance-based safety checking is possible with no extra structural analyses.
Fatemeh Jalayer; Hossein Ebrahimian; Andrea Miano. Record-to-record variability and code-compatible seismic safety-checking with limited number of records. Bulletin of Earthquake Engineering 2021, 1 -36.
AMA StyleFatemeh Jalayer, Hossein Ebrahimian, Andrea Miano. Record-to-record variability and code-compatible seismic safety-checking with limited number of records. Bulletin of Earthquake Engineering. 2021; ():1-36.
Chicago/Turabian StyleFatemeh Jalayer; Hossein Ebrahimian; Andrea Miano. 2021. "Record-to-record variability and code-compatible seismic safety-checking with limited number of records." Bulletin of Earthquake Engineering , no. : 1-36.
In performance‐based earthquake engineering, the suitability of an intensity measure (IM) is expressed through its efficiency and sufficiency. An efficient IM leads to a small record‐to‐record variability in the estimation of demand given seismic intensity. A sufficient IM is one that renders the estimation of demand for all intensity levels independent of all other ground motion parameters. Given that establishing sufficiency is not a trivial task, the relative sufficiency measure (RSM) has been proposed previously based on information theory concepts. RSM can be employed for quantifying the relative sufficiency of an IM with respect to another IM by the amount of extra information that it relays on average about the ground motion for the estimation of a demand parameter of interest. RSM has been so far conditioned on a linear logarithmic regression probability model, better known as the Cloud Analysis (CA), which relies on unscaled ground‐motion records. This work lays out the methodology for estimating both the efficiency and RSM in terms of the damage measure directly (instead of demand parameter) and by employing alternative nonlinear dynamic analysis procedures (NDAPs), such as, a modified version of CA that considers the collapse‐cases explicitly and the incremental dynamic analysis. It is demonstrated that the RSM can be sensitive to the NDAP employed, while it does not demonstrate significant sensitivity to the limit state of interest. An alternative measure of efficiency (known in literature as proficiency), directly measured as the dispersion in the fragility curve, shows more sensitivity to the limit state.
Hossein Ebrahimian; Fatemeh Jalayer. Selection of seismic intensity measures for prescribed limit states using alternative nonlinear dynamic analysis methods. Earthquake Engineering & Structural Dynamics 2020, 50, 1235 -1250.
AMA StyleHossein Ebrahimian, Fatemeh Jalayer. Selection of seismic intensity measures for prescribed limit states using alternative nonlinear dynamic analysis methods. Earthquake Engineering & Structural Dynamics. 2020; 50 (5):1235-1250.
Chicago/Turabian StyleHossein Ebrahimian; Fatemeh Jalayer. 2020. "Selection of seismic intensity measures for prescribed limit states using alternative nonlinear dynamic analysis methods." Earthquake Engineering & Structural Dynamics 50, no. 5: 1235-1250.
Recent earthquakes have exposed the vulnerability of existing buildings; this is demonstrated by damage incurred after moderate-to-high magnitude earthquakes. This stresses the need to exploit available data from different sources to develop reliable seismic risk components. As far as it regards empirical fragility assessment, accurate estimation of ground-shaking at the location of buildings of interest is as crucial as the accurate evaluation of observed damage for these buildings. This implies that explicit consideration of the uncertainties in the prediction of ground shaking leads to more robust empirical fragility curves. In such context, the simulation-based methods can be employed to provide fragility estimates that integrate over the space of plausible ground-shaking fields. These ground-shaking fields are generated according to the joint probability distribution of ground-shaking at the location of the buildings of interest considering the spatial correlation structure in the ground motion prediction residuals and updated based on the registered ground shaking data and observed damage. As an alternative to the embedded coefficients in the ground motion prediction equations accounting for subsoil categories, stratigraphic coefficients can be applied directly to the ground motion fields at the engineering bedrock level. Empirical fragility curves obtained using the observed damage in the aftermath of Amatrice Earthquake for residential masonry buildings show that explicit consideration of the uncertainty in the prediction of ground-shaking significantly affects the results.
A. Miano; F. Jalayer; G. Forte; A. Santo. Empirical fragility assessment using conditional GMPE-based ground shaking fields: application to damage data for 2016 Amatrice Earthquake. Bulletin of Earthquake Engineering 2020, 18, 6629 -6659.
AMA StyleA. Miano, F. Jalayer, G. Forte, A. Santo. Empirical fragility assessment using conditional GMPE-based ground shaking fields: application to damage data for 2016 Amatrice Earthquake. Bulletin of Earthquake Engineering. 2020; 18 (15):6629-6659.
Chicago/Turabian StyleA. Miano; F. Jalayer; G. Forte; A. Santo. 2020. "Empirical fragility assessment using conditional GMPE-based ground shaking fields: application to damage data for 2016 Amatrice Earthquake." Bulletin of Earthquake Engineering 18, no. 15: 6629-6659.
Methodology:
The implementation of short-term forecasts for emergency response management in the immediate aftermath of a seismic event, and in the presence of an ongoing seismic sequence, requires two basic components: scientific advisories expressed in terms of risk assessment, and protocols that establish how the scientific results can be translated into decisions/actions for risk mitigation. The operational earthquake forecasting framework is geared towards providing scientific advisories in the form of time-dependent probabilities expressing seismicity, hazard and risk that can be practically translated into decisions. Considering the triggered sequence of aftershocks in the process of post-event decision-making and prioritization of emergency operations still seems to need and to deserve much more attention. To this end, the adopted novel and fully-probabilistic procedure succeeds in providing spatio-temporal predictions of aftershock occurrence in a prescribed forecasting time interval (in the order of hours or days). The procedure aims at exploiting the information provided by the ongoing seismic sequence in quasi-real time considering the time needed for registering and transmitting the data. The versatility of the Bayesian inference is exploited to adaptively update the forecasts based on the incoming information as it becomes available. The aftershock clustering in space and time is modelled based on an Epidemic Type Aftershock Sequence (ETAS). One of the main novelties of the proposed procedure is that it considers the uncertainties in the aftershock occurrence model and its model parameters. This is done by moving within a framework of robust reliability assessment which enables the treatment of uncertainties in an integrated manner. Pairing up the Bayesian robust reliability framework and the suitable simulation schemes (Markov Chain Monte Carlo Simulation) provides the possibility of performing the whole forecasting procedure with minimum (or no) need of human interference.
Application:
This procedure is demonstrated through a retrospective application to early forecasting of seismicity associated with the 2017 Sarpol-e Zahab seismic sequence activities. On Sunday November 12, 2017, at 18:18:16 UTC, (21:48:16 local time), a strong earthquake with Mw7.3 occurred in western Iran in the border region between Iran and Iraq in vicinity of the Sarpol-e Zahab town. Unfortunately, this catastrophic seismic event caused 572 causalities, thousands of injured and vast amounts of damage to the buildings, houses and infrastructures in the epicentral area. The mainshock of this seismic sequence was felt in the entire western and central provinces of Iran and surrounding areas. The main event was preceded by a foreshock with magnitude 4.5 about 43 minutes before the mainshock that warned the local residence to leave their home and possibly reduced the number of human casualties. More than 2500 aftershocks with magnitude greater than 2.5 have been reported up to January 2019 with the largest registered aftershock of Mw6.4. The fully simulation-based procedure is examined for both Bayesian model updating of ETAS spatio-temporal model and robust operational forecasting of the number of events of interest expected to happen in various time intervals after main events within the sequence. The seismicity is predicted within a confidence interval from the mean estimate.
Hossein Ebrahimian; Fatemeh Jalayer; Hamid Zafarani. Operational Aftershock Forecasting for Mw7.3 Sarpol-e Zahab (2017) Earthquake in Western Iran. 2020, 1 .
AMA StyleHossein Ebrahimian, Fatemeh Jalayer, Hamid Zafarani. Operational Aftershock Forecasting for Mw7.3 Sarpol-e Zahab (2017) Earthquake in Western Iran. . 2020; ():1.
Chicago/Turabian StyleHossein Ebrahimian; Fatemeh Jalayer; Hamid Zafarani. 2020. "Operational Aftershock Forecasting for Mw7.3 Sarpol-e Zahab (2017) Earthquake in Western Iran." , no. : 1.
Modelling uncertainty can significantly affect the structural seismic reliability assessment. However, the limit state excursion due to this type of uncertainty may not be described by a Poisson process as it lacks renewal properties with the occurrence of each earthquake event. Furthermore, considering uncertainties related to ground motion representation by employing recorded ground motions together with modelling uncertainties is not a trivial task. Robust fragility assessment, proposed previously by the authors, employs the structural response to recorded ground motion as data in order to update prescribed seismic fragility models. Robust fragility can be extremely efficient for considering also the structural modelling uncertainties by creating a dataset of one‐to‐one assignments of structural model realizations and as‐recorded ground motions. This can reduce the computational effort by more than 1 order of magnitude. However, it should be kept in mind that the fragility concept itself is based on the underlying assumption of Poisson‐type renewal. Using the concept of updated robust reliability, considering both the uncertainty in ground motion representation based on as‐recorded ground motion and non ergodic modelling uncertainties, the error introduced through structural reliability assessment by using the robust fragility is quantified. It is shown through specific application to an existing RC frame that this error is quite small when the product of the time interval and the standard deviation of failure rate is small and is on the conservative side.
Fatemeh Jalayer; Hossein Ebrahimian. Seismic reliability assessment and the nonergodicity in the modelling parameter uncertainties. Earthquake Engineering & Structural Dynamics 2020, 49, 434 -457.
AMA StyleFatemeh Jalayer, Hossein Ebrahimian. Seismic reliability assessment and the nonergodicity in the modelling parameter uncertainties. Earthquake Engineering & Structural Dynamics. 2020; 49 (5):434-457.
Chicago/Turabian StyleFatemeh Jalayer; Hossein Ebrahimian. 2020. "Seismic reliability assessment and the nonergodicity in the modelling parameter uncertainties." Earthquake Engineering & Structural Dynamics 49, no. 5: 434-457.
Probabilistic seismic hazard analysis (PSHA) encompasses quantitative estimation of seismic hazard at a site by considering all plausible earthquake scenarios. The outcome of a PSHA is often reported as the mean rate of exceeding a specific ground motion intensity measure at a given site. This study attempts to perform PSHA for the western area of the city Naples (southern Italy) by employing the most advanced methods and new databases; namely, DISS3.2 (Database of Individual Seismogenic Sources) and CPTI15 (Parametric Catalogue of Italian Earthquakes). Seismogenic models include individual seismogenic structures/faults liable to generating major earthquakes with magnitude greater than 5.5, and background areal source model to evaluate the effect of earthquakes with magnitude less than 5.5. The PSHA is built up based on the long-term earthquake recurrence on seismogenic tectonic faults and the spatial distribution of historical earthquakes. Site amplification is considered based on seismic microzonation maps derived for the western area of Naples. The microzonation maps delineate expected levels of ground motion amplification based on reliable geological and geotechnical subsoil models. Hazard maps are derived for a number of return periods for ground-shaking in terms of peak ground acceleration and 5%-damped pseudo-spectral acceleration at a range of periods that are representative of the existing construction within the area. Detailed comparisons of the PSHA results with Italian national hazard maps and the code-based design spectra emphasize the importance of performing site-specific PSHA with explicit consideration of site effects.
Hossein Ebrahimian; Fatemeh Jalayer; Giovanni Forte; Vincenzo Convertito; Valeria Licata; Anna D’Onofrio; Antonio Santo; Francesco Silvestri; Gaetano Manfredi. Site-specific probabilistic seismic hazard analysis for the western area of Naples, Italy. Bulletin of Earthquake Engineering 2019, 17, 4743 -4796.
AMA StyleHossein Ebrahimian, Fatemeh Jalayer, Giovanni Forte, Vincenzo Convertito, Valeria Licata, Anna D’Onofrio, Antonio Santo, Francesco Silvestri, Gaetano Manfredi. Site-specific probabilistic seismic hazard analysis for the western area of Naples, Italy. Bulletin of Earthquake Engineering. 2019; 17 (9):4743-4796.
Chicago/Turabian StyleHossein Ebrahimian; Fatemeh Jalayer; Giovanni Forte; Vincenzo Convertito; Valeria Licata; Anna D’Onofrio; Antonio Santo; Francesco Silvestri; Gaetano Manfredi. 2019. "Site-specific probabilistic seismic hazard analysis for the western area of Naples, Italy." Bulletin of Earthquake Engineering 17, no. 9: 4743-4796.
In different high seismic regions around the world, post-earthquake reconnaissance has shown that nonductile concrete frame structures are much more susceptible to collapse than modern code-conforming frames. Therefore, for this type of structures, it is necessary to accurately model materials and members to capture the flexure, shear, and flexure-shear failure modes in members and the potential collapse of the structure. In this paper, alternative retrofit methods are evaluated for these older frame buildings using a probability-based framework, based on nonlinear dynamic cloud analysis, in order to assess the structural performance and safety at each chosen performance level. As a case study, the longitudinal frame of an existing building is modeled, including the effect of flexural-shear-axial load interaction and the longitudinal bar slip deformation component in order to be able to capture column shear and axial failures. The critical demand to capacity ratio, corresponding to the component or mechanism that leads the structure closest to the onset of limit state (e.g., near collapse), is adopted as the structural response parameter. This structural response parameter, that is equal to unity at the onset of limit state, can encompass both ductile and brittle failure mechanisms. It can also register a possible shift in the governing failure mechanism with increasing intensity. Finally, the estimates of expected life cycle cost are compared for the retrofit methods considered in this research.
Andrea Miano; Halil Sezen; Fatemeh Jalayer; Andrea Prota. Performance Based Assessment and Retrofit of Nonductile Existing Reinforced Concrete Structures. Structures Conference 2018 2018, 1 .
AMA StyleAndrea Miano, Halil Sezen, Fatemeh Jalayer, Andrea Prota. Performance Based Assessment and Retrofit of Nonductile Existing Reinforced Concrete Structures. Structures Conference 2018. 2018; ():1.
Chicago/Turabian StyleAndrea Miano; Halil Sezen; Fatemeh Jalayer; Andrea Prota. 2018. "Performance Based Assessment and Retrofit of Nonductile Existing Reinforced Concrete Structures." Structures Conference 2018 , no. : 1.
Incremental dynamic analysis (IDA) leads to curves expressed in terms of structural response versus intensity, commonly known as the IDA curves. It is known that implementation of IDA usually involves significant computational effort and most often significant scaling of the original records to various intensity levels. Employing as the performance variable the critical demand to capacity ratio (DCR) throughout the structure, which is equal to unity at the onset of the limit state, facilitates the identification of the intensity values at the onset of a desired limit state and hence the implementation of the IDA procedure. Employing the structural response to un-scaled records and the corresponding regression-based response predictions (a.k.a., the “Cloud Analysis”) helps in identifying the range of intensity values corresponding to demand to capacity ratio values in the vicinity of unity. The Cloud to IDA procedure for structural fragility assessment is proposed on the premise of exploiting the Cloud Analysis results to obtain the IDA curves both with minimum number of analyses and minimum amount of scaling. The transverse frame of a shear-critical 7-story older RC building in Van Nuys, CA, which is modeled in Opensees with fiber-section considering the flexural-shear-axial interactions and the bar slip, is employed as a case study. It is demonstrated, by comparing the results to IDA and other state of the art non-linear dynamic procedures based on no scaling or spectral-shape-compatible scaling, that the Cloud to IDA procedure leads to reliable results in terms of structural fragility and risk for the prescribed limit state.
Andrea Miano; Fatemeh Jalayer; Hossein Ebrahimian; Andrea Prota. Cloud to IDA: Efficient fragility assessment with limited scaling. Earthquake Engineering & Structural Dynamics 2017, 47, 1124 -1147.
AMA StyleAndrea Miano, Fatemeh Jalayer, Hossein Ebrahimian, Andrea Prota. Cloud to IDA: Efficient fragility assessment with limited scaling. Earthquake Engineering & Structural Dynamics. 2017; 47 (5):1124-1147.
Chicago/Turabian StyleAndrea Miano; Fatemeh Jalayer; Hossein Ebrahimian; Andrea Prota. 2017. "Cloud to IDA: Efficient fragility assessment with limited scaling." Earthquake Engineering & Structural Dynamics 47, no. 5: 1124-1147.
In the immediate aftermath of a strong earthquake and in the presence of an ongoing aftershock sequence, scientific advisories in terms of seismicity forecasts play quite a crucial role in emergency decision-making and risk mitigation. Epidemic Type Aftershock Sequence (ETAS) models are frequently used for forecasting the spatio-temporal evolution of seismicity in the short-term. We propose robust forecasting of seismicity based on ETAS model, by exploiting the link between Bayesian inference and Markov Chain Monte Carlo Simulation. The methodology considers the uncertainty not only in the model parameters, conditioned on the available catalogue of events occurred before the forecasting interval, but also the uncertainty in the sequence of events that are going to happen during the forecasting interval. We demonstrate the methodology by retrospective early forecasting of seismicity associated with the 2016 Amatrice seismic sequence activities in central Italy. We provide robust spatio-temporal short-term seismicity forecasts with various time intervals in the first few days elapsed after each of the three main events within the sequence, which can predict the seismicity within plus/minus two standard deviations from the mean estimate within the few hours elapsed after the main event.
Hossein Ebrahimian; Fatemeh Jalayer. Robust seismicity forecasting based on Bayesian parameter estimation for epidemiological spatio-temporal aftershock clustering models. Scientific Reports 2017, 7, 9803 -9803.
AMA StyleHossein Ebrahimian, Fatemeh Jalayer. Robust seismicity forecasting based on Bayesian parameter estimation for epidemiological spatio-temporal aftershock clustering models. Scientific Reports. 2017; 7 (1):9803-9803.
Chicago/Turabian StyleHossein Ebrahimian; Fatemeh Jalayer. 2017. "Robust seismicity forecasting based on Bayesian parameter estimation for epidemiological spatio-temporal aftershock clustering models." Scientific Reports 7, no. 1: 9803-9803.
It is desirable that nonlinear dynamic analyses for structural fragility assessment are performed using unscaled ground motions. The widespread use of a simple dynamic analysis procedure known as Cloud Analysis, which uses unscaled records and linear regression, has been impeded by its alleged inaccuracies. This paper investigates fragility assessment based on Cloud Analysis by adopting, as the performance variable, a scalar demand to capacity ratio that is equal to unity at the onset of limit state. It is shown that the Cloud Analysis, performed based on a careful choice of records, leads to reasonable and efficient fragility estimates. There are 2 main rules to keep in mind for record selection: to make sure that a good portion of the records leads to a demand to capacity ratio greater than unity and that the dispersion in records' seismic intensity is considerable. An inevitable consequence of implementing these rules is that one often needs to deal with the so-called collapse cases. To formally consider the collapse cases, a 5-parameter fragility model is proposed that mixes the simple regression in the logarithmic scale with logistic regression. The joint distribution of fragility parameters can be obtained by adopting a Markov Chain Monte Carlo simulation scheme leading directly to the fragility and its confidence intervals. The resulting fragility curves compare reasonably with those obtained from the Incremental Dynamic Analysis and Multiple Stripe Analysis with (variable) conditional spectrum–compatible suites of records at different intensity levels for 3 older reinforced concrete frames with shear-, shear-flexure-, and flexure-dominant behavior.
Fatemeh Jalayer; Hossein Ebrahimian; Andrea Miano; Gaetano Manfredi; Halil Sezen. Analytical fragility assessment using unscaled ground motion records. Earthquake Engineering & Structural Dynamics 2017, 46, 2639 -2663.
AMA StyleFatemeh Jalayer, Hossein Ebrahimian, Andrea Miano, Gaetano Manfredi, Halil Sezen. Analytical fragility assessment using unscaled ground motion records. Earthquake Engineering & Structural Dynamics. 2017; 46 (15):2639-2663.
Chicago/Turabian StyleFatemeh Jalayer; Hossein Ebrahimian; Andrea Miano; Gaetano Manfredi; Halil Sezen. 2017. "Analytical fragility assessment using unscaled ground motion records." Earthquake Engineering & Structural Dynamics 46, no. 15: 2639-2663.
A wide area around the town of Naples is mantled by shallow unsaturated volcanoclastic soils that are highly susceptible to fast rainfall-induced flow-like landslides. Some casualties and huge damage recorded in the last twenty years testify the serious threat posed by such events. Due to the impact of these phenomena, the local research community is strongly committed in studies whose results have allowed to understand some key aspects of the triggering and propagation mechanisms. However, the way to run for risk mitigation is still long: given the density of population and of infrastructure, the setting up of reliable early warning systems would be a fundamental tool to this aim. Based on a rich data-base about the features of the rainfall-induced landslides in unsaturated volcanoclastic soils occurred on January, 10th, 1997, in a small area located in the Sorrento peninsula, and the history of precipitations occurred in the same area in the last fifty years, the paper examines the relation between rainstorms and landslides, showing the fundamental role of the recent precipitation history.
Luca Comegna; Melania De Falco; Fatemeh Jalayer; Luciano Picarelli; Antonio Santo. The Role of the Precipitation History on Landslide Triggering in Unsaturated Pyroclastic Soils. Advancing Culture of Living with Landslides 2017, 307 -313.
AMA StyleLuca Comegna, Melania De Falco, Fatemeh Jalayer, Luciano Picarelli, Antonio Santo. The Role of the Precipitation History on Landslide Triggering in Unsaturated Pyroclastic Soils. Advancing Culture of Living with Landslides. 2017; ():307-313.
Chicago/Turabian StyleLuca Comegna; Melania De Falco; Fatemeh Jalayer; Luciano Picarelli; Antonio Santo. 2017. "The Role of the Precipitation History on Landslide Triggering in Unsaturated Pyroclastic Soils." Advancing Culture of Living with Landslides , no. : 307-313.
The frequency and severity of natural catastrophes have increased significantly over the last few years, with countries around the world having to face huge economic and human losses. Italy in particular is very seismic-prone, being located in the precise area of convergence between the African and Eurasian lithospheric plates. In addition, most Italian cities are densely populated and have many old and historical buildings, making the country even more exposed and vulnerable in terms of potential losses. Recently, new regulations gave householders the chance to buy insurance against earthquakes. Unfortunately, the widespread risk perception in Italy is very low among the population. In addition, insurance premiums can be extremely high given the low-probability-high-risk of cash flow and insolvency problems potentially incurred by an insurance company if there is a high magnitude earthquake. The aim of the methodology proposed in this paper is to give insurers an engineering instrument with which to quantify expected losses in the case of an earthquake. This will enable insurance companies to model innovative and more affordable financial products by optimizing the quantification of premiums. Seismic events with a magnitude greater than 4 from 217 a.C. to 2012 have been selected from the historical catalogue of the National Institute of Geophysics and Volcanology, and statistical simulations of earthquake scenarios are performed for each of them. In particular, the peak ground acceleration is simulated, based on the ground motion prediction equation of Bindi et al. (Bull Earthq Eng 7(3):591–608, 2009). Actual exposure is assumed for the Italian building stock, which is modelled according to the database of the National Institute of Statistics. Finally, in order to compute the total losses for the entire national building stock, the annual expected losses are quantified according to the procedure demonstrated in Asprone et al. (Struct Saf 44:70–79, 2013).
Anna Bozza; Domenico Asprone; Fatemeh Jalayer; Gaetano Manfredi. National-level prediction of expected seismic loss based on historical catalogue. Bulletin of Earthquake Engineering 2017, 15, 2853 -2877.
AMA StyleAnna Bozza, Domenico Asprone, Fatemeh Jalayer, Gaetano Manfredi. National-level prediction of expected seismic loss based on historical catalogue. Bulletin of Earthquake Engineering. 2017; 15 (7):2853-2877.
Chicago/Turabian StyleAnna Bozza; Domenico Asprone; Fatemeh Jalayer; Gaetano Manfredi. 2017. "National-level prediction of expected seismic loss based on historical catalogue." Bulletin of Earthquake Engineering 15, no. 7: 2853-2877.
Andrea Miano; Halil Sezen; Fatemeh Jalayer; Andrea Prota; Manolis Papadrakakis; M. Fragiadakis. PERFORMANCE-BASED COMPARISON OF DIFFERENT RETROFIT METHODS FOR REINFORCED CONCRETE SRUCTURES. Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015) 2017, 1515 -1535.
AMA StyleAndrea Miano, Halil Sezen, Fatemeh Jalayer, Andrea Prota, Manolis Papadrakakis, M. Fragiadakis. PERFORMANCE-BASED COMPARISON OF DIFFERENT RETROFIT METHODS FOR REINFORCED CONCRETE SRUCTURES. Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015). 2017; ():1515-1535.
Chicago/Turabian StyleAndrea Miano; Halil Sezen; Fatemeh Jalayer; Andrea Prota; Manolis Papadrakakis; M. Fragiadakis. 2017. "PERFORMANCE-BASED COMPARISON OF DIFFERENT RETROFIT METHODS FOR REINFORCED CONCRETE SRUCTURES." Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015) , no. : 1515-1535.
Andrea Miano; Fatemeh Jalayer; Andrea Prota; Manolis Papadrakakis; M. Fragiadakis. CONSIDERING STRUCTURAL MODELLING UNCERATINTIES USING BAYESIAN CLOUD ANALYSIS. Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015) 2017, 1 .
AMA StyleAndrea Miano, Fatemeh Jalayer, Andrea Prota, Manolis Papadrakakis, M. Fragiadakis. CONSIDERING STRUCTURAL MODELLING UNCERATINTIES USING BAYESIAN CLOUD ANALYSIS. Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015). 2017; ():1.
Chicago/Turabian StyleAndrea Miano; Fatemeh Jalayer; Andrea Prota; Manolis Papadrakakis; M. Fragiadakis. 2017. "CONSIDERING STRUCTURAL MODELLING UNCERATINTIES USING BAYESIAN CLOUD ANALYSIS." Proceedings of the 6th International Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (COMPDYN 2015) , no. : 1.
In an attempt to do a back analysis of the damages caused to a nineteenth century masonry structure due to the October 2009 flash flood/debris flow event in Scaletta Zanclea, the flood discharge hydrograph is reconstructed in the ungauged conditions. The hydrograph for the solid discharge is then estimated by scaling up the liquid volume to the estimated debris volume. The debris flow diffusion is simulated by solving the differential equations for a single-phase 2D flow employing triangular mesh elements, taking into account also the channelling of the flow through the buildings. The damage to the building is modelled, based on the maximum hydraulic actions caused by the debris flow, using 2D finite shell elements to model the building, boundary conditions provided by the openings, floor slab, orthogonal wall panels, and the foundation. The reconstruction of the event and the damages to the case-study building confirms the location of the damages induced by the event.
Hossein Soleimankhani; Stefano Carozza; Giuseppe T. Aronica; Fatemeh Jalayer; Antonino Recupero. Analytic Back Calculation of Debris Flow Damage Incurred to a Masonry Building: The Case of Scaletta Zanclea 2009 Event. E3S Web of Conferences 2016, 7, 04007 .
AMA StyleHossein Soleimankhani, Stefano Carozza, Giuseppe T. Aronica, Fatemeh Jalayer, Antonino Recupero. Analytic Back Calculation of Debris Flow Damage Incurred to a Masonry Building: The Case of Scaletta Zanclea 2009 Event. E3S Web of Conferences. 2016; 7 ():04007.
Chicago/Turabian StyleHossein Soleimankhani; Stefano Carozza; Giuseppe T. Aronica; Fatemeh Jalayer; Antonino Recupero. 2016. "Analytic Back Calculation of Debris Flow Damage Incurred to a Masonry Building: The Case of Scaletta Zanclea 2009 Event." E3S Web of Conferences 7, no. : 04007.
Calculating the limit state (LS) exceedance probability for a structure considering the main seismic event and the triggered aftershocks (AS) is complicated both by the time-dependent rate of aftershock occurrence and also by the cumulative damage caused by the sequence of events. Taking advantage of a methodology developed previously by the authors for post-mainshock (MS) risk assessment, the LS probability due to a sequence of mainshock and the triggered aftershocks is calculated for a given aftershock forecasting time window. The proposed formulation takes into account both the time-dependent rate of aftershock occurrence and also the damage accumulation due to the triggered aftershocks. It is demonstrated that an existing reinforced concrete moment-resisting frame with infills subjected to the main event and the triggered sequence exceeds the near-collapse LS. On the other hand, the structure does not reach the onset of near-collapse LS when the effect of triggered aftershocks is not considered. It is shown, based on simplifying assumptions, that the derived formulation yields asymptotically to the same Poisson-type functional form used when the cumulative damage is not being considered. This leads to a range of approximate solutions by substituting the fragilities calculated for intact, MS-damaged, and MS-plus-one-AS-damaged structures in the asymptotic simplified formulation. The latter two approximate solutions provide good agreement with the derived formulation. Even when the fragility of intact structure is employed, the approximate solution (considering only the time-dependent rate of aftershock occurrence) leads to higher risk estimates compared with those obtained based on only the mainshock. Copyright © 2016 John Wiley & Sons, Ltd.
Fatemeh Jalayer; Hossein Ebrahimian. Seismic risk assessment considering cumulative damage due to aftershocks. Earthquake Engineering & Structural Dynamics 2016, 46, 369 -389.
AMA StyleFatemeh Jalayer, Hossein Ebrahimian. Seismic risk assessment considering cumulative damage due to aftershocks. Earthquake Engineering & Structural Dynamics. 2016; 46 (3):369-389.
Chicago/Turabian StyleFatemeh Jalayer; Hossein Ebrahimian. 2016. "Seismic risk assessment considering cumulative damage due to aftershocks." Earthquake Engineering & Structural Dynamics 46, no. 3: 369-389.
In an attempt to conduct a back analysis of the damage caused to a 19th century masonry structure due to the October 2009 flash flood/debris flow event in Scaletta Zanclea, a flood discharge hydrograph is reconstructed in the ungauged conditions. The hydrograph for the solid discharge is then estimated by scaling up the liquid volume to the estimated debris volume. The debris flow diffusion is simulated by solving the differential equations for a single-phase two-dimensional (2D) flow that employs triangular mesh elements, also taking into account the channelling of the flow through the buildings. The damage to the building is modelled using 2D finite shell elements and is based on the maximum hydraulic action caused by the debris flow. The boundary conditions provided by the openings, floor slabs, orthogonal wall panels and the foundations are also modelled. The reconstruction of the event and the damage to the case-study building confirm the location of the damage induced by the event
Fatemeh Jalayer; Giuseppe T. Aronica; Antonino Recupero; Stefano Carozza; Gaetano Manfredi. Debris flow damage incurred to buildings: an in situ back analysis. Journal of Flood Risk Management 2016, 11, S646 -S662.
AMA StyleFatemeh Jalayer, Giuseppe T. Aronica, Antonino Recupero, Stefano Carozza, Gaetano Manfredi. Debris flow damage incurred to buildings: an in situ back analysis. Journal of Flood Risk Management. 2016; 11 ():S646-S662.
Chicago/Turabian StyleFatemeh Jalayer; Giuseppe T. Aronica; Antonino Recupero; Stefano Carozza; Gaetano Manfredi. 2016. "Debris flow damage incurred to buildings: an in situ back analysis." Journal of Flood Risk Management 11, no. : S646-S662.
Valeria Licata; Giovanni Forte; Anna D’Onofrio; Lorenza Evangelista; Fatemeh Jalayer; Antonio Santo; Francesco Silvestri. Microzonation Study on the Western Area of Napoli. Procedia Engineering 2016, 158, 511 -516.
AMA StyleValeria Licata, Giovanni Forte, Anna D’Onofrio, Lorenza Evangelista, Fatemeh Jalayer, Antonio Santo, Francesco Silvestri. Microzonation Study on the Western Area of Napoli. Procedia Engineering. 2016; 158 ():511-516.
Chicago/Turabian StyleValeria Licata; Giovanni Forte; Anna D’Onofrio; Lorenza Evangelista; Fatemeh Jalayer; Antonio Santo; Francesco Silvestri. 2016. "Microzonation Study on the Western Area of Napoli." Procedia Engineering 158, no. : 511-516.