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265 results on '"Akkar, Sinan"'

52. Drift estimates in frame buildings subjected to near-fault ground motions

Author

Akkar, Sinan, Yazgan, Ufuk, and Gulkan, Polat

Subjects
Structural engineering -- Analysis, Mathematical statistics, Engineering and manufacturing industries, Science and technology
Abstract

A simple procedure to estimate the local displacement demands in regular flame-type structures that respond in elastic limits is described. Given the spectral displacement and beam-to-column stiffness ratio, the procedure estimates the maximum ground story and maximum interstory drifts along the height of the structure. A total of 145 near-fault ground motions recorded on dense-to-firm soil sites are used for the evaluation of the procedure. The approximate drift demands computed from this procedure and the exact results from 27,550 response history analyses are used for calculating the error statistics. The calculations show that the procedure can be used with confidence for flames with fundamental periods between 0.3 and 1.5 s when they are subjected to near-fault records without pulse. The approximations are in good agreement with the exact response history results of near-fault records with pulse when lhe fundamental period to pulse period ratio is less than 1.5. The performance of the new procedure is also compared with other approximate methods that are employed for similar purposes. The method can be useful for preliminary design of new structures or rapid assessment of existing buildings. DOI: 10.1061/(ASCE)0733-9445(2005) 131:7(1014) CE Database subject headings: Accuracy: Drift: Dynamic structural analysis: Structural models: Seismic design; Statistical analysis: Regression analysis.

Published
2005

53. Statistical evaluation of approximate methods for estimating maximum deformation demands on existing structures

Author

Akkar, Sinan D. and Miranda, Eduardo

Subjects
Structural engineering -- Research, Engineering and manufacturing industries, Science and technology
Abstract

A statistical study is presented to evaluate the accuracy of five approximate methods that have been proposed in the past to estimate the maximum inelastic deformation demand on existing structures. Three are based on equivalent linearization in which the inelastic deformation is approximated by the maximum deformation of an equivalent linear elastic system having lower lateral stiffness and larger viscous damping with respect to the preyielding properties of the inelastic system. In the equivalent linear methods evaluated here the equivalent period and equivalent damping ratio are computed as a function of the maximum deformation through the displacement ductility ratio. The other two methods estimate the maximum inelastic deformation of a system by modifying its maximum elastic deformation through a displacement modification factor. Modification factors depend on the initial period of vibration and its lateral strength. A relatively large number of earthquake ground motions recorded on sites having average shear wave velocities higher than 180 m/s are used to calculate error statistics. For each method mean errors and standard errors, as well as probability of underestimating or overestimating inelastic deformations, are presented and discussed. DOI: 10.1061/(ASCE)0733-9445(2005)131:1(160) CE Database subject headings: Structural analysis; Accuracy; Approximation methods; Deformation; Nonlinear analysis; Performance evaluation; Seismic analysis; Statistical analysis.

Published
2005

54. Dynamic instability of simple structural systems

Author

Miranda, Eduardo and Akkar, Sinan D.

Subjects
Oscillators (Electronics) -- Testing, Earthquake engineering, Engineering and manufacturing industries, Science and technology
Abstract

Lateral strengths required to avoid dynamic instability of single-degree-of-freedom systems are examined. Oscillators with a bilinear hysteretic behavior with negative postyield stiffness are considered. Mean lateral strengths normalized by the lateral strength required to maintain the system elastic are computed for systems with periods ranging from 0.2 to 3.0 s when subjected to 72 earthquake ground motions recorded on firm soil. The effect of the period of vibration and postyield stiffness are investigated. Results indicate that mean normalized lateral strengths required to avoid dynamic instability decrease as negative postyield stiffness increases and that the reductions are much larger for small negative postyield stiffness than for severe negative postyield stiffnesses. It is concluded that there is a significant influence of the period of vibration for short-period systems and for systems with mildly negative postyield stiffnesses. Dispersion of normalized lateral strengths required to avoid dynamic instability are found to increase as the negative postyield stiffness decreases and as the period of vibration increases. Simple equations that capture the effects of period and postyield stiffness to aid in the evaluation of existing structures are obtained through nonliner regression analyses. CE Database subject headings: Lateral forces; Seismic effects; Structural stability; Collapse; Dynamic stability; Hysteretic systems; Regression analysis.

Published
2003

58. A New Formulation For A Code-Based Vertical Design Spectrum

Author

Kale, Ozkan and Akkar, Sinan

Abstract

Consideration of vertical seismic design loads is important for long-span structural systems, short-period structures, and for some nonstructural components in the buildings. To this end, seismic design codes utilize alternative approaches to define vertical design spectrum at different levels of complexity: either as a fraction of horizontal design spectrum or using a separate functional form having features different than the horizontal spectrum. In all cases, a consistency between the horizontal and vertical design spectral ordinates is sought. In this paper, we consider a set of modern seismic design codes, horizontal and vertical ground-motion datasets, as well as ground-motion predictive models (GMPMs) to assess the accuracy of code-based vertical design spectrum expressions. We compute horizontal and vertical spectra for different earthquake scenarios (magnitude-distance-soil condition combinations) from the selected horizontal and vertical GMPMs for comparisons with their code-based (idealized) counterparts. Besides that, we study the vertical spectrum behavior from observed ground-motion data. Our observations suggest that the vertical design spectrum formulations by current codes do not fully explain the actual vertical spectral acceleration trends. We discuss the possible reasons behind the misrepresentation of vertical spectrum by the current code approach and introduce our own expressions to compute horizontal spectrum consistent vertical design spectrum from a comprehensive simulated dataset of correlated vertical and horizontal spectral ordinates.

Published
2020

59. A risk-based multi-level stress test methodology: application to six critical non-nuclear infrastructures in Europe

Author

Argyroudis, Sotirios A., primary, Fotopoulou, Stavroula, additional, Karafagka, Stella, additional, Pitilakis, Kyriazis, additional, Selva, Jacopo, additional, Salzano, Ernesto, additional, Basco, Anna, additional, Crowley, Helen, additional, Rodrigues, Daniela, additional, Matos, José P., additional, Schleiss, Anton J., additional, Courage, Wim, additional, Reinders, Johan, additional, Cheng, Yin, additional, Akkar, Sinan, additional, Uçkan, Eren, additional, Erdik, Mustafa, additional, Giardini, Domenico, additional, and Mignan, Arnaud, additional

Published
2019
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60. Current Challenges and Future Trends in Analytical Fragility and Vulnerability Modeling

Author

Silva, Vitor, primary, Akkar, Sinan, additional, Baker, Jack, additional, Bazzurro, Paolo, additional, Castro, José Miguel, additional, Crowley, Helen, additional, Dolsek, Matjaz, additional, Galasso, Carmine, additional, Lagomarsino, Sergio, additional, Monteiro, Ricardo, additional, Perrone, Daniele, additional, Pitilakis, Kyriazis, additional, and Vamvatsikos, Dimitrios, additional

Published
2019
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65. Toward a ground-motion logic tree for probabilistic seismic hazard assessment in Europe

Author

Delavaud, Elise, Cotton, Fabrice, Akkar, Sinan, Scherbaum, Frank, Danciu, Laurentiu, Beauval, Céline, Drouet, Stéphane, Douglas, John, Basili, Roberto, Sandikkaya, M., Segou, Margaret, Faccioli, Ezio, Theodoulidis, Nikos, Delavaud, Elise, Cotton, Fabrice, Akkar, Sinan, Scherbaum, Frank, Danciu, Laurentiu, Beauval, Céline, Drouet, Stéphane, Douglas, John, Basili, Roberto, Sandikkaya, M., Segou, Margaret, Faccioli, Ezio, and Theodoulidis, Nikos

Abstract

The Seismic Hazard Harmonization in Europe (SHARE) project, which began in June 2009, aims at establishing new standards for probabilistic seismic hazard assessment in the Euro-Mediterranean region. In this context, a logic tree for ground-motion prediction in Europe has been constructed. Ground-motion prediction equations (GMPEs) and weights have been determined so that the logic tree captures epistemic uncertainty in ground-motion prediction for six different tectonic regimes in Europe. Here we present the strategy that we adopted to build such a logic tree. This strategy has the particularity of combining two complementary and independent approaches: expert judgment and data testing. A set of six experts was asked to weight pre-selected GMPEs while the ability of these GMPEs to predict available data was evaluated with the method of Scherbaum et al. (Bull Seismol Soc Am 99:3234-3247, 2009). Results of both approaches were taken into account to commonly select the smallest set of GMPEs to capture the uncertainty in ground-motion prediction in Europe. For stable continental regions, two models, both from eastern North America, have been selected for shields, and three GMPEs from active shallow crustal regions have been added for continental crust. For subduction zones, four models, all non-European, have been chosen. Finally, for active shallow crustal regions, we selected four models, each of them from a different host region but only two of them were kept for long periods. In most cases, a common agreement has been also reached for the weights. In case of divergence, a sensitivity analysis of the weights on the seismic hazard has been conducted, showing that once the GMPEs have been selected, the associated set of weights has a smaller influence on the hazard

Published
2018

66. EUROCODES: BACKGROUND & APPLICATIONS: Elaboration of maps for climatic and seismic actions for structural design with the Eurocodes

Author

FORMICHI Paolo, DANCIU Laurentiu, AKKAR Sinan, KALE Özkan, MALAKATAS Nikolaos, CROCE Pietro, NIKOLOV Dimitar, GOCHEVA Anelia, LUECHINGER Paul, FARDIS Michael, YAKUT Ahmet, APOSTOLSKA Roberta, RAPOSO DE M. DO N. E S. DE SOTTO MAYOR MARIA LUISA, DIMOVA Silvia, PINTO VIEIRA Artur, RAJČIĆ Vlatka, APOSTOLSKA Roberta, RAPOSO DE M. DO N. E S. DE SOTTO MAYOR MARIA LUISA, DIMOVA Silvia, and PINTO VIEIRA Artur

Abstract

Activities for promotion of policies for sustainable construction in the Balkan region Guidance for countries adopting the Eurocodes State-of-the-art material to elaborate maps for seismic and climatic actions for structural design Experience of the non-EU Balkan countries on elaboration of these maps, JRC.E.4-Safety and Security of Buildings

Published
2016

67. TÜRKİYE SİSMOTEKTONİK HARİTASI (SEISMOTECTONIC MAP OF TURKEY)

Author

Duman, Tamer Y., Çan, Tolga, Emre, Ömer, F. Tuba Kadirioğlu, Baştürk, Nilay Başarır, Tuğbay Kılıç, Arslan, Selim, Özalp, Selim, Kartal, Recai F., Doğan Kalafat, Karakaya, Ferdane, Azak, Tuba Eroğlu, Özel, Nurcan M., Ergintav, Semih, Akkar, Sinan, Yıldız Altınok, Tekin, Senem, Cingöz, Ayhan, and A. İhsan Kurt

Published
2016
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68. Guidelines for stress-test design for non-nuclear critical infrastructures and systems: Applications: STREST Reference Report 5

Author

AKKAR Sinan, ARGYROUDIS Sotiris, BABIČ Anže, BASCO Anna, BASILI Roberto, BRIZUELA Beatriz, CHENG Ying, COURAGE Wim, CROWLEY Helen, DOLŠEK Matjaž, ERDIK Mustafa, ESPOSITO Simona, FOTOPOULOU Stavroula, GIARDINI Domenico, IQBAL Sarfraz, KARAFAGKA Stella, LORITO Stefano, MATOS José Pedro, PIATANESI Alessio, REINDERS Johan, RODRIGUES Daniela, ROMANO Fabrizio, SALZANO Ernesto, SCHLEISS Anton J., SELVA Jacopo, STOJADINOVIĆ Bozidar, TONINI Roberto, UÇKAN Eren, VOLPE Manuela, MIGNAN Arnaud, PITILAKIS Kyriazis, and TSIONIS Georgios

Abstract

In the context of the STREST project, an engineering multi-level risk-based methodology to stress test critical non-nuclear infrastructures, named ST@STREST, has been developed. This reference report summarizes ST@STREST framework and its exploratory application to six key representative Critical Infrastructures (CIs) in Europe, exposed to variant hazards, namely: a petrochemical plant in Milazzo, Italy, large dams of the Valais region in Switzerland, hydrocarbon pipelines in Turkey, the Gasunie national gas storage and distribution network in Holland, the port infrastructure of Thessaloniki, Greece and an industrial district in the region of Tuscany, Italy. According to the characteristics of each case study, different stress test levels were applied. The application to the selected CIs is presented following the workflow of ST@STREST, comprised of four phases: Pre-Assessment phase; Assessment phase; Decision phase; and Report phase. First the goals, the method, the time frame, and the appropriate stress test level to apply are defined. Then, the stress test is performed at component and system levels and the outcomes are checked and compared to the acceptance criteria. A stress test grade is assigned and the global outcome is determined by employing a grading system. Finally, critical events and risk mitigation strategies are formulated and reported to stakeholders and authorities., JRC.E.4-Safety and Security of Buildings

Published
2016

69. Guidelines for harmonized hazard assessment for LP-HC events: STREST Reference Report 2

Author

ABSPOEL-BUKMAN Linda, AKKAR Sinan, ARISTIZABAL Claudia, BARD Pierre-Yves, BEAUVAL Céline, CHENG Ying, COURAGE Wim, CROWLEY Helen, ERDIK Mustafa, FOTOPOULOU Stavroula, GIARDINI Domenico, HOLLENDER Fabrice, KARAFAGKA Stella, KOTHA Sreeram Reddy, IQBAL Sarfraz, MANAKOU Maria, MARZOCCHI Warmer, MIRAGLIA Simona, PITILAKIS Kyriazis, RIEDEL Ismaël, SELVA Jacopo, SMERZINI Chiara, TARONI Matteo, UÇKAN Eren, WEATHERILL Graeme, MIGNAN Arnaud, COTTON Fabrice, GUÉGUEN Philippe, and TSIONIS Georgios

Abstract

This report describes the main conclusions of the STREST project (and associated guidelines) to evaluate hazard of Low-Probability High-Consequences (LP-HC) events used to define stress tests for non-nuclear Critical Infrastructures (CIs). Several new approaches have been developed to assess these extreme hazard scenarios and to evaluate the associated uncertainties. This report presents a summary of the developments, results and products issued from Work Package 3 (WP3) of STREST. It is given as a set of “recommendations” for potential users responsible of the estimation of hazard for a particular non-nuclear CI in the European Union and other countries. The methods and guidelines are dedicated to two different target-users: project managers and hazard experts. It poses the main differences with a traditional Probabilistic Hazard Assessment analysis, the benefits and extra challenges, and the particular information requirements for the three selected infrastructure classes covered in STREST. In a simple and understandable manner, it summarizes the principal available tools, the main references and the application examples issued from the project in order to help the users in the realization of theirs studies., JRC.E.4-Safety and Security of Buildings

Published
2016

71. Çizgisel ve Mekansal Düzleştirilmiş Sismik Kaynak Model Kullanılarak Türkiye Olasılıksal Deprem Tehlike Analizi

Author

Çan, Tolga, Tekin, Senem, Demircioğlu, Mine, Şeşetyan, Karin, Duman, Tamer Yiğit, Ergintav, Semih, Akkar, Sinan, Çukurova Üniversitesi, Mühendislik Fakültesi, Jeoloji Mühendisliği Bölümü, Çan, Tolga, and Tekin, Senem

Subjects
Deprem Tehlikesi ve Senaryoları, Earthquake Hazard and Scenarios
Abstract

Türkiye ve çevresindeki yoğun sismik aktivite, güncel levha hareketleri etkisi altında gelişmiş çok sayıda levha içi aktif faylar, transform fay sistemleri ve dalma-batma kuşağı gibi ana tektonik yapılar tarafından kontrol edilmektedir. Bölgedeki deprem tehlikesi daha önce birçok çalışmada farklı yöntemlerle ele alınmıştır. Ancak, deprem tehlike hesaplamalarına ilişkin son yıllarda geliştirilen yeni yaklaşımlar ile hesaplamalarda kullanılan temel parametrelerinden ulusal dirifay veri tabanı ve aletsel deprem kataloğunun yenilenmesi, beraberinde Türkiye deprem haritalarının da güncellenmesi ihtiyacını ortaya çıkarmıştır. Bu kapsamda, Ulusal Deprem Stratejisi ve Eylem Planı gereği, ulusal katılımlı proje grubunca, Türkiye Deprem Tehlike Haritaları yeniden değerlendirilmiştir. Olasılıksal deprem tehlike analizleri i-) alansal kaynak model ve ii-) çizgisel ve mekânsal olarak düzleştirilmiş sismik kaynak modelleri için ayrı ayrı ele alınmıştır. Bu çalışmada çizgisel ve mekânsal olarak düzleştirilmiş sismik kaynak modelin parametrelerinden ve modelden elde edilen sonuçlar değerlendirilmiştir. Söz konusu modellerde çizgisel sismik kaynaklar boyunca, düzlem konumları da dikkate alınarak 15-km genişliğinde kuşaklar oluşturulmuştur. Bu kuşaklar içerisinde kalan 6.0’dan büyük depremlerin doğrudan çizgisel sismik kaynak tarafından üretildiği, dışında kalan depremlerin ise mekânsal olarak düzleştirilmiş sismisiteden geldiği kabulü yapılarak deprem aktivitesi hesaplanmıştır. Mekansal düzleştirilmiş sismisite deprem kataloğunun derinlik bilgisine göre sığ ve derin olarak iki ayrı kategoriye ayrılması ve her bir kategori için tamamlılık analizlerinin yapılmasıyla hesaplanmıştır. Sonuç olarak, 50 yılda sırasıyla %50, %10 ve %2 aşılma olasılıklarına karşılık gelen 72, 475, 2475 yıllık tekarlanma aralıklarına ilişkin yer hareketi (maksimum yer ivmesi, 0.2 sn ve 1.0 sn’deki spektral ivme) dağılımları elde edilmiştir Anahtar Kelimeler: Deprem Tehlikesi ve Senaryoları The high seismic activity around Turkey is controlled by the main tectonic structures containing the active shallow crustal faults, transformed fault systems and subduction fault systems under the effect of the current plate movement. The regional hazard has been worked in a several studies with different method. Recently , new techniques used in the last years about the seismic hazard assessment has brought the necessity to review the national active fault database and compiled earthquake catalogue with turkey's hazard maps. In this concept the national earthquake strategy and plan f action are reassessed by national participation project group. The two seismic sources are modelled separately in the probabilistic earthquake hazard analysis: 1-Area source model 2- Fault and spatial smoothing seismic source model. In thıs study, we will further focus on definition and delineation of the Fault and spatial smoothing seismic source model and intrinsic uncertainty on the earthquake occurrence rates estimation. Based on the surface projection along this faut model, the buffer zone with 15km are generated. The earthquakes with magnitude greater than 6.0 are assumed to occur inside this 15 km buffer zone, the rest of the seismicty are assumed to obtain from the smoothed seismicty, and the earthquake activity are calculated according to this assumption. The depth knowledge in the seismicty database are also considering into two categories: Shallow and Deep. The completeness analysis are also computed for each of them. Finally, PSHA results obtained for the fault and spatial smoothed seismic source model wll be presented for 72, 475 and 2475 years return periods (corresponding to 50%, 10%, and 2% probability of exceedance in 50 years) according to PGA, spectral acceleration at 0.2 sec. and 1.0 sec.

Published
2015

72. RESORCE (Reference database for seismic ground motion in Europe)

Author

Traversa, Paola, Akkar, Sinan, Ameri, Gabriele, Cotton, Fabrice, Douglas, John, Frobert, Laurent, Godey, Stéphanie, HERNANDEZ, Bruno, Luzi, Lucia, Sandikkaya, M. Abdullah, Centre d'Expertise et d'Inspection dans les Domaines de la Réalisation et de l'Exploitation - Service Géologie Géotecnique (CEIDRE- TEGG), EDF (EDF), Kandilli Observatory and Earthquake Research Institute (KOERI), Boǧaziçi üniversitesi = Boğaziçi University [Istanbul], FUGRO-Geoter International, FUGRO-Geoter, Institut des Sciences de la Terre (ISTerre), Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), European Mediterranean Seismological Centre (EMSC/CSEM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA), DAM Île-de-France (DAM/DIF), Direction des Applications Militaires (DAM), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Istituto Nazionale di Geofisica e Vulcanologia – Sezione di Milano (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Middle East Technical University [Ankara] (METU), SIGMA, European Project: 226967,EC:FP7:ENV,FP7-ENV-2008-1,SHARE(2009), Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Douglas, John, Seismic Hazard Harmonization in Europe - SHARE - - EC:FP7:ENV2009-06-01 - 2012-11-30 - 226967 - VALID, and Boğaziçi University [Istanbul]

Subjects
[SDE.MCG] Environmental Sciences/Global Changes, [PHYS.PHYS.PHYS-GEO-PH] Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, seismic hazard, [SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], strong-motion records, accelerometric data, strong-motion database
Abstract

With the aim of improving seismic ground-motion models in Europe and reducing associated uncertainties, the compilation of a high-quality database of seismic-motion recordings and associated metadata is of primary importance. SIGMA research and development project, devoted to the improvement of seismic hazard estimates, methods and data for France and nearby regions, has been funding the implementation of RESORCE (Reference databaSe fOR seismiC ground-motion in Europe, Akkar et al., 2014).

Published
2014

80. Seismotectonic database of Turkey

Author

Duman, Tamer Y., primary, Çan, Tolga, additional, Emre, Ömer, additional, Kadirioğlu, F. Tuba, additional, Başarır Baştürk, Nilay, additional, Kılıç, Tuğbay, additional, Arslan, Selim, additional, Özalp, Selim, additional, Kartal, Recai F., additional, Kalafat, Doğan, additional, Karakaya, Ferdane, additional, Eroğlu Azak, Tuba, additional, Özel, Nurcan M., additional, Ergintav, Semih, additional, Akkar, Sinan, additional, Altınok, Yıldız, additional, Tekin, Senem, additional, Cingöz, Ayhan, additional, and Kurt, A. İhsan, additional

Published
2016
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82. Assessment of Aleatory and Epistemic Uncertainty for Ground-Motion Intensity Measure Prediction in Turkey.

Author

Çağnan, Zehra and Akkar, Sinan

Abstract

In this study, we quantify the reduction in total sigma (⁠σtotal⁠) of the Turkish ground-motion predictive models by partially removing the ergodic assumption. By partitioning residuals into four components: repeatable source-specific and site-specific deviations from the population mean as well as site-corrected within-event and source-corrected between-event parts, event-corrected single-station standard deviation (⁠ϕss⁠) and source-corrected between-event standard deviation (⁠τss⁠) models were derived. With site correction, σtotal was shown to reduce by 15%. With source correction as well, σtotal was shown to reduce by a further 15% at short- and long-period ranges. The developed aleatory variability models are recommended to be used in hazard assessment studies of single sites under the dominant effect of the North Anatolian fault zone. Last but not least, we quantify the total ground-motion variability by computing the model-to-model variability and statistical-error components of epistemic uncertainty corresponding to two recent probabilistic seismic hazard assessment efforts for Turkey. [ABSTRACT FROM AUTHOR]

Published
2019
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83. Compilation and critical review of GMPEs for the GEM-PEER Global GMPEs Project

Author

Douglas, John, Cotton, Fabrice, Di Alessandro, Carola, Boore, David M., Abrahamson, N.A., Akkar, Sinan, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institut des Sciences de la Terre (ISTerre), Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Pacific Earthquake Engineering Research Center (PEER), Department of Mathematics [Berkeley], University of California [Berkeley], University of California-University of California-University of California [Berkeley], University of California-University of California, United States Geological Survey [Reston] (USGS), Pacific Earthquake Engineering Research Center, Middle East Technical University [Ankara] (METU), This study was funded by the GEM Foundation as part of the Pacific Earthquake Engineering Research Center's (PEER's) Global GMPEs project., GEM Global GMPEs, Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC)-University of California [Berkeley] (UC Berkeley), and University of California (UC)-University of California (UC)

Subjects
ground motion prediction equations, seismic hazard assessment, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, tectonic regionalization, attenuation relations, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Global Earthquake Model
Abstract

International audience; Ground-motion prediction equations (GMPEs) relate a ground-motion parameter (e.g. peak ground acceleration, PGA) to a set of explanatory variables describing the source, wave propagation path and site conditions. In the past five decades many hundreds of GMPEs for the prediction of PGA and linear elastic response spectral ordinates have been published. We discuss the pre-selection of GMPEs undertaken within the framework of the GEM-PEER Global GMPEs Project. The pre-selection criteria adopted were consistent with the current state-of-the-art in ground-motion characterization and sought to retain only the most robust GMPEs. Consideration of broad tectonic regionalization (e.g. shallow crustal seismicity in tectonically-active areas, stable continental regions and subduction zones) was made but it was assumed (based on previous studies) that strong regional differences were not present within these tectonic classes. In total about thirty GMPEs were pre-selected for closer inspection and testing to obtain a final set of ground-motion models.

Published
2012

84. Defining a consistent strategy to model ground-motion parameters for the GEM-PEER Global GMPEs project

Author

Akkar, Sinan, Douglas, John, Di Alessandro, Carola, Campbell, Kenneth, Somerville, Paul, Cotton, Fabrice, Silva, Walt, Baker, Jack, Middle East Technical University [Ankara] (METU), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Pacific Earthquake Engineering Research Center (PEER), Department of Mathematics [Berkeley], University of California [Berkeley], University of California-University of California-University of California [Berkeley], University of California-University of California, EQECAT Inc., URS Corporation, Institut des Sciences de la Terre (ISTerre), Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry]), Pacific Engineering and Analysis, Department of Civil and Environmental Engineering [Stanford] (CEE), Stanford University, This study was funded by the GEM Foundation as part of the Pacific Earthquake Engineering Research Center's (PEER's) Global GMPEs project., GEM Global GMPEs, University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC)-University of California [Berkeley] (UC Berkeley), University of California (UC)-University of California (UC), and Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)

Subjects
predictor parameters of GMPEs, seismic hazard assessment, [SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, Ground-motion prediction equations (GMPEs), [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], Physics::Geophysics
Abstract

International audience; The project entitled Global Ground Motion Prediction Equations is funded by the Global Earthquake Model (GEM) Foundation and has the objective of recommending a harmonized suite of ground motion prediction equations (GMPEs) that can be used at the global and regional scales for seismic hazard analysis and loss estimation studies. As part of this project, Task 1a experts were commissioned to make recommendations on the critical aspects of seismological predictor parameters that are used by predictive model developers to estimate ground motions for different earthquake scenarios. It is hoped that these recommendations would lead to the optimum description of ground-motion models that can be used efficiently for reliable seismic hazard assessment studies.

Published
2012

85. Toward New Single-Station Sigma Models

Author

Rodriguez-Marek, Adrian, Cotton, Fabrice, Abrahamson, N., Akkar, Sinan, Al-Atik, Linda, Anderson, John, Bonilla, Luis Fabian, Bommer, Julian J., Bungum, Hilmar, Douglas, John, Drouet, Stéphane, Edwards, Benjamin, Faeh, Donat, Montalva, G. A., Dawood, H., Renault, Philippe, Scherbaum, Frank, Strasser, Fleur, Virginia Tech [Blacksburg], Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Pacific Gas and Electric Company, Middle East Technical University [Ankara] (METU), Department of Mathematics [Berkeley], University of California [Berkeley], University of California-University of California, University of Nevada [Reno], Laboratoire des Ponts et Chaussées, Département Géotechnique, Eau et Risques, Department of Civil and Environmental Engineering [Imperial College London], Imperial College London, International Centre for Geohazards, NORSAR, Norwegian Seismic Array (NORSAR), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Risques, Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), Institute of Geophysics [ETH Zürich], Department of Earth Sciences [ETH Zürich] (D-ERDW), Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich)-Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology in Zürich [Zürich] (ETH Zürich), Civil and Environmental Engineering Department, Washington State University (WSU), Department of Civil Engineering, Universidad de Concepción [Chile], SwissNuclear, PEGASOS Refinement Project, Institute Geowissenschaften, Universität Potsdam, Council for Geoscience, Seismology unit, Université Joseph Fourier - Grenoble 1 (UJF)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-PRES Université de Grenoble-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS), Risques (Risques), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Laboratoire Central des Ponts et Chaussées (LCPC)-Centre National de la Recherche Scientifique (CNRS)-Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Laboratoire Central des Ponts et Chaussées (LCPC)-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences [Swiss Federal Institute of Technology - ETH Zürich] (D-ERDW), and Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)- Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich)

Subjects
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]
Abstract

Single-station sigma values for more than 600 stations have been computed using the same method for all records and datasets from different tectonic regions (California, Taiwan, Japan, Turkey, Mexico, Switzerland and France). This work has been driven by the need to develop better estimates of standard deviation for non-ergodic probabilistic seismic hazard assessment in Switzerland (PEGASOS Refinement Project), and for new ground motion models being developed for eastern North America (NGA-east) and western North America (NGA-west2). The results show that the average single-station standard deviations are lower than the ergodic values of standard deviation. Moreover, the single-station withinevent standard deviations appear to have little variability across different tectonic regions. However, there is significant variability between stations and, in some instances, values of single-station standard deviation are higher than their ergodic counterpart. This variability seems to be (on the first order) controlled by path effects, and it can be modelled by probability distribution functions. Our results also show that the Vs30 dependency is weak, while a reduction of the withinevent standard deviation is apparent with increasing distance (and magnitude). We finally amalgamate all within-event residuals from the different tectonic regions in order to propose and test several within-event single-station sigma models (constant, distance-dependent, distance and magnitude-dependent).

Published
2011

87. An updated and unified earthquake catalogue for the Western Balkan Region

Author

Markušić, Snježana, primary, Gülerce, Zeynep, additional, Kuka, Neki, additional, Duni, Llambro, additional, Ivančić, Ines, additional, Radovanović, Slavica, additional, Glavatović, Branislav, additional, Milutinović, Zoran, additional, Akkar, Sinan, additional, Kovačević, Svetlana, additional, Mihaljević, Jadranka, additional, and Šalić, Radmila, additional

Published
2015
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89. On Baseline Corrections And Uncertainty In Response Spectra For Baseline Variations Commonly Encountered In Digital Accelerograph Records

Author

Akkar, Sinan and Boore, David M.

Abstract

Most digital accelerograph recordings are plagued by long-period drifts, best seen in the velocity and displacement time series obtained from integration of the acceleration time series. These drifts often result in velocity values that are nonzero near the end of the record. This is clearly unphysical and can lead to inaccurate estimates of peak ground displacement and long-period spectral response. The source of the long-period noise seems to be variations in the acceleration baseline in many cases. These variations could be due to true ground motion (tilting and rotation, as well as local permanent ground deformation), instrumental effects, or analog-to-digital conversion. Very often the trends in velocity are well approximated by a linear trend after the strong shaking subsides. The linearity of the trend in velocity implies that no variations in the baseline could have occurred after the onset of linearity in the velocity time series. This observation, combined with the lack of any trends in the pre-event motion, allows us to compute the time interval in which any baseline variations could occur. We then use several models of the variations in a Monte Carlo procedure to derive a suite of baseline-corrected accelerations for each noise model using records from the 1999 Chi-Chi earthquake and several earthquakes in Turkey. Comparisons of the mean values of the peak ground displacements, spectral displacements, and residual displacements computed from these corrected accelerations for the different noise models can be used as a guide to the accuracy of the baseline corrections. For many of the records considered here the mean values are similar for each noise model, giving confidence in the estimation of the mean values. The dispersion of the ground-motion measures increases with period and is noise-model dependent. The dispersion of inelastic spectra is greater than the elastic spectra at short periods but approaches that of the elastic spectra at longer periods. The elastic spectra from the most basic processing, in which only the pre-event mean is removed from the acceleration time series, do not diverge from the baseline-corrected spectra until periods of 10-20 sec or more for the records studied here, implying that for many engineering purposes elastic spectra can be used from records with no baseline correction or filtering.

Published
2009

90. Probabilistic permanent fault displacement hazard via Monte Carlo simulation and its consideration for the probabilistic risk assessment of buried continuous steel pipelines.

Author

Cheng, Yin and Akkar, Sinan

Subjects
MONTE Carlo method, PIPE design & construction, EARTHQUAKE hazard analysis, EARTHQUAKE resistant design, SURFACE fault ruptures, PROBABILITY theory
Abstract

Permanent fault displacements (PFDs) because of fault ruptures emerging at the surface are critical for seismic design and risk assessment of continuous pipelines. They impose significant compressive and tensile strains to the pipe cross-section at pipe-fault crossings. The complexity of fault rupture, inaccurate mapping of fault location and uncertainties in fault-pipe crossing geometries require probabilistic approaches for assessing the PFD hazard and mitigating pipeline failure risk against PFD. However, the probabilistic approaches are currently waived in seismic design of pipelines. Bearing on these facts, this paper first assesses the probabilistic PFD hazard by using Monte Carlo-based stochastic simulations whose theory and implementation are given in detail. The computed hazard is then used in the probabilistic risk assessment approach to calculate the failure probability of continuous pipelines under different PFD levels as well as pipe cross-section properties. Our probabilistic pipeline risk computations consider uncertainties arising from complex fault rupture and geomorphology that result in inaccurate mapping of fault location and fault-pipe crossings. The results presented in this paper suggest the re-evaluation of design provisions in current pipeline design guidelines to reduce the seismic risk of these geographically distributed structural systems. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Published
2017
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95. Comparisons among the five ground-motion models developed using RESORCE for the prediction of response spectral accelerations due to earthquakes in Europe and the Middle East

Author

Douglas, John, primary, Akkar, Sinan, additional, Ameri, Gabriele, additional, Bard, Pierre-Yves, additional, Bindi, Dino, additional, Bommer, Julian J., additional, Bora, Sanjay Singh, additional, Cotton, Fabrice, additional, Derras, Boumédiène, additional, Hermkes, Marcel, additional, Kuehn, Nicolas Martin, additional, Luzi, Lucia, additional, Massa, Marco, additional, Pacor, Francesca, additional, Riggelsen, Carsten, additional, Sandıkkaya, M. Abdullah, additional, Scherbaum, Frank, additional, Stafford, Peter J., additional, and Traversa, Paola, additional

Published
2013
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96. Application of a Monte-Carlo simulation approach for the probabilistic assessment of seismic hazard for geographically distributed portfolio.

Author

Akkar, Sinan and Cheng, Yin

Subjects
MONTE Carlo method, EARTHQUAKE hazard analysis, EARTHQUAKE intensity, EMERGENCY management, STATISTICAL correlation
Abstract

The conventional integral approach is very well established in probabilistic seismic hazard assessment (PSHA). However, Monte-Carlo (MC) simulations can become an efficient and flexible alternative against conventional PSHA when more complicated factors (e.g. spatial correlation of ground shaking) are involved. This study aims at showing the implementation of MC simulation techniques for computing the annual exceedance rates of dynamic ground-motion intensity measures (GMIMs) (e.g. peak ground acceleration and spectral acceleration). We use multi-scale random field technique to incorporate spatial correlation and near-fault directivity while generating MC simulations to assess the probabilistic seismic hazard of dynamic GMIMs. Our approach is capable of producing conditional hazard curves as well. We show various examples to illustrate the potential use of the proposed procedures in the hazard and risk assessment of geographically distributed structural systems. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Published
2016
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