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2. International benchmark on numerical simulations for 1D, nonlinear site response (Prenolin): Verification phase based on canonical cases

Author

Régnier, J, Bonilla, LF, Bard, PY, Bertrand, E, Hollender, F, Kawase, H, Sicilia, D, Arduino, P, Amorosi, A, Asimaki, D, Boldini, D, Chen, L, Chiaradonna, A, Demartin, F, Ebrille, M, Elgamal, A, Falcone, G, Foerster, E, Foti, S, Garini, E, Gazetas, G, Gélis, C, Ghofrani, A, Giannakou, A, Gingery, JR, Glinsky, N, Harmon, J, Hashash, Y, Iai, S, Jeremić, B, Kramer, S, Kontoe, S, Kristek, J, Lanzo, G, Di Lernia, A, Lopez-Caballero, F, Marot, M, McAllister, G, Mercerat, ED, Moczo, P, Montoya-Noguera, S, Musgrove, M, Nieto-Ferro, A, Pagliaroli, A, Pisanò, F, Richterova, A, Sajana, S, Santisi D’avila, MP, Shi, J, Silvestri, F, Taiebat, M, Tropeano, G, Verrucci, L, and Watanabe, K

Subjects
Geochemistry & Geophysics, Geophysics, Civil Engineering
Abstract

PREdiction of NOn-LINear soil behavior (PRENOLIN) is an international benchmark aiming to test multiple numerical simulation codes that are capable of predicting nonlinear seismic site response with various constitutive models. One of the objectives of this project is the assessment of the uncertainties associated with nonlinear simulation of 1D site effects. A first verification phase (i.e., comparison between numerical codes on simple idealistic cases) will be followed by a validation phase, comparing the predictions of such numerical estimations with actual strongmotion recordings obtained at well-known sites. The benchmark presently involves 21 teams and 23 different computational codes. We present here the main results of the verification phase dealing with simple cases. Three different idealized soil profiles were tested over a wide range of shear strains with different input motions and different boundary conditions at the sediment/bedrock interface. A first iteration focusing on the elastic and viscoelastic cases was proved to be useful to ensure a common understanding and to identify numerical issues before pursuing the nonlinear modeling. Besides minor mistakes in the implementation of input parameters and output units, the initial discrepancies between the numerical results can be attributed to (1) different understanding of the expression “input motion” in different communities, and (2) different implementations of material damping and possible numerical energy dissipation. The second round of computations thus allowed a convergence of all teams to the Haskell–Thomson analytical solution in elastic and viscoelastic cases. For nonlinear computations, we investigate the epistemic uncertainties related only to wave propagation modeling using different nonlinear constitutive models. Such epistemic uncertainties are shown to increase with the strain level and to reach values around 0.2 (log10 scale) for a peak ground acceleration of 5 m=s2 at the base of the soil column, which may be reduced by almost 50% when the various constitutive models used the same shear strength and damping implementation.

Published
2016

6. Prenolin: International benchmark on 1D nonlinear: Site-response analysis—validation phase exercise

Author

Mecánica Aplicada, Régnier J., Bonilla L.-F., Bard P.-Y., Bertrand E., Hollender F., Kawase H., Sicilia D., Arduino P., Amorosi A., Asimaki D., Boldini D., Chen L., Chiaradonna A., Demartin F., Elgamal A., Falcone G., Foerster E., Foti S., Garini E., Gazetas G., Gélis C., Ghofrani A., Giannakou A., Gingery J., Glinsky N., Harmon J., Hashash Y., Iai S., Kramer S., Kontoe S., Kristek J., Lanzo G., Lernia A.D., Lopez-Caballero F., Marot M., McAllister G., Mercerat E.D., Moczo P., Montoya-Noguera S., Musgrove M., Nieto-Ferro A., Pagliaroli A., Passeri F., Richterova A., Sajana S., Santisi D’Avila M.P., Shi J., Silvestri F., Taiebat M., Tropeano G., Vandeputte D., Verrucci L., Mecánica Aplicada, Régnier J., Bonilla L.-F., Bard P.-Y., Bertrand E., Hollender F., Kawase H., Sicilia D., Arduino P., Amorosi A., Asimaki D., Boldini D., Chen L., Chiaradonna A., Demartin F., Elgamal A., Falcone G., Foerster E., Foti S., Garini E., Gazetas G., Gélis C., Ghofrani A., Giannakou A., Gingery J., Glinsky N., Harmon J., Hashash Y., Iai S., Kramer S., Kontoe S., Kristek J., Lanzo G., Lernia A.D., Lopez-Caballero F., Marot M., McAllister G., Mercerat E.D., Moczo P., Montoya-Noguera S., Musgrove M., Nieto-Ferro A., Pagliaroli A., Passeri F., Richterova A., Sajana S., Santisi D’Avila M.P., Shi J., Silvestri F., Taiebat M., Tropeano G., Vandeputte D., and Verrucci L.

Abstract

This article presents the main results of the validation phase of the PRENOLIN project. PRENOLIN is an international benchmark on 1D nonlinear (NL) site-response analysis. This project involved 19 teams with 23 different codes tested. It was divided into two phases; with the first phase verifying the numerical solution of these codes on idealized soil profiles using simple signals and real seismic records. The second phase described in this article referred to code validation for the analysis of real instrumented sites. This validation phase was performed on two sites (KSRH10 and Sendai) of the Japanese strong-motion networks KiK-net and Port and Airport Research Institute (PARI), respectively, with a pair of accelerometers at surface and depth. Extensive additional site characterizations were performed at both sites involving in situ and laboratory measurements of the soil properties. At each site, sets of input motions were selected to represent different peak ground acceleration (PGA) and frequency content. It was found that the code-to-code variability given by the standard deviation of the computed surface-response spectra is around 0.1 (in log10 scale) regardless of the site and input motions. This indicates a quite large influence of the numerical methods on site-effect assessment and more generally on seismic hazard. Besides, it was observed that sitespecific measurements are of primary importance for defining the input data in siteresponse analysis. The NL parameters obtained from the laboratory measurements should be compared with curves coming from the literature. Finally, the lessons learned from this exercise are synthesized, resulting also in a few recommendations for future benchmarking studies, and the use of 1D NL, total stress site-response analysis. © 2018, Seismological Society of America. All rights reserved.

Published
2021

7. Messinian canyons morphology of the Rhône and Ardèche rivers (south-east France): new insights from seismic profiles

Author

Do Couto Damien, Cushing Edward Marc, Mocochain Ludovic, Rubino Jean-Loup, Miquelis Florian, Hanot Franck, Froment Bérénice, Gélis Céline, Camus Hubert, Bagayoko Nanaba, and Bellier Olivier

Subjects
messinian salinity crisis, messinian erosional surface, seismic profiles, paleo-canyon, rhône, ardèche, Geology, QE1-996.5
Abstract

Twelve available two-way time high-resolution seismic reflection profiles located in the central part of the middle Rhône valley are interpreted. In addition, one of the profiles was reprocessed to determine the P-wave velocities of the main geological units and to convert this profile into a depth cross section. The Lower and Upper Cretaceous units are clearly identifiable on all the profiles, along with the Messinian Erosion Surface (MES) carved out during the Messinian Salinity Crisis (MSC) by the paleo-Rhône and its western tributaries, the Ardèche and Cèze paleo-canyons. The Plio-Quaternary fill of these paleo-canyons shows at least 4 main units with an overall transgression. The combination of geological data from geological maps, geological field surveys and borehole data made it possible to model the MES in 3D at the scale of the region, and to produce depth/elevation model. From a geological point of view, the interpretation of the seismic profiles enabled us to reconstruct the stages in the sub-aquatic filling of the Messinian-Pliocene aggradation of the paleo-river. Several Mass Transport Deposits (MTDs) were identified both during the drop and during the rise in the Mediterranean Sea level. From a geomorphological point of view, this study provides new insights in the route and longitudinal profile of paleo-rivers and, in particular, it deepens the profile of the Paleo-Rhône at the latitude of the Tricastin region (up to −700 m b.s.l.) and significantly modifies the course and depth of the Ardèche proposed in previous studies. The N-Ardèche river, known to develop a karstic system during the MSC, is connected to a deep canyon, most likely through a karstic pocket valley, as suggested by the very steep longitudinal profile of the MES. Finally, from a structural point of view, our interpretation of the seismic profiles shows a broad ENE-trending anticline structure associated with a normal fault which apparently did not affect the Mio-Pliocene fill. In the southern part of the area, near the Uchaux anticline, the imaged structures suggest the presence of a recent (syn- to post-Pliocene) fault propagation fold. In addition to all the new information on the geology, morphology and methods of excavation and filling of the Messinian paleo-canyon, the proposed topographic model of the paleo-canyon is crucial for modelling seismic movement in the context of a basin with a complex geometry and, in particular, for the numerical assessment of site effects in a context of low seismicity.

Published
2024
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11. Elastic full waveform inversion in the frequency domain

Author

Gélis, C., Virieux, J., Operto, S., Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Laboratoire Central des Ponts et Chaussées (LCPC)-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)-Centre National de la Recherche Scientifique (CNRS), SEISCOPE, Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-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), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), 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), and 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)

Subjects
[SDU.STU]Sciences of the Universe [physics]/Earth Sciences, ComputingMilieux_MISCELLANEOUS
Abstract

International audience

Published
2008

12. Seismic hazard on the French Riviera : new data, interpretation and simulations

Author

Courboulex, F., Larroque, C., Deschamps, Anne, Kohrs-Sansorny, C., Gélis, C., Got, J.-L., Charreau, J., Stéphan, J.-F., Béthoux, N., Virieux, J., Brunel, D., Maron, C., Duval, A.-M., Perez, J.-L., Mondielli, P., Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), 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), ERA 6 Risque sismique (ERA 6 Risque sismique - Equipe recherche associée au LCPC), Avant création Cerema, Direction environnement urbanisme et construction, Principauté de Monaco, Principauté de Monaco, Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), 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), Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Central des Ponts et Chaussées (LCPC)-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)-Centre National de la Recherche Scientifique (CNRS), Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Nice Sophia Antipolis (... - 2019) (UNS), and Université Côte d'Azur (UCA)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph], [SDE.MCG]Environmental Sciences/Global Changes, seismotectonics, [PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph], earthquake location, strong ground motion, fault tectonics, microseismicity, earthquake-source mechanism
Abstract

International audience; We present here a detailed analysis of a seismic data set recorded by a dense seismological network installed over 6 months in the southeast of France. This experiment was set-up at the boundary between the Ligurian basin and the southern subalpine thrust belt (the Nice arc), which is a complex tectonic region that undergoes low to moderate seismicity. We recorded more than 500 microearthquakes, among which 348 occurred exactly in the centre of the network during a very active seismic sequence that lasted mainly over 2 months. We performed an absolute location of all of the events and calculated the magnitudes. Then we applied a cross-correlation technique to gather similar events and to relocate relatively few of them. This method revealed a very clear alignment of 19 events in a direction N120° oblique to the N20° general trend of seismicity. Focal mechanisms were determined for the four largest events and composite solutions for 32 smaller ones. Both the alignments of the earthquakes and the focal solutions revealed that two oblique segments of the fault were activated during the crisis. The main segment (8 km long) that was oriented NNE with a left-lateral strike slip movement is called the Blausasc fault. Taking into account the tectonic evolution and the relationships between surface structures and the distribution of earthquakes, and through a paleaoreconstruction of the tectonic evolution, we propose that the Blausasc fault is the hidden root of the Peille-Laghet fault, which has a mapped length of at least 15 km. The smaller segment (0.6 km long) that was activated during the crisis could be interpreted as an antithetic Riedel fracture. The active Blausasc fault is located in a densely populated zone, at only 10 km from the crowded cities of Monaco and Nice. It is thus particularly interesting to analyse it for hazard assessment. In the last section, we present a simulation that is aimed at predicting what the ground motion in the city of Nice would be like if an earthquake of magnitude 5.7 occurs on this fault. For this, we used the recordings of the largest event of the seismic sequence (Ml= 3.2) and an empirical Green's function summation scheme to simulate the ground motion at two stations situated in urban environments. The values obtained show that especially on soft soil sites, the effects of such an earthquake would be considerable in the city of Nice.

Published
2007
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14. An Unknown active fault revealed by microseismicity in the South-East of France

Author

Courboulex, F., Larroque, C., Deschamps, Anne, Gélis, C., Charreau, J., Stéphan, J.-F., Géoazur (GEOAZUR 6526), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Université Nice Sophia Antipolis (1965 - 2019) (UNS), and COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[SDU]Sciences of the Universe [physics]
Abstract

Geophysical Research Letters, v. 30, n. 15, p. 1782, 2003. http://dx.doi.org/10.1029/2003GL017171; International audience

Published
2003
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20. Seismic hazard on the French Riviera: observations, interpretations and simulations

Author

Courboulex, F., primary, Larroque, C., additional, Deschamps, A., additional, Kohrs-Sansorny, C., additional, Gélis, C., additional, Got, J. L., additional, Charreau, J., additional, Stéphan, J. F., additional, Béthoux, N., additional, Virieux, J., additional, Brunel, D., additional, Maron, C., additional, Duval, A. M., additional, Perez, J-L., additional, and Mondielli, P., additional

Published
2007
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23. A Study on the Variability of Kappa (κ) in a Borehole: Implications of the Computation Process.

Author

Ktenidou, O.-J., Gélis, C., and Bonilla, L.-F.

Subjects
SEISMOGRAMS, EARTHQUAKES, MATHEMATICAL variables, BOREHOLES, PREDICTION models, MATHEMATICAL models
Abstract

Knowledge of the acceleration spectral shape is crucial to various applications in engineering seismology. Spectral amplitude decays rapidly at high frequencies. Anderson and Hough (1984) introduced the empirical factor κ to model this attenuation. This is the first time κ is studied in a vertical array consisting of more than two stations. We use 180 earthquakes recorded at a downhole array with five stations in soils and rock to investigate the effect of soil conditions on κ. Given that κ computation processes vary across literature when following the classic AndersonHough method, we investigate its variability with the different assumptions that can be made when applying the method. The estimates of κ0 range between 0.0 17 and 0.031 s at the surface and between 0.004 and 0.024 s at rock. This variability due to the assumptions made is larger than the error of each estimate and larger than the average difference in values between sediment and rock. For this data set, part of it can be attributed to the type of distance used. Given this variability, κ0 values across literature may not always be comparable; this may bias the results of applications using κ0 as an input parameter, such as ground-motion prediction equations. We suggest ways to render the process more homogeneous. We also find that κ at rock level is not well approximated by surface records from which we deconvolved the geotechnical transfer function. Finally, we compute κ on the vertical component and find a dependence of the vertical-to-horizontal κ ratio on site conditions. [ABSTRACT FROM AUTHOR]

Published
2013
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24. Reconstructed human epidermis as an efficient tool in the evaluation of the effects of UV irradiation and of the photoprotective capacities of a sunblock.

Author

Mavon, A., Gélis, C., and Vicendo, P.

Subjects
*EPIDERMIS, *ULTRAVIOLET radiation, *SKIN, *IRRADIATION, *SUNSCREENS (Cosmetics)
Abstract

Solar or UVA (ultraviolet A) irradiation of the skin causes biological damage, including apoptosis, which is evident in the form of sunburn cells and the overexpression of p53. These two parameters, as well as the measurement of cellular viability, were used to evaluate the effects of UV irradiation on a reconstructed human epidermis (RHE) model, with and without the photoprotection of a broad spectrum sunblock. Reconstructed epidermis models were irradiated by solar spectrum (420 mJ cm–2) or UVA (20 J cm–2). In the absence of irradiation, and with irradiation doses of 420 mJ cm–2 and 20 J cm–2, viability was estimated at 95, 12 and 70% respectively. Sunburn cells per cm were evaluated at 0, 41 and 22, respectively under these same conditions. The apoptotic response was studied through the expression of p53, which increased at first and was then followed by a specific cleavage, 24 h after irradiation at 420 mJ cm–2. However, in the presence of a broad spectrum sunblock preparation (a combination of OMC, MBTBP, TiO2 and ZnO) and after irradiation at 420 mJ cm–2 and 20 J cm–2, viability increased to 40 and 85% respectively. The number of sunburn cells (SBC) per cm fell to 12 and nine respectively. The photoprotection provided by the sunblock limited the increase in the expression of p53 and resulted in the total disappearance of the cleavage. This study shows that human reconstructed epidermis is a valid skin model for use in the evaluation of the effects of solar and UVA irradiation, as well as in the testing of the efficacy of sunfilters. [ABSTRACT FROM AUTHOR]

Published
2004
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25. International Benchmark on Numerical Simulations for 1D, Nonlinear Site Response (PRENOLIN): Verification Phase Based on Canonical Cases

Author

Gaetano Falcone, Fabrice Hollender, Alborz Ghofrani, Mahdi Taiebat, Michael Musgrove, Pierre-Yves Bard, Evangelia Garini, George Gazetas, Daniela Boldini, Luca Verrucci, Kohei Watanabe, Luis Fabian Bonilla, Aneta Richterova, Alex Nieto-Ferro, Peter Moczo, Annamaria di Lernia, Long Chen, Jian Shi, Boris Jeremić, Federico Pisanò, Stavroula Kontoe, Céline Gélis, Steve Kramer, James R. Gingery, Angelo Amorosi, Evelyne Foerster, Domniki Asimaki, Joseph Harmon, Julie Régnier, Sebastiano Foti, Jozef Kristek, Alessandro Pagliaroli, Giuseppe Tropeano, Anna Chiaradonna, Youssef M. A. Hashash, Silvana Montoya-Noguera, Maria Paola Santisi d'Avila, Francesco Silvestri, Susumu Iai, Florent Demartin, Nathalie Glinsky, Marco Ebrille, Fernando Lopez-Caballero, Suwal Sajana, Etienne Bertrand, Deborah Sicilia, Amalia Giannakou, Graeme McAllister, E. Diego Mercerat, Pedro Arduino, Hiroshi Kawase, Giuseppe Lanzo, Ahmed Elgamal, Marianne Marot, Régnier, Julie, Bonilla, Luis‐fabian, Bard, Pierre‐yve, Bertrand, Etienne, Hollender, Fabrice, Kawase, Hiroshi, Sicilia, Deborah, Arduino, Pedro, Amorosi, Angelo, Asimaki, Domniki, Boldini, Daniela, Chen, Long, Chiaradonna, Anna, Demartin, Florent, Ebrille, Marco, Elgamal, Ahmed, Falcone, Gaetano, Foerster, Evelyne, Foti, Sebastiano, Garini, Evangelia, Gazetas, George, Gélis, Céline, Ghofrani, Alborz, Giannakou, Amalia, Gingery, James R., Glinsky, Nathalie, Harmon, Joseph, Hashash, Youssef, Iai, Susumu, Jeremić, Bori, Kramer, Steve, Kontoe, Stavroula, Kristek, Jozef, Lanzo, Giuseppe, Lernia, Annamaria di, Lopez‐caballero, Fernando, Marot, Marianne, Mcallister, Graeme, Diego Mercerat, E., Moczo, Peter, Montoya‐noguera, Silvana, Musgrove, Michael, Nieto‐ferro, Alex, Pagliaroli, Alessandro, Pisanò, Federico, Richterova, Aneta, Sajana, Suwal, Santisi d'Avila, Maria Paola, Shi, Jian, Silvestri, Francesco, Taiebat, Mahdi, Tropeano, Giuseppe, Verrucci, Luca, Watanabe, Kohei, Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement - Equipe-projet MOUVGS (Cerema Equipe-projet MOUVGS), Centre d'Etudes et d'Expertise sur les Risques, l'Environnement, la Mobilité et l'Aménagement (Cerema), Séismes et Vibrations (IFSTTAR/GERS/SV), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Communauté Université Paris-Est, 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), 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), CEA Cadarache, Commissariat à l'énergie atomique et aux énergies alternatives (CEA), Disaster Prevention Research Institute, Kyoto University [Kyoto], Département de sismologie (DS (UMR_7580)), IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Laboratoire de mécanique des sols, structures et matériaux (MSSMat), Centre National de la Recherche Scientifique (CNRS)-CentraleSupélec, Régnier, J., Bonilla, L.F., Bard, P.Y., Bertrand, E., Hollender, F., Kawase, H., Sicilia, D., Arduino, P., Amorosi, A., Asimaki, D., Boldini, D., Chen, L., Chiaradonna, A., Demartin, F., Ebrille, M., Elgamal, A., Falcone, G., Foerster, E., Foti, S., Garini, E., Gazetas, G., Gélis, C., Ghofrani, A., Giannakou, A., Gingery, J.R., Glinsky, N., Harmon, J., Hashash, Y., Iai, S., Jeremić, B., Kramer, S., Kontoe, S., Kristek, J., Lanzo, G., di Lernia, A., Lopez-Caballero, F., Marot, M., Mcallister, G., Mercerat, E.D., Moczo, P., Montoya-Noguera, S., Musgrove, M., Nieto-Ferro, A., Pagliaroli, A., Pisanò, F., Richterova, A., Sajana, S., Santisi d'Avila, M.P., Shi, J., Silvestri, F., Taiebat, M., Tropeano, G., Verrucci, L., Watanabe, K., 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])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Disaster Prevention Research Institute (DPRI), CentraleSupélec-Centre National de la Recherche Scientifique (CNRS), Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Université Paris Diderot - Paris 7 (UPD7)-IPG PARIS-Centre National de la Recherche Scientifique (CNRS), Kyoto University, Université Paris Diderot - Paris 7 (UPD7)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etudes de Mécanique Sismique (EMSI), Service d'Etudes Mécaniques et Thermiques (SEMT), Département de Modélisation des Systèmes et Structures (DM2S), CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-CEA-Direction des Energies (ex-Direction de l'Energie Nucléaire) (CEA-DES (ex-DEN)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Département de Modélisation des Systèmes et Structures (DM2S), and Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay

Subjects
Geochemistry & Geophysics, Peak ground acceleration, Earthquake, Wave propagation, Computation, 0211 other engineering and technologies, 0404 Geophysics, 02 engineering and technology, Seismic, 010502 geochemistry & geophysics, Civil Engineering, 01 natural sciences, 0905 Civil Engineering, Viscoelasticity, Ground response analysis, Geochemistry and Petrology, Applied mathematics, Boundary value problem, seismic response analysis, numerical modelling, ComputingMilieux_MISCELLANEOUS, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Mathematics, Geophysics, Computer simulation, business.industry, [SPI.GCIV.GEOTECH]Engineering Sciences [physics]/Civil Engineering/Géotechnique, Structural engineering, Dissipation, Nonlinear system, geophysics, geochemistry and petrology, [SPI.GCIV.DV]Engineering Sciences [physics]/Civil Engineering/Dynamique, vibrations, business
Abstract

© 2016 Seismological Society of America. All rights reserved. PREdiction of NOn-LINear soil behavior (PRENOLIN) is an international benchmark aiming to test multiple numerical simulation codes that are capable of predicting nonlinear seismic site response with various constitutive models. One of the objectives of this project is the assessment of the uncertainties associated with nonlinear simulation of 1D site effects. A first verification phase (i.e., comparison between numerical codes on simple idealistic cases) will be followed by a validation phase, comparing the predictions of such numerical estimations with actual strongmotion recordings obtained at well-known sites. The benchmark presently involves 21 teams and 23 different computational codes. We present here the main results of the verification phase dealing with simple cases. Three different idealized soil profiles were tested over a wide range of shear strains with different input motions and different boundary conditions at the sediment/bedrock interface. A first iteration focusing on the elastic and viscoelastic cases was proved to be useful to ensure a common understanding and to identify numerical issues before pursuing the nonlinear modeling. Besides minor mistakes in the implementation of input parameters and output units, the initial discrepancies between the numerical results can be attributed to (1) different understanding of the expression “input motion” in different communities, and (2) different implementations of material damping and possible numerical energy dissipation. The second round of computations thus allowed a convergence of all teams to the Haskell–Thomson analytical solution in elastic and viscoelastic cases. For nonlinear computations, we investigate the epistemic uncertainties related only to wave propagation modeling using different nonlinear constitutive models. Such epistemic uncertainties are shown to increase with the strain level and to reach values around 0.2 (log10scale) for a peak ground acceleration of 5 m=s2at the base of the soil column, which may be reduced by almost 50% when the various constitutive models used the same shear strength and damping implementation.

Published
2016
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26. The contribution of calpains in the down-regulation of Mdm2 and p53 proteolysis in reconstructed human epidermis in response to solar irradiation.

Author

Gélis C, Mavon A, and Vicendo P

Subjects
Epidermis enzymology, Epidermis radiation effects, Gene Expression Regulation drug effects, Humans, Proto-Oncogene Proteins c-mdm2, Calpain metabolism, Epidermis physiology, Gene Expression Regulation radiation effects, Nuclear Proteins genetics, Proto-Oncogene Proteins genetics, Sunlight, Ultraviolet Rays
Abstract

The p53 protein accumulates in human skin cells in vitro and in vivo when UV-irradiated. The transient stability of p53 requires a decrease in the activity of the ubiquitin ligase murine double minute 2 (Mdm2). Solar light irradiation (52.5, 105 and 405 mJ/cm2) of reconstructed human epidermis caused cutaneous damage. Specifically, UV-B induced the formation of sunburn cells and at first, an increase in the accumulation of p53 protein. Unexpectedly, 24 h after irradiation, a specific proteolytic cleavage of p53 resulted in the formation of a 40 kDa fragment. Both the accumulation of p53 and the proteolytic cleavage increased, commensurate with the UV dose. In contrast to p53, the level of expression of Mdm2 decreased drastically with the UV dose. It is important to note that calpastatin (20 microM), a specific inhibitor of calpains, decreased the formation of sunburn cells, inhibited the cleavage of p53 and induced an accumulation of Mdm2. The apoptotic process is strongly repressed. This demonstrates for the first time that calpains can participate in the down-regulation of Mdm2 in the epidermis very rapidly after UV irradiation, and that they contribute to a specific cleavage of p53 protein. All of these processes may be involved in the apoptotic response of the skin to UV stimulation.

Published
2005
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27. Assessment of the skin photoprotective capacities of an organo-mineral broad-spectrum sunblock on two ex vivo skin models.

Author

Gélis C, Girard S, Mavon A, Delverdier M, Paillous N, and Vicendo P

Subjects
Animals, Blotting, Western, Cinnamates pharmacology, Female, Humans, In Vitro Techniques, Phenols pharmacology, Rats, Titanium pharmacology, Triazines pharmacology, Ultraviolet Rays adverse effects, Zinc Oxide pharmacology, Skin drug effects, Skin radiation effects, Sunscreening Agents pharmacology
Abstract

UV irradiation can cause cutaneous damage that may be specific according to the wavelength of UV rays. For example, damage from UVB irradiation manifests itself in the form of sunburn cells and enhancement of the expression of p53, while damage from UVA exposure results in an increase in the expression of vimentin. These reactions to UV irradiation were used in this work to evaluate the photoprotective capacities of two sunblock preparations that were applied to the surface of the skin. One sunblock preparation is a UVB absorber containing zinc oxide (ZnO) and titanium oxide (TiO2) exclusively. The other sunblock preparation is a new organo-mineral sunblock containing Tinosorb M, OCM, ZnO and TiO2. Evaluation of the photoprotective capacities of both preparations on hairless rat skin and on in vitro reconstructed human epidermis revealed that they were effective in preventing UVB-induced damage. In contrast, only the organo-mineral sunblock was effective in the prevention of UVA-specific damage such as dermal alterations characterized by the expression of vimentin. Furthermore, our data support the fact that hairless rat skin and in vitro reconstructed human epidermis are a reliable basis for the evaluation of the photoprotective capacities of various sunscreens against UVB and UVA damage.

Published
2003
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28. Modifications of in vitro skin penetration under solar irradiation: evaluation on flow-through diffusion cells.

Author

Gélis C, Mavon A, Delverdier M, Paillous N, and Vicendo P

Subjects
Animals, Cell Culture Techniques methods, Cell Survival radiation effects, Diffusion, Male, Rats, Rats, Inbred Strains, Skin cytology, Skin radiation effects, Sunlight, Ultraviolet Rays
Abstract

The effect of solar irradiation on ex vivo dermatomed hairless rat skin samples maintained in culture on flow-through diffusion cells for at least 24 h was evaluated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay and by histological observations. Transepidermal water loss (TEWL) measurements and kinetic analysis of the permeation of both tritiated water and 14C caffeine through the skin were performed after full-spectrum solar exposure involving the use of a xenon arc solar simulator. After a UV exposure of less than 420 mJ/cm2, skin integrity and permeation of both water and caffeine did not change significantly. In contrast, after a 420 mJ/cm2 UV exposure, the epidermis appeared more contracted, associated with an increase of 55% of TEWL and 220% of the skin permeation of tritiated water after 6 h. The data suggested a dramatic alteration of the skin barrier integrity. Moreover, the flux of 14C caffeine increased rapidly by 338% of the absorption of water 12 h after irradiation. These results reveal the presence of a threshold UV exposure that would not modify skin penetration.

Published
2002
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29. [Reflections about the present and future of hearing aids].

Author

Gélis C

Subjects
Amplifiers, Electronic trends, Forecasting, Hearing Loss rehabilitation, Humans, Medical Laboratory Science, Miniaturization, Cochlear Implants, Hearing Aids trends
Abstract

For a long time hearing aids were the only solution for the deaf to perceive speech and sounds. Today, among the new deaf-aids, acoustic amplification still offers the easiest and most versatile means of combatting the majority of such handicaps. However, due to the fundamental inadequacy of amplification in compensating frequency selectivity, audiologist are obliged to pay particular attention to the improvement of the signal/noise ratio and to observe a rigourous procedure in choosing and fittings hearing aids to the user. In the future, signal processing in digital devices should contribute to enhancing the efficacy of the prosthesis.

Published
1991

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