Key structural parameters affecting earthquake ground motion in 2D and 3D sedimentary structures

Autor: Svetlana Stripajova, Miriam Kristekova, Pierre-Yves Bard, Peter Moczo, Jozef Kristek, Deborah Sicilia, Fabrice Hollender, Zuzana Chovanová
Přispěvatelé: Faculty of Mathematics, Physics and Informatics [Bratislava] (FMPH/UNIBA), Comenius University in Bratislava, Institut des Sciences de la Terre (ISTerre), 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]), Geophysical Institute, Slovak Academy of Science [Bratislava] (SAS), EDF Ceidre TEGG
Rok vydání: 2018
Předmět:
Zdroj: Bulletin of Earthquake Engineering
Bulletin of Earthquake Engineering, Springer Verlag, 2018, 16, pp.2421-2450. ⟨10.1007/s10518-018-0345-5⟩
Bulletin of Earthquake Engineering, 2018, 16, pp.2421-2450. ⟨10.1007/s10518-018-0345-5⟩
ISSN: 1573-1456
1570-761X
DOI: 10.1007/s10518-018-0345-5
Popis: Alluvial valleys generate strong effects on earthquake ground motion (EGM). These effects are rarely accounted for even in site-specific studies because of (a) the cost of the required geophysical surveys to constrain the site model, (b) lack of data for empirical prediction, and (c) poor knowledge of the key controlling parameters. We performed 3D, 2D and 1D simulations for six typical sedimentary valleys of various width and depth, and for a variety of modifications of these 6 “nominal models” to investigate sensitivity of EGM characteristics to impedance contrast, attenuation, velocity gradient and geometry. We calculated amplification factors, and 2D/1D and 3D/2D aggravation factors for 10 EGM characteristics, using a representative set of recorded accelerograms to account for input motion variability. The largest values of the amplification and aggravation factors are found for the Arias intensity and cumulative absolute velocity, the lowest for the root-mean-square acceleration. The aggravation factors are largest for the vertical component. For each model, at least one EGM characteristic exhibits a significant 2D/1D aggravation factor, while all EGM characteristics exhibit significant 2D/1D aggravation factor on the vertical component. For all investigated sites, there is always an area in the valley for which 1D estimates are not sufficient. 2D estimates are insufficient at several sites. The key structural parameters are the shape ratio and overall geometry of the sediment-bedrock interface, impedance contrast at the sediment-bedrock interface, and attenuation in sediments. The amplification factors may largely exceed the values that are usually considered in GMPEs between soft soils and rock sites.
Databáze: OpenAIRE