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Imperial College London, United Kingdom
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- PublicationRestrictedAn evolutionary stochastic ground-motion model defined by a seismological scenario and local site conditions(2011)
; ; ; ; ; ; ;This paper is concerned with modeling earthquake-induced ground accelerations and the simulation of the dynamic response of linear structures through the principles of stochastic dynamics. A fully evolutionary approach, with nonstationarity both in amplitude and in frequency content, is proposed in order to define the seismic action, based on seismological information in the form of a small number of input parameters commonly available in deterministic or probabilistic seismic design situations. The signal is obtained by filtering a Gaussian white-noise. The finite duration and time-varying amplitude properties are obtained by using a suitable envelope function. By utilizing a subset of the records from the PEER-NGA strong-motion database, and time-series analysis tools extended to nonstationary processes, the key transfer-function properties, in terms of circular frequency, damping ratio and spectral intensity factor, are identified. A regression analysis is conducted for practical and flexible application of this model, in order to empirically relate the identified time-varying parameters of the filter to the characteristics defining earthquake scenarios such as magnitude, rupture distance and soil type. A validation study and a parametric investigation using elastic response spectra is also included. Results show that the final seismic model can reproduce, with satisfactory accuracy, the characteristics of acceleration records in a region, over a broad range of response periods.159 1 - PublicationOpen AccessComparisons 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(2014-02)
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ;Douglas, J.; BRGM, Orléans, France ;Akkar, S.; Middle East Technical University, Ankara, Turkey ;Ameri, G.; FUGRO-Geoter, Auriol, France. ;Bard, P.; ISTerre, Grenoble, France ;Bindi, D.; GFZ, Potsdam, Germany ;Bommer, J.; Imperial College London, United Kingdom ;Bora, S. S.; Inst. Erd- und Umweltwissesnschaften, Universitaet Potsdam, Germany ;Cotton, F.; ISTerre, Grenoble, France ;Derras, B.; ISTerre, Grenoble, France ;Hermkes, M.; Inst. Erd- und Umweltwissesnschaften, Universitaet Potsdam, Germany ;Kuehn, N. M.; Inst. Erd- und Umweltwissesnschaften, Universitaet Potsdam, Germany ;Luzi, L.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Massa, M.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Pacor, F.; Istituto Nazionale di Geofisica e Vulcanologia, Sezione Milano-Pavia, Milano, Italia ;Riggelsen, C.; Inst. Erd- und Umweltwissesnschaften, Universitaet Potsdam, Germany ;Sandikkaya, M. A.; Middle East Technical University, Ankara, Turkey ;Scherbaum, F.; Inst. Erd- und Umweltwissesnschaften, Universitaet Potsdam, Germany ;Stafford, P.; Imperial College London, United Kingdom ;Traversa, P.; EDF, Aix en Provence, France; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; This article presents comparisons among the five ground-motion models described in other articles within this special issue, in terms of data selection criteria, characteristics of the models and predicted peak ground and response spectral accelerations. Comparisons are also made with predictions from the Next Generation Attenuation (NGA) models to which the models presented here have similarities (e.g. a common master database has been used) but also differences (e.g. some models in this issue are nonparametric). As a result of the differing data selection criteria and derivation techniques the predicted median ground motions show considerable differences (up to a factor of two for certain scenarios), particularly for magnitudes and distances close to or beyond the range of the available observations. The predicted influence of style-of-faulting shows much variation among models whereas site amplification factors are more similar, with peak amplification at around 1s. These differences are greater than those among predictions from the NGA models. The models for aleatory variability (sigma), however, are similar and suggest that ground-motion variability from this region is slightly higher than that predicted by the NGA models, based primarily on data from California and Taiwan.214 263