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Electronic Supplements 1. Table S1: Summary of the database used in regression analyses 2. Excel file including the full list of regression coefficients of the proposed GMPEs of R JB , R epi and R hyp and a macro for the computation of spectral ordinates for different earthquake scenarios 3. Matlab and Excel codes of the proposed GMPEs and a sample input file 2 AbstractThis article presents the latest generation of ground-motion models for the prediction of elastic response (pseudo-) spectral accelerations, as well as peak ground acceleration and velocity, derived using pan-European databases. The models present a number of novelties with respect to previous generations of models (Ambraseys et al., 1996(Ambraseys et al., , 2005Bommer et al., 2003;Akkar and Bommer, 2010), namely: inclusion of a non-linear site-amplification function that is a function of V S30 and reference peak ground acceleration on rock; extension of the magnitude range of applicability of the model down to M w 4; extension of the distance range of applicability out to 200km; extension to shorter and longer periods (down to 0.01s and up to 4s); and consistent models for both point-source (epicentral, R epi , and hypocentral distance, R hyp ) and finite-fault (distance to the surface projection of the rupture, R JB ) distance metrics. In addition, data from more than 1.5 times as many earthquakes, compared to previous pan-European models, have been used, leading to regressions based on approximately twice as many records in total. The metadata of these records have been carefully compiled and reappraised in recent European projects. These improvements lead to more robust ground-motion prediction equations than have previously been published for shallow (focal depths less than 30km) crustal earthquakes in Europe and the Middle East. We conclude with suggestions for the application of the equations to seismic hazard assessments in Europe and the Middle East within a logic-tree framework to capture epistemic uncertainty.

Empirical equations are presented for the prediction of displacement response ordinates for damping ratios of 2, 5, 10, 20 and 30% of critical and for response periods up to 4 s, using 532 accelerograms from the strong-motion databank from Europe and the Middle East. The records were all re-processed and only employed for regressions at periods within the usable range, defined as a fraction of the filter cut-off and depending on the instrument type (digital or analogue), earthquake magnitude and site class. The equations can be applied to predict the geometric mean displacement and pseudo-acceleration spectra for earthquakes with moment magnitudes (M) between 5 and 7.6, and for distances up to 100 km. The equations also include style-of-faulting and site class as explanatory variables. The predictions obtained from these new equations suggest that earlier European equations for spectral displacements underestimate the ordinates at longer periods as a result of severe filtering and the use of the spectral ordinates at periods too close to the filter cut-off. The results also confirm that the period defining the start of the constant displacement plateau in the Eurocode 8 (EC8) spectrum is excessively short at 2 s. The results not only show that the scaling factor defined in EC8 for estimating the spectral ordinates at damping ratios different from 5% of critical are a good general approximation, but also that this scaling varies with magnitude and distance (reflecting the influence of duration) and also displays a mild dependence on response period. devices to enhance seismic performance gives rise to the need for elastic design response spectra that extend to longer periods than have traditionally been considered, and also have higher damping ratios than the nominal 5% of critical assumed in most design codes.The same long-period and highly-damped response spectral ordinates are also required for direct displacement-based design approaches that make use of equivalent linearization (e.g.[1]). Some researchers have shown that the use of equivalent linearization in displacement-based design may result in biased deformation demand estimations particularly for weak structures (e.g.[2]). However, both FEMA-440 [3] and Eurocode 8 (EC8) [4] acknowledge the viability of both equivalent linear and displacement modification approaches, given that each has its own advantages and limitations, and a consensus view has yet to be reached amongst earthquake engineers. Although EC8 does envisage, through Informative Annexes, the possible use of both approaches to displacement-based design, the implementation of the equivalent linearization approach is currently far less developed in the code [5].One of the primary motivations for the present study is precisely to provide predictive equations for displacement response ordinates that may be used to re-evaluate the spectra currently defined in EC8. Concern has been expressed recently that the EC8 spectral ordinates may be excessively low at longer periods [5,6], particularly if compa...

This paper presents the overall procedure followed in order to assemble the most recent pan-European strong-motion databank: Reference Database for Seismic Ground-Motion in Europe (RESORCE). RESORCE is one of the products of the SeIsmic Ground Motion Assessment (SIGMA; projet-sigma.com) project. RESORCE is intended to be a single integrated accelerometric databank for Europe and surrounding areas for use in the development and testing of ground-motion models and for other engineering seismology and earthquake engineering applications. RESORCE aims to contribute to the improvement of earthquake risk studies in Europe and surrounding areas. RESORCE principally updates and extends the previous pan-European strong-motion databank (Ambraseys et al. in Bollettino di Geofisica Teorica ed Applicata 45:113-129, 2004a) with recently compiled Greek, Italian, Swiss and Turkish accelerometric archives. The updates also include earthquake-specific studies published in recent years. The current content of RESORCE includes 5,882 multi-component and uniformly processed accelerograms from 1,814 events and 1,540 strong-motion stations. The moment magnitude range covered by RESORCE is {Mathematical expression}. The source-to-site distance interval extends to 587 km and distance information is given by the common point- and extended-source distance measures. The paper presents the current features of RESORCE through simple statistics that also quantify the differences in metadata and strong-motion processing with respect to the previous version of the pan-European strong-motion databank

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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

Peak ground velocity (PGV) has many applications in earthquake engineering, but there are relatively few prediction equations for this parameter in comparison with the large numbers of equations for estimating peak ground acceleration and response spectral ordinates. This lack of empirical equations for PGV has led to widespread use of the practice of scaling peak velocity from the 5%-damped response spectral ordinate at 1 sec, which is a poor substitute for direct prediction of the parameter. Responding to the need to provide equations for the prediction of PGV, this article derives new equations using the strong-motion database for the seismically active areas of Europe and the Middle East, following a new processing of all of the records. A total of 532 strong-motion accelerograms recorded at distances of up to 100 km from 131 earthquakes with moment magnitudes ranging from M 5 to 7.6 are used to derive equations for both the larger and the geometric mean of the horizontal components. The predictions are found to be broadly consistent with those from previous European equations, and also with preliminary results from the Next Generation of Attenuation (NGA) project, suggesting that systematic differences in ground motions from active crustal regions, if any, are sufficiently small not to prevent the combined use of strong-motion data from southern Europe, western North America, and other tectonically active areas of shallow crustal seismicity.

SUMMARYThe e ect of the long-period ÿlter cut-o , Tc, on elastic spectral displacements is investigated using a strong ground-motion database from Europe and the Middle East. The relation between the ÿlter and oscillator responses is considered to observe the in uence of Tc for both analogue and digital records, and the variations with site classiÿcation, magnitude, ÿlter order and viscous damping. Robust statistics are derived using the re-processed European data to generalize the e ects of the longperiod ÿlter cut-o on maximum oscillator deformation demands as a function of these seismological and structural features. Statistics with a 95% conÿdence interval are derived to suggest usable period ranges for spectral displacement computations as a function of Tc. The results indicate that the maximum period at which spectral displacements can be conÿdently calculated depend strongly on the site class, magnitude and ÿlter order. The period range where reliable long-period information can be extracted from digital accelerograms is twice that of analogue records.