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NGA-West2 Ground Motion Model for the Average Horizontal Components of PGA, PGV, and 5% Damped Linear Acceleration Response Spectra Kenneth W. Campbella) M.EERI, and Yousef Bozorgniab) M.EERI We used an expanded PEER NGA-West2 database to develop a new ground motion prediction equation (GMPE) for the average horizontal components of PGA, PGV, and 5% damped linear pseudo-absolute acceleration response spectra at 21 periods ranging from 0.01 s to 10 s. In addition to those terms included in our now superseded 2008 GMPE, we include a more-detailed hanging wall model, scaling with hypocentral depth and fault dip, regionally independent geometric attenuation, regionally dependent anelastic attenuation and site conditions, and magnitude-dependent aleatory variability. The NGA-West2 database provides better constraints on magnitude scaling and attenuation of small-magnitude earthquakes, where our 2008 GMPE was known to be biased. We consider our new GMPE to be valid for estimating horizontal ground motion from shallow crustal continental earthquakes in an active tectonic domain for rupture distances ranging from 0 km to 300 km and magnitudes ranging from 3.3 to 7.5–8.5, depending on source mechanism. [DOI: 10.1193/062913EQS175M] به نقل از گروه تلگرام دستنامه زلزله دانلود از پیوست campbell2014.pdf

Summary of the ASK14 Ground Motion Relation for Active Crustal Regions Norman A. Abrahamson,a) M.EERI, Walter J. Silva, M.EERI, and Ronnie Kamai,c) M.EERI Empirical ground motion models for the average horizontal component from shallow crustal earthquakes in active tectonic regions are derived using the PEER NGA-West2 database. The model is applicable to magnitudes 3.0–8.5, distances 0–300 km, and spectral periods of 0–10 s. The model input parameters are the same as those used by Abrahamson and Silva (2008), with the following exceptions: the loading level for nonlinear effects is based on the spectral acceleration at the period of interest rather than the PGA; and the distance scaling for hanging wall (HW) effects off the ends of the rupture includes a dependence on the sourceto- site azimuth. Regional differences in large-distance attenuation and VS30 scaling between California, Japan, China, and Taiwan are included. The scaling for the HW effect is improved using constraints from numerical simulations. The standard deviation is magnitude-dependent, with smaller magnitudes leading to larger standard deviations at short periods, but smaller standard deviations at long periods. Directivity effects are not included through explicit parameters, but are captured through the variability of the empirical data. [DOI: 10.1193/ 070913EQS198M] به نقل از گروه تلگرام دستنامه زلزله دانلود از پیوست abrahamson2014.pdf

Effects of the Soil-Foundation-Structure Interaction on the Component Demand Modifier Factor of Concrete Gravity Beams based on ASCE 41-06 Standard A Azarbakht; E Rajabi The aim of the present paper is to evaluate the influence of the Soil- Foundation- Structure Interaction (SFSI) effects on the component demand modifier factor of concrete gravity beams based on ASCE 41-06 standard. To this end, the beam on the nonlinear Winkler foundation approach is employed which is a simple and efficient method. At first, four sets of 3-, 6-, 10- and 15-storey concrete moment-resisting frames founded on soft, medium and hard soils are designed and analysed for the case of fixed-base and flexible-base assumptions. A comparison is then made between the results of the nonlinear response history analysis of each frame in the flexible-base and fixed-base conditions with the response based on the equivalent linear static approach. The findings show that the equivalent linear static approach loads for gravity beams, which are controlled by deformation actions, can lead to non-conservative predictions of seismic demand. Finally, a modified load combination is proposed to be used in the equivalent linear static approach to avoid this imperfection. منبع دانلود JSEG181348691400.pdf