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603284-001 <br />2010 CBC Based Seismic Design Parameters (Mapped Values) <br />Categorization/Coefficient Design Value <br />Site Latitude 33.76184N <br />Site Longitude -117.90095W <br />Site Class E <br />Mapped spectral response acceleration parameter at short 1.39period, SS <br />Mapped spectral response acceleration parameter at a 0.50period of 1 sec, Sl <br />Short Period (0.2 sec) Site Coefficient, Fa 0.9 <br />Long Period (1.0 sec) Site Coefficient, F 2.4 <br />Adjusted spectral response acceleration parameter at short 1.25period, SMS <br />Adjusted spectral response acceleration parameter at a 1.19period of 1 sec, SM1 <br />Design spectral response acceleration parameter at short 0.83period, SDS <br />Design spectral response acceleration parameter at a 0.79period of 1 sec, Soi <br />Attenuation Relationships <br />Attenuation relationships describe the relation of ground motion levels with earthquake <br />magnitude and distance (distance between the site and seismic source), site geology, <br />and subsurface characterization. These relationships can be used to describe the <br />variation of peak ground and response spectral acceleration with earthquake magnitude <br />and distance, and to also incorporate the local geological conditions and near-source <br />effects. Next Generation Attenuation (NGA) relationships by Boore and Atkinson <br />(2008), Campbell and Bozorgnia (2008) and Chiou and Youngs (2007) were used in our <br />analyses. Sc (Soil) soil profile was considered for this site based on the shear wave <br />velocity profile in the upper 30 meters (VS30). <br />These attenuation relationships are based on the geometric mean of the horizontal <br />components. The versions of the attenuation relationships adjust the geometric mean <br />to the maximum direction of ground motion represented by a 5 percent damped <br />acceleration response spectrum using FEMA P-750 2009 NEHRP Recommended <br />Seismic Provisions Table C21.2-1. The selected attenuation relationships also provide <br />an implied measure of the near-field effects on ground motions. All three relationships <br />include additional aleatory uncertainty in the hazard calculation and truncation of <br />residuals at three sigma as described in the USGS open File Report (OFR) 2008-1128 <br />(Petersen et al, 2008). <br />D-5