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Table 1 <br />Seismic Design Parameters <br />Selected Parameters from 2019 CBC, Section 1613 - Earthquake Loads <br />Seismic Design <br />Values <br />Site Class per Chapter 20 of ASCE 7 <br />D* <br />Risk -Targeted Spectral Acceleration for Short Periods (Ss) <br />1.288g <br />Risk -Targeted Spectral Accelerations for 1-Second Periods (Si) <br />0.459g <br />Site Coefficient Fa per Table 1613.2.3(1) <br />1.0 <br />Site Coefficient Fv per Table 1613.2.3(2) <br />1.841 <br />Site Modified Spectral Acceleration for Short Periods (SMs) for Site Class D <br />[Note: SMs = FaSs] <br />1.288g <br />Site Modified Spectral Acceleration for 1-Second Periods (SMi) for Site Class D <br />[Note: SMi = FvSI] <br />0.845 <br />Design Spectral Acceleration for Short Periods (SDs) for Site Class D <br />a <br />[Note: SDS = (/3)SMS] <br />0.858g <br />Design Spectral Acceleration for 1-Second Periods (SDI) for Site Class D <br />[Note: SDI = C/3)SMI] <br />0.56333 <br />Seismic Design Category (per Section 1613.2.5) <br />D <br />CRS (Mapped Risk Coefficient at 0.2 sec, Per ASCE 7 Chapter 22 -Figure 22-18A) <br />0.935 <br />CRI (Mapped Risk Coefficient at 1 sec, Per ASCE 7 Chapter 22 — Figure 22-19A) <br />0.928 <br />*Structures on Site Class D sites with S1 greater than or equal to 0.2, provided the value of the <br />seismic response coefficient Cs is determined by Eq. (12.8-2) for values of T <_ 1.5Ts and taken as <br />equal to 1.5 times the value computed in accordance with either Eq. (12.8-3) for TL >_ T > 1.5Ts or <br />Eq. (12.8-4) for T > TL. <br />Section 1803.5.12 of the 2019 CBC (per Section 11.8.3 of ASCE 7) states that the maximum considered <br />earthquake ground motions, Peak Ground Acceleration (PGA) should be used for the geotechnical <br />evaluations. The PGAM for the site is equal to 0.593g (USGS Seismic Design Maps based on ASCE/SEI 7- <br />16 and ASCE/SEI 7-16 Table 1.5-2). <br />A deaggregation of the PGA based on a 2,475-year average return period indicates that an earthquake <br />magnitude of 7.71 at a distance of approximately 14.62 km (9.1 mi) from the site would contribute the most <br />to this ground motion (USGS, 2014). <br />Project i y ouncil 18 — 821 1 316, 2021 <br />