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rKLE NFELOER \\� J'Bright People.Righ}So7utFons. Table 5-3 General Ground Motion Parameters Based on 2019 CBC Parameter Value1 ASCE 7-16 Reference Ss 0.725 g Fig 22-1 Si 0.282 g Fig 22-2 Site Class D Table 20.3-1 Fa 1.22 Table 11.4-1 F„ N/A Table 11.4-2 PGA 0.303 g Fig 22-9 SMS 0.884 g Eq. 11.4-1 SMi N/A Eq. 11.4-2 SDS 0.589 g Eq. 11.4-3 Sol N/A Eq. 11.4-4 FPGA 1.297 Table 11.8-1 PGAM 0.393 g Eq. 11.8-1 CRs 0.948 Fig 22-18A CRS 0.95 Fig 22-19A TL 12 seconds 'N/A= Not Applicable It should be noted that Section 11.4.8 of ASCE 7-16 requires a site-specific ground motion hazard analysis be performed for Site Class D sites with S, values greater than or equal to 0.2g unless structural design exceptions are taken. The subject site meets these criteria. If exceptions are taken, then a Fv value of 1.700 can be used only to calculate the TS value. 5.4 LIQUEFACTION Soil liquefaction is a condition where saturated, granular soils undergo a substantial loss of strength and deformation due to pore pressure increase resulting from cyclic stress application induced by earthquakes. In the process, the soil acquires mobility sufficient to permit both horizontal and vertical movements if the soil mass is not confined. Soils most susceptible to liquefaction are saturated, loose, clean, uniformly graded, and fine-grained sand deposits. If liquefaction occurs,foundations resting on or within the liquefiable layer may undergo settlements. This will result in reduction of foundation stiffness and capacities. Based on the depth to groundwater and the fact that much of the underlying subgrade soil is very stiff to hard in consistency and dense in relative density, it is our professional opinion that the potential for significant liquefaction induced settlement at the project site is minor. 20210067.001 A/ST020R111447 Page 17 of 37 May 11, 2020 ©2020 Kleinfelder www.kleinfelder.com