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Geotechnical Engineering Investigation Page 20 of 24 New Residential Subdivision 2706 Pock Lane Stockton, CA 95205 March 30, 2021 CTE Job # 25-1097G Mapped NICE Geometric Peak Ground Acceleration Adjusted for Site 0.385g ASCE 7,Chapter 11 Class Effects,PGA. Seismic Design Category D ASCE 7,Chapter 11 IL 'In general accordance with the 2019 CBC 1613.2.2. CBC Site Class is based on the average characteristics of the upper 100 feet of the subsurface profile. 2 The 2019 CBC requires a site soil profile determination extending to a depth of 100 feet for seismic site classification.Borings for this study extended to a maximum depth of 30±feet,and this seismic site class definition considers soils below the explored depth to be consistent with the stiff soils encountered at shallower depths. 3 F„is calculated in accordance with ASCE 7-16 Table 11.4-2 assuming that the exception for Site Class D with S1 greater than or equal to 0.2 will be applied. a SMI is calculated in accordance with ASCE 7-16 Section 11.4.4 s SDI is calculated in accordance with ASEC 7-16 Section 11.4.5 The site could be subjected to significant shaking in the event of a major earthquake on any of the faults listed above or other active faults within northern California. Per ASCE 7-16 Section 11.4.8, a site-specific ground motion procedure would be required for the structure since the site falls under Class D, and the Si parameter is greater than or equal to 0.2. However, Exception (2) permits the use of the Code-Based ground motion values if the seismic response coefficient Cs is amplified by 1.5 times for the period range T>1.5Ts using equations 12.8-3 and 12.8-4 in ASCE 7-16. If the proposed developments have a period in the range exceeding 1.5Ts, then the base shear coefficient must be increased as required by ASCE 7-16. 5.9 Pavement Sections Pavements and flatwork can be founded on either lime treated subgrade soils, or tightly controlled moisture conditioned and compacted native materials. Curb and sidewalk areas should be constructed of Portland cement concrete. The upper 12 inches of lime treated subgrade and all aggregate base materials should be compacted to 95% of laboratory determined maximum dry density, as per ASTM D1557, at moisture contents of at least two percent above optimum. In non- treated areas, the upper 24 inches of non-treated subgrade should be compacted between 88-92% relative compaction at a moisture content of at least +3% above optimum per ASTM D1557. Pavements should be designed and constructed according to CALTRANS standards. Preliminary pavement sections presented below are based on a lab derived Resistance ("R")Value of 9 for native soils and 50 for lime treated soils, along with the assumed Traffic Indices presented