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5/1512015 Design Maps Detailed Report <br />Design Maps Detailed Report <br />ASCE 7-10 Standard (37.796420N, 121.20614°W) <br />�e Class D - "Stiff Soil", Risk Category I/II/III <br />Section 11.4.1 — Mapped Acceleration Parameters <br />Note: Ground motion values provided below are for the direction of maximum horizontal <br />spectral response acceleration. They have been converted from corresponding geometric <br />mean ground motions computed by the USGS by applying factors of 1.1 (to obtain Sy) and <br />1.3 (to obtain S,). Maps in the 2010 ASCE-7 Standard are provided for Site Class B. <br />Adjustments for other Site Classes are made, as needed, in Section 11.4.3. <br />From Figure 22-1 "1 Ss = 0.970 g <br />From Figure 22-2 [21 S1 = 0.348 g <br />Section 11.4.2 — Site Class <br />The authority having jurisdiction (not the USGS), site-specific geotechnical data, and/or the <br />default has classified the site as Site Class D, based on the site soil properties in accordance <br />with Chapter 20. <br />Table 20.3-1 Site Classification <br />Site Classv5 <br />Nor R. <br />S. <br />A. Hard Rock <br />>5,000 ft/s <br />N/A <br />N/A <br />B. Rock <br />2,500 to 5,000 ft/s <br />N/A <br />N/A <br />C. Very dense soil and soft rock <br />1,200 to 2,500 ft/s <br />>50 <br />>2,000 psf <br />D. Stiff Soil <br />600 to 1,200 ft/s <br />15 to 50 <br />1,000 to 2,000 psf <br />E. Soft clay soil <br /><600 ft/s <br /><15 <br /><1,000 psf <br />Any profile with more than 10 ft of soil having the <br />characteristics: <br />• Plasticity index PI > 20, <br />• Moisture content w >_ 40%, and <br />• Undrained shear strength su < 500 psf <br />F. Soils requiring site response See Section 20.3.1 <br />analysis in accordance with Section <br />21.1 <br />For SI: lft/s = 0.3048 m/s lib/ftz = 0.0479 kN/mz <br />