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Alliance Residence October 18,2016 <br />J.N.: 2530.00 <br />Page 6 <br />TABLE 4.1 <br />Total Static Settlements <br />Footing <br />Type <br />Continuous <br />Spread <br />Settlement <br />Column Bearing Footinf Embedment Without Settlement Fill(3) <br />Load Pressure Widthc 1 Depth(2)Fill With Fill Thickness <br />(kips)(psf) (ft) (ft) (in)(in) (ft) <br />2,000 1.0 1.5 0.20 <br />50 3,500 3.8 1.5 0.67 --- --- <br />100 3,500 5.3 1.5 0.92 --- <br />150 3,500 6.5 1.5 1.10 0.80 1.5 <br />200 3,500 7.6 1.5 1.23 0.93 1.5 <br />250 3,500 8.5 1.5 1.42 0.87 2.5 <br />300 3,500 9.3 1.5 1.56 1.00 2.5 <br />350 3,500 10.0 1.5 1.73 0.99 3.5 <br />400 3,500 10.7 1.5 2.60 0.97 4.5 <br />Notes: <br />1) For spread footings, this is the dimension of the (square) footing. <br />2) Embedment depth measured from the lowest adjacent grade or finish floor. <br />3) Fill thickness beneath the bottom of footing required to reduce the settlement to 1.0 inch or <br />less. <br />4.2.1 Liquefaction <br />Engineering research of soil liquefaction potential (Youd, et al., 2001) indicates that generally three <br />basic factors must exist concurrently in order for liquefaction to occur. These factors include: <br />• A source of ground shaking, such as an earthquake, capable of generating soil mass <br />distortions. <br />• A relatively loose silty and/or sandy soil. <br />• A relative shallow groundwater table (within approximately 50 feet below ground surfuce) or <br />completely saturated soil conditions that will allow positive pore pressure generation. <br />The liquefaction susceptibility of the onsite subsurface soils was evaluated by analyzing the potential <br />concurrent occurrence of the above-mentioned three basic factors. These analyses were completed <br />under the guidance of Special Publication 117A: Guidelines for Evaluating and Mitigating Seismic <br />Hazards in California (CDMG, 2008). CPT data and laboratory test results from the referenced <br />geotechnical investigation of 2016 by Group Delta Consultants were used for this purpose. The <br />tabular CPT data presented in Appendix A are reported average values across 1.Oft depth intervals, <br />whereas in liquefaction analyses electronic data from depth increment of 0.05m (approximately 2 <br />inches) is used. The seismic event was defined by peak ground acceleration of PGA=0.568g and <br />mean moment magnitude of 6.61 discussed in Section 4.1. Groundwater was assumed at depth 8 feet <br />below ground surface as indicated by the CDMG Seismic Hazard Zone Report 012, which is much <br />shallower than the encountered groundwater during subsurface investigation. <br />ALBUS-KEEFE & ASSOCIATES, INC.