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Project No. D-3885-06 Christ Our Savior Catholic Parish We have used this method and the results of the liquefaction study including depth vs. factor of safety, soil behavior type, and cyclic stress ratio, based on the site profile are presented in Appendix E. In accordance with the latest USGS Design Maps in the 2010 ASCE-7 Standard for Risk Category I/llllII, adjusted for other site class D,5% Damped Design Spectral Acceleration at short period, Sp5 is l.02lg and Sp1 for long period is 0.5689. Liquefaction is generally analyzed for Sp5/2.5 = 0.41g or 0.586 g from Figure 22-7 (USGS, Design Maps) or 2% probability of exceedance in 50 years is 0.78529 in accordance with U.S.G.S. National Seismic Hazard Mapping Project PSH Deaggregation Interactive program, and 213 rd of 0.78529 = 0.5239. Thus, as per USGS Design Maps, Figrre 22-7 of 0.5869 is more conservative and has been used in liquefaction analysis. Liquefaction analyses have been performed for earthquake magnitude of M6.6 and ground acceleration of 0.59g. Historical high groundwater depth was considered as 5 feet below the existing ground surface. Results of the liquefaction study including depth vs. factor of safety and estimated settlements for liquefiable layers based on generalized soil profile for CPT's and borings are all presented in Appendix E. Liq uefaction-Ind uced Settlement of Saturated Soils t7 l I I I I I I I I t I I T I I I u As a result of liquefaction, the proposed structure may be subject to several hazards including liquefaction-induced settlement. In order to estimate the amount of post- earthquake settlement, the method proposed by Tokimatsu and Seed (1987) was used in which the seismically induced cyclic stress ratios and corrected N-values are related to the volumetric strain of the soil. The amount of soil settlement during a strong seismic event depends on the thickness of the liquefiable layers, the density and/or consistency of the soils and groundwater level. Computer analysis of estimated settlement, based on data from SPT and Cone Penetration tests are presented in Appendix E. E r