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VsdmkE:; rove Grvder I'rojeCe: LF�o!.tur Foal[' 54ut!I L <br />Jw, VrngacI: NttEu %,: UG -0).88 <br />May M,'2007 <br />A Moblle B-53 drill rig utiiizing the mud rotary drilling method was used to drill the 41.5 <br />foot deep boring. As indicated, the drill rig has a calculated energy efficiency of 45 <br />percent. Our calculations are based on corrected blow counts and values of blow counts <br />reported in the bore logs are corrected (i.e. correction for a standard 60 percent <br />efficiency has been applied). <br />As was mentioned, two methods of analysis were used to assess the liquefaction <br />potential of the site. Both of these methods require the same input. Besides data <br />obtained during field and laboratory testing, a value of peak ground acceleration at the <br />site and a magnitude of the earthquake responsible for the peak ground acceleration <br />are required. A magnitude of 6.9 was selected as the design earthquake (Greenville <br />Fault located 54 kilometers away from the site) and a peak horizontal ground <br />acceleration of 0.236g was calculated and used in our liquefaction analysis. The shear <br />wave velocity was estimated to be 650 feet per second (approximately 195 meters per <br />second) based on correlations with blow count values. Saturated conditions were <br />assumed to exist at a depth of 8 feet due to the highest depth of ground water <br />encountered in our test hole. The following table shows the results of our liquefaction <br />analysis based on soils encountered and test results obtained in boring B2 (see Plate <br />No. 3), <br />Uf„SUEt'AC`dN:®N 1lGVAW <br />5i5 _ <br />ILayrerr ( depth <br />Factor of <br />probability of <br />Comments <br />Below ground <br />Safety based - <br />LigtoefEA6.11on <br />surface on <br />an MCFEER <br />hase;ad On Seed <br />feet) <br />rtiaetho dl- <br />et. al. aetiMID& <br />Low potential for liquefaction clue <br />049 <br />to clay soils and partially saturated <br />soil conditions. <br />I, <br />Low potential of liquefaction clue to <br />1.9.30 g;�r� <br />D;01 <br />relative density of sand and low <br />ground sulfate acceleration. <br />High probability of liquefaction clue <br />30-35 1 10.84 <br />®.34 <br />to relative density of saturated <br />sand. <br />High probability of liquefaction due <br />351-41.5 63 <br />CD,JcS <br />to relative density of saturated <br />sand. <br />Note 1: <br />A value less tnan 1.0 <br />malcates <br />uqueracclon Is premccea. <br />Note 2: <br />The closer the value <br />is to 1.0, <br />the more probable liquefaction becomes. <br />l"he darker shaded cells are shown in the table to emphasis those layers most prone to <br />the Fourth International Conference on Recent ArAances In Geolechnica/ Earthquake Enghheering and Sail Dynan s <br />and SymposRtm /n Honor of Professor W.D. slam Finn, San Dlego, Callfornla, Alarch 26-31, 2001, Paper No. 5PL"2 . <br />NEIL O. ANDERSON <br />AND ASSOCIATE"S <br />.e 9027ndrended n4ry. Lodl; GI 95240 <br />V007 Neff 0. Anderson 0 Assonetes, Inc. <br />