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• <br /> From the dissipation plots,simply read the dissipation depth and dissipated pressure for the <br /> values to plug into the equation above. On the plots, pore pressure(psi) is on the abscissa and log <br /> time(seconds) is on the ordinate. <br /> • SamMine Description <br /> Geoprobe® brand Dual Tube Sampling Systems are efficient methods of collecting continuous <br /> soil cores with the added benefit of a cased hole. Dual tube sampling uses two sets of probe rods <br /> to collect continuous soil cores. One set of rods is driven into the ground as an outer casing(2.2 <br /> or 3.25 inches in diameter). These rods receive the driving force from the hammer and provide a <br /> • sealed hole from which soil samples may be recovered without the threat of cross contamination. <br /> The second, smaller set of rods are placed inside the outer casing.The smaller rods hold a sample <br /> liner in place as the outer casing is driven one sampling interval.The small rods are then retracted <br /> to retrieve the filled liner. Soil samples are collected in 1.85-inch diameter or 1.125-inch <br /> diameter clear PVC sample sheaths. <br /> • Interpretations <br /> Soil behavior type(SBT), SPT N60 energy ratio,undrained shear strength,OCR,and unit <br /> weights are calculated and/or are interpretations generated by the CPT-Pro software based on <br /> empirical relationships derived in the following references; <br /> P.K. Robertson,R.G.Campanella,D. Gillespie,and J.Greig, 1986, Use of Piezometer Cone Data, <br /> • Proceedings of the ASCE Specialty Conference In Situ '86: Use of In Situ Tests in Geotechnical <br /> Engineering;pp. 1263-1280. <br /> P.K. Roberston, 1990, Soil Classification Using the Cone Penetration Test,Canadian Geotechnical <br /> Journal,27(1),pp. 151-158. <br /> • T. Lunne,P.K. Robertson,and J.J.M. Powell, 1997,Cone Penetration in Geotechnical Practice, <br /> Taylor and Francis Publishing. <br /> CPT Inc. makes no recommendation on which soil behavior type analysis is"most-correct". The <br /> engineer should be aware of the limitations of using CPT data to derive soil behavior type and <br /> other engineering parameters and is encouraged to review the above references to better <br /> • understand the applicability and limitations of CPT data. It is sometimes not possible to <br /> determine soil type based solely on tip resistance,sleeve friction, and dynamic pore pressure <br /> response,and confirmatory samples may be required. <br /> Please do not hesitate to contact CPT Inc. if you have questions. <br /> • Sincerely, <br /> John Rogie <br /> President <br /> • California Push Technologies,Inc. <br /> • <br /> CPT Inc.methods descriplim.doc June 25,2008 <br /> • <br />