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EGG Cone Penetration Test Data & Interpretation <br /> Soil behavior type and stratigraphic interpretation Is based on relationships between cone <br /> bearing (q,), sleeve friction (f,), and pore water pressure (u2) The friction ratio (Rf) is a <br /> calculated parameter defined by 100f,1q, and is used to infer soil behavior type Generally <br /> Cohesive soils (clays) <br /> • High friction ratio (Rf) due to small cone bearing (qJ <br /> • Generate large excess pore water pressures (u2) <br /> Cohesionless soils (sands) <br /> • Low friction ratio (Rf) due to large cone bearing (q,) <br /> • Generate very little excess pore water pressures (u2) <br /> A complete set of baseline readings are taken prior to and at the completion of each <br /> sounding to determine temperature shifts and any zero load offsets Corrections for <br /> temperature shifts and zero load offsets can be extremely important, especially when the <br /> recorded loads are relatively small In sandy soils, however, these corrections are generally <br /> negligible <br /> The cone penetration test data collected from your site is presented in graphical form in <br /> Appendix CPT The data includes CPT logs of measured soil parameters, computer <br /> calculations of interpreted soil behavior types (SBT), and additional geotechnical parameters <br /> A summary of locations and depths is available in Table 1 Note that all penetration depths <br /> referenced In the data are with respect to the existing ground surface <br /> Soil interpretation for this protect was conducted using recent correlations developed by <br /> Robertson et al, 1990, Figure SBT Note that it Is not always possible to clearly identify a soil <br /> type based solely on q,, f, and u2 In these situations, experience, judgment, and an <br /> assessment of the pore pressure dissipation data should be used to infer the soil behavior <br /> type <br /> 10D0 <br /> ZONE Qt/N SBT <br /> 1 2 Sensitive, fine grained <br /> 2 1 Organic materials <br /> 100 8 3 1 Clay <br /> 4 1 5 Silty clay to clay <br /> 5 2 Clayey silt to silty clay <br /> 6 2 5 Sandy silt to clayey silt <br /> 7 3 Silty sand to sandy silt <br /> 10 8 4 Sand to silty sand <br /> 9 5 Sand <br /> 10 6 Gravely sand to sand <br /> 11 1 Very stiff fine grained* <br /> 12 2 Sand to clayey sand* <br /> 1 0 1 2 3 4 5 B 7 8 *over consolidated or cemented <br /> Mcdon Ratlo (%), Rf <br /> Figure SBT <br />