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EGG <br /> 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 (u,). The friction ratio (Rf) is a <br /> calculated parameter defined by 100f1q, 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 (qJ <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 /> �.r <br /> Soil interpretation for this project 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 qG, 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 /> loco <br /> 10 � ZONE Qt/N SBT <br /> f2• <br /> 1 2 Sensitive, fine grained <br /> �8 2 1 Organic materials <br /> '^ 3 1 Clay <br /> 4 1.5 Silty clay to day <br /> z r 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 Grave!y sand to sand <br /> 11 1 Very stiff fine grained* <br /> 12 2 Sand to clayey sand* <br /> 1 *over consolidated or cemented <br /> 0 1 2 3 4 5 8 7 B <br /> Friction Ratio (96), Rf <br /> Figure SBT <br />