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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 (Ri) is a <br /> calculated parameter defined by 100f)q, and is used to Infer soil behavior type Generally- <br /> Cohesive soils (clays) <br /> • High friction ratio (Rf) due to small cone bearing (q,) <br /> • Generate large excess pore water pressures (u2) <br /> Cohesionless soils (sands) <br /> • Low friction ratio (RA 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, fs, and u2 In these situations, expenence, judgment, and an <br /> assessment of the pore pressure dissipation data should be used to infer the soil behavior <br /> type <br /> ZONE Qt/N SBT <br /> 1 2 Sensitive, fine greained <br /> 2 1 Organic materials <br /> 10D 9 3 1 Clay <br /> 4 15 Sof cia to day <br /> s 5 2 Clayey silt to siltyclay <br /> 6 2 5 Sand silt to clayey sift <br /> 7 3 Silty sand to sand silt <br /> 10 8 4 Sand to siltysand <br /> 9 5 Sand <br /> 10 6 Gravel sand to sand <br /> 11 1 Very stiff fine grained* <br /> 12 2 Sand to clayey sand* <br /> 1 1 2 3 4 5 T 8 *over consolidated or cemented <br /> FdcdM Imo ft Rf <br /> Figure SBT <br />