... standards are notavailable, other widely accepted detailedguidelines, such as Sabatini, et al. (2002),AASHTO Manual on Subsurface Investigations(1988), Arman, et al. (1997) and Campanella(1994), ... average value and variability, theengineer may perform a sensitivity analysis usingaverage parameters and a parameter reduced by onestandard deviation, i.e., “mean minus 1 sigma", or a lower ... N-valueSoil TypeEs(ksi)Silts, sandy silts, slightly cohesivemixturesClean fine to medium sands and slightly silty sandsCoarse sands and sands withlittle gravelSandy gravel and gravels0.056...