Piston core properties and disturbance effects.

Laboratory geotechnical data on piston cores for 31 sites on the mid-Atlantic Upper Continental Slope show the near-surface sediments vary from normally consolidated to somewhat overconsolidated clayey silts and silty clays of low to high plasticity. They also exhibit normalized behavior and their index property correlations with the effective-stress friction angle, the undrained strength ratio, and the compression index are reasonably consistent with existing knowledge. Because existing knowledge concerning disturbance effect suggests that in-situ preconsolidation stress values should lie between those derived from the triaxial and laboratory vane data, the preconsolidation stress values obtained from the consolidation data appear to be appreciably smaller than in-situ values. -from ASCE Publications Information