Stress history and sampling disturbance effects on monotonic and cyclic responses of overconsolidated Bootlegger Cove clays

This paper examines the influence of reproducing the stress history of a natural soil deposit during laboratory reconsolidation on the subsequent response and behavior of heavily overconsolidated Bootlegger Cove Formation (BCF) clays under both monotonic and cyclic loadings. The results are compared with a conventional reconsolidation technique wherein a specimen is directly K₀-reconsolidated to the in situ effective stresses, and no stress history of the overconsolidated soil deposit is reproduced. Monotonic and cyclic experiments under triaxial conditions were conducted and their results compared in terms of stress-strain-strength responses with emphasis on shear stiffness degradation, to show the significant difference in the responses between the stress-probe sets. Additionally, comparison with field and in situ measurements are presented to validate procedures, judge the accuracy of the experiments, and evaluate the effects of tube sampling.