Cyclic Strengths Compared for Two Sampling Techniques

Two distinctly different field sampling and laboratory preparation procedures, used to obtain similar sand samples for cyclic testing, are documented. A comparison of the cyclic strengths of the samples is presented together with examinations of optimum techniques in undisturbed sampling and sample preparation. One procedure used included Pitcher barrel sampling, followed by laboratory trimming by mechanical extrusion into smaller diameter brass molds. The second procedure included hand-carved block sampling followed by either further hand-trimming, freezing and trimming, or saturation and trimming. The block-sampling and hand-trimming preparation procedure resulted in significantly higher cyclic strengths corroborating the concept that disturbance effects can cause major reductions in the cyclic strength of dense sand samples.