Comparisons of Two Reconstitution Methods for Clay Specimens

This paper compares laboratory element test results on kaolin clay reconstituted by two different methods. One method was to consolidate a slurry in a large consolidation box producing a block sample that could be cut into triaxial-sized specimens. This produced consistent specimens near the liquid limit. The other method was to use a pug mill, a device used to mix, de-air and extrude clay that can be used for pottery. Consistent specimens with a water content below the liquid limit could be prepared in this way. The testing program presented herein included one-dimensional incremental loading oedometer and undrained triaxial compression loading tests on the two reconstituted specimen types. The results show that the two reconstitution methods significantly influence the test results because of kaolin particle arrangement. The slurry-based specimens show more compressibility and contractive shearing behavior while the pug mill specimens show less compressibility and somewhat dilatant shearing behavior.