FIELD MEASUREMENTS ON MODEL PILE IN TWO CLAY DEPOSITS.

The piezo-lateral stress (PLS) cell is an in situ testing device that is capable of providing simultaneous measurements of the total horizontal stress, the pore pressure, and the shear stress acting on cylindrical pile shafts during the various stages in the life of a pile. PLS cell measurements obtained during penetration and subsequent soil consolidation in two clay deposits are presented herein and clearly show that clay sensitivity has an important effect on pile shaft behavior. Moreover, measurements are in reasonable agreement with predictions based on the strain path method that are significantly different from predictions obtained by means of the more popular cavity expansion method.