ABSTRACT
The expansion of the drilled shaft during the set up of the concrete parallels the expansion of the pressuremeter. Therefore in order to evaluate the horizontal stress generated by the expansion of the concrete it is appropriate to use the preboring pressuremeter. The pressuremeter is inflated to a strain level which matches the anticipated strain level created by the expansive concrete. The pressuremeter test results can be used in conjunction with the finite element analysis. The pressuremeter is one of the few in situ tests which allow testing rocks and shales in situ. During testing, difficulties may arise when the rock layers are interbedded with softer horizontal clay layers. In the design rules for piles which bear into rock layers, particular attention must be paid to rock layers interbedded with softer horizontal clay layers.
