ABSTRACT
This paper is the first part of a study that assesses the influence of undulations on the effective stress across a shear zone during rapid shearing. A simple model is proposed to predict the magnitude of the pore water pressures which may be generated when shearing occurs along non-planar shear surfaces. The model assumes that the non-planar shear surface can be divided into a zone of positive gradient (where compression is occurring) and a zone of negative gradient (where swelling is taking place). In the compression zone, the change in effective stress is obtained from one-dimensional consolidation theory. In the swelling zone, two solutions are considered; firstly, a “free swell model” (where shear zone separation may occur), and secondly, a “forced swell model” (where separation is not permitted). The merits of the two assumptions are considered, and subsequently the free swell model is proposed as the more accurate technique.
