Undrained compression tests under plane strain condition were simulated for cohesive soils by the soil-water coupled finite element analysis based on finite strain. This was done to investigate the mechanism from the initiation of strain localization to the formation of shear bands and to estimate the slip surface. The soils examined exhibited plasticity indices of 10, 30, and 50.
The mechanism from the initiation of strain localization to the formation of the shear band was demonstrated by this analysis. The results suggest that estimation of the slip surface is possible, and that differences in plasticity index influence the mechanism of shear band formation. The inintiation of strain localization occurs at a smaller axial strain as a result that plasticity index decreased.