Lower and upper limits of layered-soil strength

This paper presents an approach to determine the lower and upper limits for failure criteria of layered soils that have periodic structure. Particular functional forms are proposed for multilayered soil samples consisting of two periodic constituents. It was found that the upper limit of failure criterion is uniquely determined by volume fraction and strength characteristics of each constituent, whereas the lower limit is affected by the interaction between constituent layers, which in turn depends on the deformation characteristics. An important observation is that an upper limit can only be reached for certain stress paths. The directional dependency of layered soil strength was examined within the context of the proposed approach.