Drained probing triaxial tests on a weakly bonded artificial soil

The results of drained probing triaxial tests are presented for a weakly bonded artificial soil in which the stress space is probed by following different stress path directions. The bounding surface (failure envelope) was found to vary with stress path direction. The influence of the stress path direction on the development of tangential stiffness, strain contours and the position of yield is also demonstrated. The yield behaviour is examined by identifying a reduction in tangential stiffness. Three different yield loci are presented in the stress space, each of which corresponds to the stress path direction followed. The changes in yield loci due to different stress path directions are explained in terms of anisotropic breakage of the bonded structure. The limits between different zones of behaviour were found to rotate in correspondence to the stress path direction. The work demonstrates that the yield loci and the zones of behaviour for bonded soils are not unique but depend on the stress path followed.