Stress–strain responses and yielding characteristics of a municipal solid waste (MSW) considering the effect of the stress path

Abstract

The stress–strain behavior of municipal solid waste (MSW) is important to predicate the deformation of MSW in landfills. Triaxial tests under K 0 consolidation with different stress paths were carried out on MSW samples. Test results of the MSW are compared with that of clays in terms of stress–strain responses and coupled components. In triaxial extension tests, the stress–strain responses of MSW are similar to that of clays reported in literature. In triaxial compression tests, however, the stress–strain responses of the MSW are different from that of the clays, especially a progressively increasing upward curvature is observed at large strains without reaching a peak stress state on the compression stress paths of $$\Delta \sigma_{3}^{{\prime }}$$ ≥ 0. For the stress paths Δq = 0 and Δp′ < 0, although the volume of MSW specimen is expanded, the axial strain is increased, which is different from the behavior of the clays. Compared to the clays, the cross-coupling responses of the MSW are more pronounced. The most variations for shear and bulk modulus of MSW occur in q unloading range and p′ unloading range, respectively. The yield surface of MSW in p′ − q space is obtained and the fibrous reinforcement within specimens is confirmed in this study. Consequently, the stress–strain responses, shear and bulk modulus, and yielding characteristics of MSW are all closely related to the stress path.