Mechanical Behavior of Cement-Stabilized Polymetallic Mine Tailings

This study investigates the mechanical response of mine tailings stabilized with 2–6% cement after different curing periods. The experimental program included one-dimensional oedometer tests, consolidated drained and undrained triaxial tests, and mineralogical and microstructural analyses using X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy to support the interpretation of the observed behavior. Results were interpreted within the critical state framework, with emphasis on the stress–strain response, the evolution of the stress ratio, and the behavior in the compression plane. Cement addition increased stiffness, yield stress, peak strength, and brittleness, mainly due to cement hydration and, to a lesser extent, due to pozzolanic reactions, given the typical characteristics of mine tailings. The curing period showed only a minor influence on the mechanical response, indicating that most cementation effects developed rapidly after mixing. Changes in the critical state parameters were observed in both the compression and q– $$p'$$ planes. For the untreated and 2% cement-treated specimens, critical state conditions were clearly identified. However, for higher cement contents, only apparent critical state trends could be inferred, as strain localization and incomplete destructuration limited the identification of well-defined critical state conditions. The apparent M decreased with increasing confining pressure, which suggests that cementation effects diminish at higher stress levels due to progressive destructuration during consolidation and subsequent shearing. These findings provide relevant insights into the behavior of cemented tailings and their various applications in mining engineering.