Cyclic behaviour of stabilized tailing sand with polymer-based additives: Grain-scale study

The application of polymer-based stabilizers can provide an alternative solution in the enhancement of the mechanical properties of soils and the stability of geo-systems. A large number of works in the geotechnical engineering field have studied various types of polymer-based stabilizers, however less attention has been given to the fundamental study of this type of ground improvement at the level of grain and grain contacts. In this study an investigation is presented examining the behaviour of tailing sand grains stabilized with a polymer-based material and the study is directed in grain-scale experiments performing both monotonic and cyclic tests on pairs of particles untreated and treated with the stabilizing agent. The experiments are performed using advanced micromechanical-based techniques, and the basic properties examined are related with the frictional response and the energy dissipation of specimens composed of the grain-to-grain configuration. A laboratory method is developed for this purpose to coat in-situ the grains with the polymer and all the samples were subjected to multiple cycles of loading. The results from the study show promising applications in terms of stabilization of the tailing sand, as the micromechanical parameters examined in this work are firmly correlated with the bulk behaviour of the material. Thus, the specific technique which is applied in this study at the small-scale, can provide a promising direction for future works with multi-scale analyses, from laboratory element-size samples to physical model and in-situ experimentation, so that to enhance the long-term performance of tailing dams mitigating risks associated with potential failures. © Engineers Australia 2021