Influence of Curing under Stress on the Geomechanical Response of Cemented Iron Ore Mining Tailings Subjected to Distinct Effective Stress Paths

Abstract

The mining sector plays a significant role in the economic development of countries by contributing to their gross domestic product. Once the demand for commercialized ore grows, the mining industry looks for new technologies to boost exploration and manage residue disposal. One promising technique to dispose of these residues is dry stacking. This research investigates the behavior of cemented iron ore tailings (IOTs) that use unconfined compression strength (UCS) and triaxial testing. The UCS tests investigated different dosages of cement–tailings compacted blends. In addition, nine triaxial tests were carried out, where six were cured under atmospheric pressure, and three were cured under 300 kPa. Samples were sheared under mean effective stresses of 300 and 3,000 kPa. Both curing conditions were subjected to drained axial loading, constant mean effective stress (p′), and lateral unloading stress paths. The results indicate that the porosity/cement index (η/Civ) could control the mixtures’ UCS. The triaxial tests revealed the effective strength parameters stress dependence. Samples that were consolidated under high stress might experience bond breakage, which leads to a decrease in the friction angle and a tendency toward critical state conditions. No meaningful variation was observed between samples that were cured under stress and atmospheric pressure.