The low bearing capacity of clayey soils represents a recurrent challenge in infrastructure projects, commonly addressed through physicochemical stabilization using traditional additives. However, these methods often involve high costs and environmental impacts associated with material production and limited availability. This study evaluates the technical feasibility of using inert tailings as a stabilizing agent for clay soils. To this end, stabilization tests were conducted by incorporating tailings and a mortar composed of tailings and cement at dosages of 5%, 10%, 15%, and 20%, to assess their effect on soil behavior. The mixtures were characterized through physical tests, including Atterberg limits and soil classification according to the Unified Soil Classification System (USCS) and the American Association of State Highway and Transportation Officials (AASHTO), as well as mechanical tests such as California Bearing Ratio (CBR) and unconfined compressive strength. Among the tested dosages, the 15% mortar dosage showed the best performance, exhibiting mechanical behavior comparable to that of the soil stabilized with 15% cement. At this dosage, the soil–mortar mixture presented a liquid limit of 56%, plastic limit of 47%, and a plasticity index of 9%. The CBR increased from 5.1% (natural soil) to 15.4%, while the unconfined compressive strength reached 5.76 kg/cm 2 , representing an increase of 82%. These results demonstrate that tailings can be considered a technically viable and sustainable alternative for the stabilization of clayey soils. Furthermore, they provide a solid basis for optimizing dosages in future studies while promoting responsible management of mining waste.
Gaibor-Lombeida et al. (Wed,) studied this question.