Geotechnical Characterization of Iron Tailings from a Mine in South America using the Seismic Cone Penetration (S-CPTu) and Laboratory Tests

ABSTRACT: This paper summarizes and discusses the results from the Seismic Cone Penetration Test (S-CPTu) and Laboratory Test of iron tailings disposed of at different times, classified as either old or new tailings. This temporal variation generated differences in undrained strength, stiffness, and microstructure. These tailings are discretized based on the Soil Behaviour Type Index (Ic) to review contractive and dilative behaviour and identify possible zones of brittleness using different interpretation approaches. This characterization will be complemented with the mineralogical composition information obtained from X-ray diffraction tests to evaluate the presence of microstructures and their influence on the contractive-dilative response of the tailings. A discussion of some limitations of conventional S-CPTu classification and empirical correlation methods, when applied to this type of material, is presented in this paper, along with a framework for interpretation and classification.