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Cyclic liquefaction induced by seismic loading from earthquakes is a major concern for countries with active mining industries and moderate seismicity, such as Peru, Chile, and the USA. Cyclic liquefaction is more likely to induce flow failure as compared to other failure modes, and has been associated with a large portion of failures in seismic countries like Chile. Chile is a leading provider of copper and lithium to the global market, and the country’s ability to sustain such a large mining sector could be hindered by its ability to safely store its tailings. Mine tailings have been shown to have unique mechanistic responses dissimilar to those of traditional soils (i.e., sands and clays). Much of engineering practice relies on techniques and procedures developed from data derived from sands and clays. As such, our understanding of the cyclic behavior of mine tailings needs continued research interest to extract new insights into their unique behavior. This paper utilizes a recently developed database focused on the cyclic response of mine tailings to highlight some insights into their peculiar behavior. Specifically, their unique range of material properties and resulting liquefaction curves, the applicability of existing factors in the liquefaction assessment of these materials as compared to sands, and a comparison of in-situ and laboratory-derived cyclic resistances are showcased.
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A novel experimental database on the cyclic response of mine tailings
Understanding the cyclic response of mine tailings is key for areas with moderate to high seismicity and an active mining industry (e.g. the United States, Peru, and Chile). However, assessing the cyclic response of mine tailings still relies on procedures and correlations developed for natural soils (i.e. sands and clays). This is due to information on the cyclic response of mine tailings being rather scarce compared to natural soils. Hence, it remains unclear if more efficient approaches can be implemented. This study presents an experimental database focused on the cyclic response of mine tailings compiled from various sources. The database is organized considering three classes, where all three contain cyclic simple shear (CSS) information. Class A also includes triaxial (Tx) and cone penetration testing (CPTu) information, Class B has Tx or CPTu information, and Class C contains no additional information beyond CSS. Most materials belong to Class A. It is worth noting that Class C (only cyclic information) is comparable with most databases for natural soils, hence highlighting the uniqueness of our database. In total, the database contains 129 CSS tests on 20 materials that represent a broad range of mine tailings. Thirteen materials belong to Class A, 5 to Class B, and 2 to Class C. In discussing the database, key information (e.g. the range of liquefaction resistance curves) is shared. In addition, potential assessments that can be conducted with the database are illustrated. The study closes by presenting the database organization and discussing potential uses. The database is available under the following DOI: https://doi.org/10.17603/ds2-1k0a-dt17
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- Award ID(s):
- 2145092
- PAR ID:
- 10486777
- Publisher / Repository:
- SAGE Publications
- Date Published:
- Journal Name:
- Earthquake Spectra
- Volume:
- 40
- Issue:
- 1
- ISSN:
- 8755-2930
- Format(s):
- Medium: X Size: p. 828-846
- Size(s):
- p. 828-846
- Sponsoring Org:
- National Science Foundation
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