skip to main content
Idioma:
Primo Search
Clear Search Box
Search in: Busca Geral
Busca Avançada
Busca por Índices

Variability of the undrained strength of the plastic tailings from the Germano dam in Mariana, Brazil

De Bona Becker, Leonardo ; Salgueiro de Aguiar, Ana Luiza ; Alvarenga Lacerda, Willy

Geomechanics and geophysics for geo-energy and geo-resources., 2024-12, Vol.10 (1), p.1-17, Article 25

Cham: Springer International Publishing

Texto completo disponível

Citações Citado por
  • Título:
    Variability of the undrained strength of the plastic tailings from the Germano dam in Mariana, Brazil
  • Autor: De Bona Becker, Leonardo ; Salgueiro de Aguiar, Ana Luiza ; Alvarenga Lacerda, Willy
  • Assuntos: Clay minerals ; CPTu ; Dam stability ; Dams ; Energy ; Engineering ; Environmental Science and Engineering ; Foundations ; Geoengineering ; Geophysics/Geodesy ; Geotechnical Engineering & Applied Earth Sciences ; Groundwater table ; Hydraulics ; Iron ores ; Liquefaction ; Mine tailings ; Mine wastes ; Mineralogy ; Original Article ; Plastic tailings ; Plastics ; Sand ; Silt ; Stability analysis ; Strength ; Tailings ; Thickness ; Undrained strength ; Vane test ; Variability ; Water levels ; Water table
  • É parte de: Geomechanics and geophysics for geo-energy and geo-resources., 2024-12, Vol.10 (1), p.1-17, Article 25
  • Descrição: Mining tailings may be divided in non-plastic (sand, silty sand, or sandy silt tailings) and plastic (fine tailings, usually mixtures of silt and clay-sized particles). The understanding of the behavior of these materials is a great geotechnical challenge because of their wide variations in mineralogy, physical–chemical, and geotechnical characteristics. Sand tailings have been widely studied in the last decades because they are often susceptible to liquefaction, and they usually constitute the beach of the tailings dam which is the most important zone for stability analysis in upstream dams. However, the study of the characteristics and the strength of the plastic tailings is also important since layers of plastic tailings are sometimes found in the midst of the sand tailings. The aim of this article is to study the normalized undrained strength ratio ( s u / σ′ v ) of plastic tailings of the Germano dam in Mariana, Brazil, and to present a criterion developed for their identification. The method consisted of analyzing and scrutinizing Piezocone (CPTu), Field Vane (FV) tests, and the water levels. An extensive review of the iron ore plastic tailings properties was also performed. A total of approximately 900 occurrences of plastic layers were analyzed. The results included the discovery of perched water tables and significant vertical downward flow in some locations. The conclusion is that s u / σ′ v histograms are well fitted by lognormal distributions and the layer thickness influences the undrained strength. Moreover, the strengths are relatively low (for example, s u / σ′ v  = 0.11 on average for plastic layers with thickness of 1.0 m or more). Article highlights The distribution of the s u /σ′ v ratio of the plastic tailings from the Germano dam is lognormal. The peak normalized undrained strength of plastic tailings is significantly inferior to the peak normalized undrained strength of sand tailings indicated in the literature. The thicker a layer of plastic tailings is, the lower are its s u /σ′ v and its variability. The consideration of the same set of undrained strength parameters for representing interspersed layers of plastic and sand tailings in stability analysis does not seem appropriate to the plastic tailings of Germano dam since their normalized undrained strength is significantly lower than the sand tailings
  • Editor: Cham: Springer International Publishing
  • Idioma: Inglês
Voltar para lista de resultados

  • Realização: ABCD-USP USP   Logos de Redes Sociais: Freepik

Buscando em bases de dados remotas. Favor aguardar.