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On the anisotropy of the athenian schist and its relation to weathering

  • Zissis Papadopoulos
  • Paul Marinos
Article

Abstract

The influence of schistosity on the strength of the “Athenian schist” when considering the anisotropy index as derived from point load testing, is examined. Furthermore, the influence of the degree of weathering upon the anisotropic characteristics of the schist is also investigated. Anisotropy index values are found to range between just below 1 and 3 approximately. Low anisotropy values correspond to rock in its very weathered state, higher values are related to less weathered material and there is also a trend for anisotropy to decrease towards sound rock conditions.

Point load testing proved a reasonable means for assessing those rock characteristics associated with strength, anisotropy and weathering state, while slake durability testing showed considerable insensitivity towards the latter.

Keywords

Point Load Triaxial Test Weathered Type Deep Excavation Point Load Strength 

L'anisotropie des schistes d'athènes et ses liaisons avec l'altération

Résumé

L'article traite de l'influence de la schistosité des “schistes d'Athènes” sur la résistance, en se basant sur les résultats du ≪point load test≫. Le rôle du degré d'altération de la roche sur l'anisotropie est aussi examiné.

Les indices anisotropiques varient entre 1 et 3. Les faibles valeurs correspiondent à une altération pronconcée, les valeurs les plus élevées correspondent à un état d'altération médiocre, tandis qu'on note une tendance à la diminution, de nouveau, vers les schistes les plus sains. Le ≪point load test≫ s'avère très raisonnable si on veut classifier la roche en foction de sa résistance, son anisotropie et son état d'altération.

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Copyright information

© International Association of Engineering Geology 1992

Authors and Affiliations

  • Zissis Papadopoulos
    • 1
  • Paul Marinos
    • 1
  1. 1.Geotechnical DivisionNational Technical University of AthensGreece

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