Scalping techniques in geomechanical characterization of coarse granular materials

Authors

  • Leonardo Dorador EGSciences SpA, Chile
  • Felipe A. Villalobos Universidad Católica de la Santísima Concepción, Chile image/svg+xml

DOI:

https://doi.org/10.4067/S0718-28132020000200024

Keywords:

Coarse granular materials, Scalping method, Geotechnical characterization, Size-scaling, Shear strength

Abstract

The study of materials with large particle size has been a great challenge in geotechnical engineering. Despite the current work around the world using coarse-grained materials CGM in rockfill dams and mining waste rock dumps, for instance the geotechnical characterization of these materials is still an important issue in geotechnical engineering practice which deserve more research. There are standards covering CGM in a few particular applications and scaling methods have been proposed to deal with large particle sizes. However, scaling methods are appropriate only under certain conditions. The scalping techniques consist in a simple approach for the geotechnical characterization of CGM. In this article, the scalping techniques analysed are divided in: the scalping method, the matrix method and the scalping/replacement, which are studied in detail in terms of its effectiveness, focusing on the geomechanical characterization of CGM. As a main conclusion, these three techniques are limited in its use under small scalping ratios (3 < r < 8) which is the ratio of maximum particle size of both original and scalped gradation. Finally, recommendations for the use of percentages and ratio of scalping are provided.

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Published

2020-12-01

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How to Cite

Scalping techniques in geomechanical characterization of coarse granular materials. (2020). Obras Y Proyectos, 28, 24-34. https://doi.org/10.4067/S0718-28132020000200024