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The relationship between the microfabric and the engineering properties of weathered granite

  • Baynes F. J. 
  • Dearman W. R. 
Article

Summary

The results and conclusions of a microfabric study of weathered granites are related to a review of the engineering properties of weathered granites. The changes in engineering properties of granites induced by weathering are attributed to microfracturing, opening of grain boundaries and development of an intragranular porosity. The shear strength of granite weathered to an engineering soil is considered in detail. A model is developed, involving the microfabric of the clay weathering-product and extent of decomposition, to explain the typically high angles of friction shown by such material. Deformability is also considered.

Keywords

Shear Strength Pore Pressure Engineering Property Residual Soil Clay Matrix 

Relations Entre La Microstructure Et Les Propriétés Géotechniques D’un Granite Altéré

Résumé

On établit un rapport entre les résultats et conclusions d’une étude de la microstructure de granites altérés, et l’examen de leurs propriétés géotechniques. Les changements de propriétés géotechniques des granites lors de leur altération sont attribués à la microfracturation, à l’ouverture des surfaces de contact des grains et au développement d’une porosité intragranulaire. On examine en détail la résistance au cisaillement du granite altéré devenu un sol géotechnique. On développe un modèle qui fait intervenir la microstructure de l’argile d’altération et l’étendue de la décomposition, pour expliquer les grands angles de friction que l’on observe typiquement dans ce genre de matériau. On étudie aussi l’aptitude à la déformation.

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Copyright information

© International Assocaition of Engineering eology 1978

Authors and Affiliations

  • Baynes F. J. 
    • 1
  • Dearman W. R. 
    • 1
  1. 1.Engineering Geology Unit, Department of GeologyUniversity of Newcastle upon TyneUK

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