Engineering classification and index properties of a weathered granite

  • Irfan T. Y. 
  • Dearman W. R. 


A comprehensive range of classification, or index, and engineering design tests have been carried out on the seven stages of weathering of rock material recognised in the Hingston Down granite from east Cornwall, England. Interrelationships have been determined for all test results. It is concluded that the quick absorption, Schmidt hammer and point load strength tests are reliable and simple field tests for the determination of a quantitative weathering index. This quantitative weathering index can be related to visual determination of weathering stages of rock material, combinations of which can be used to categorize distinct weathering grades in the rock mass.


Rock Mass Uniaxial Compressive Strength Rock Material Effective Porosity Index Test 

Classification Geotechnique et Proprietes Mesurables d’un Granite Altere


Une suite complète de classification, ou index, et des essais techniques ont été effectués sur les sept phases d’altération du matériau rocheux reconnues dans le granite de Hingston Down à l’est de la Cornouailles (Angleterre). Les interrelations ont été déterminées pour tous les résultats des essais. On conclut que trois essais — absorption rapide, scléromètre Schmidt, et essai de résistance à une charge ponctuelle — sont des essais de terrain simples et fidèles pour la détermination d’un index quantitatif d’altération. Celui-ci peut être mis en relation avec la détermination visuelle des phases d’altération du matériau rocheux, dont les combinaisons peuvent être utilisées pour caractériser des degrès distincts d’altération dans la masse rocheuse.


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Copyright information

© International Association of Engineering Geology 1978

Authors and Affiliations

  • Irfan T. Y. 
    • 1
  • Dearman W. R. 
    • 1
  1. 1.Engineering Geology Unit, Department of GeologyUniversity of Newcastle upon TyneEngland

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