A proposed weathering classification for basalts and their engineering properties (Turkey)

  • Tuğrul A. 
  • Gürpinar O. 


Most of the volcanic rocks widespread in Turkey are basalt. The effect of weathering processes on the physical and mechanical properties of this type of rock is important. To assess these properties and relations to each other, a study was undertaken in the Niksar region. A detailed investigation was carried out on basalts in the road cuttings of the Niksar ring road and Ünye-Akkuş-Niksar highway alignments.

A new classification system for basaltic rocks which are substantially influenced by weathering is proposed. The basic engineering properties of the basalt representing each weathering grade were determined. The properties tested are dry density, porosity, coefficient of permeability, uniaxial compressive strength, tensile strength and Young’s modulus. Interrelationships were determined for all test results. It is concluded that there is a substantial degradation in the engineering properties of the rock beyond a specific degree of weathering.


Olivine Rock Mass Uniaxial Compressive Strength Residual Soil Basaltic Rock 

Proposition d’une classification de l’altération des basaltes et étude de leurs propriétés géotechniques (Turquie)


La majorité des roches volcaniques en Turquie sont des basaltes. L’altération contrôle les propriétés physiques et mécaniques de ces roches. Nous avons choisi la série basaltique de l’Eocène a Niksar et nous avons étudié ses caractéristiques d’altération. La zone d’étude se situe sur la route périphérique de Niksar et sur la route nationale Ünye-Akkus,-Niksar.

Le but de ce travail est d’utiliser une classification d’altération des basaltes et de déterminer leurs propriétés géotechniques : densité, porosité, perméabilité, résistance en compression, résistance à la traction et module de Young. Les études ont montré qu’il y a des différences marquantes entre les degrés d’altération et qu’elles sont proportionnelles.


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Copyright information

© International Assocaition of Engineering eology 1997

Authors and Affiliations

  • Tuğrul A. 
    • 1
  • Gürpinar O. 
    • 1
  1. 1.Geological Eng. Dept., Faculty of Eng.Istanbul UniversityIstanbulTurkey

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