Tunnel alignment for the cortaderal hydroelectric scheme, chile

  • Nagel Karl-Heinz
  • Thomas Arturo


The regional geology of the Cortaderal Hydroelectric Scheme in Chile and its decisive influence on the alignment of 37.4 km of waterways is presented. A solution with optimum use of hydropotential and possible most favorable tunnelling conditions was established. A procedure including rock mass classification and subsequent study of alternatives was used. Results are given for the Geomechanics (RMR) system for 10 geological sub-units as well as the signification and support recommendations for the encountered rock types.

With its totally changed layout, the Cortaderal Project is considered today among the most attractive hydroelectrical development under investigation in Chile.


Rock Burst Intrusive Rock Rock Mass Rating Rock Cover Tunnel Diame 

Étude du tracé des tunnels pour le complexe hydroélectrique de cortaderal, chili


L'article présente la géologie régionale du complexe hydroélectrique de Cortaderal, au Chili, et son influence sur le tracé des 37,4 km de tunnels. On a mis au point une solution combinant une utilisation optimale du potentiel hydraulique et des conditions de foration des tunnels les plus favorables possibles. La méthode utilisée inclut une classification des massifs rocheux puis une étude des variantes. Les résultats sont présentés dans le système RMR pour 10 unités géologiques et complétés par des recommandations pour chaque type de roche traversé.

Après la révision complète du projet, le complexe de Cortaderal est considéré maintenant comme l'un des complexes hydroélectriques les plus intéressants en cours d'étude au Chili.


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Copyright information

© International Association of Engineering Geology 1989

Authors and Affiliations

  • Nagel Karl-Heinz
    • 1
  • Thomas Arturo
    • 2
  1. 1.Electrowatt Engineering Services Ltd.Zurich
  2. 2.Santiago de Chile

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