Analysis And Design Of Slopes For Rajo Sur, An Open Pit Mine Next To The Subsidence Crater Of El Teniente Mine In Chile

E.Hormazabal, F. Rovira, M. Walker and C. Carranza-Torres
Monday, November 9, 2009
First presented: 
Proceedings of Slope Stability 2009. November 9-11, 2009. Universidad de los Andes, Santiago, Chile.
Published paper
Rock Mechanics

El Teniente Division of CODELCO is conducting a pre-feasibility engineering evaluation of Rajo Sur project in Chile. This project involves construction of an open pit to mine a copper deposit near the southern border of the caving subsidence crater high in the mountains above El Teniente mine. A geotechnical assessment is being carried out to evaluate the stability of the walls of the pit, particularly in sectors next to the subsidence crater, where the rock mass is of very poor mechanical quality. To evaluate the mechanical stability of the open pit, a series of geotechnical studies have been conducted. These studies have involved, among others, site investigations and slope stability analyses based on limit equilibrium and elastoplastic continuum approaches; they have also involved development of a complex threedimensional mechanical model to assess the influence of subsidence cracks and abrupt topography on the stability of the planned open pit walls (particularly in the southern boundary of the crater). This paper provides a general description of the geotechnical study carried out for Rajo Sur project, including geological and geotechnical characterizations of the site, slope stability analyses and proposed design angles for the pit walls.

Feature Author

Esteban Hormazabal

Esteban is a Civil Mining Engineer and holds a Master of Science (Geophysics) specialized in applied hydrogeology. He has 22 years of specific experience in geotechnical engineering, rock mechanics and geotechnical instrumentation, having worked in different mining and civil engineering projects.

Additionally, he is an expert in analysis and geomechanical design of underground mining and surface excavations using 2D and 3D numerical modelling, stability analysis and slope design in open pits and waste dumps.

He has led different and important open pit and underground mining projects in Chile, Colombia, Mexico, Peru, Argentina, Uruguay and Russia.

Esteban has several authored publications as well as being speaker at different national and international conferences. He is an active member of AusIMM and QP (Qualified Person).


Head of Rock Mechanics Services
Min Eng, MSc (Geophysics), MAusIMM, CRIRSCO
SRK Santiago
SRK Turkey