ASSESMENT OF DOLOMITE WALL FAILURES IN THE 6TH GOLBINI JAJARM BAUXITE MINE BY USING SMR CLASSIFICATION SYSTEM

7th International Scientific Conference - SGEM2007, www.sgem.org, SGEM2007 Conference Proceedings/ ISBN: 954-918181-2, June 11-15, 2007

ABSTRACT

The stability problems in 73 meters height of dolomite wall cause to starting an
empirical estimation for early step of slope optimization. In this paper, three
rock classification systems (RQD, RMR and SMR) are utilized for assessment of
dolomite wall failures in the 6th Golbini Jajarm bauxite mine. The SMR (slope
mass rating) geo-mechanics classification system, is adaptation of RMR (rock
mass rating) for slopes. In first step, joint study and site investigation carried
out for RQD (rock quality designation) and RMR determination. The results
of these studies show four major discontinuities that contains three joint sets
and one bedding plane. Second step was laboratory tests and determining
groundwater condition that can be used to obtain the RMR parameters values.
The UCS (unconfined compressive strength of intact rock material) of dolomite
specimens is determined with uniaxial compressive strength laboratory tests.
Finally, the classification of rock mass, description of classes, probability of
failures and suggested support methods are determined according SMR values
in two critical sections, southern west and southern east walls with total height
of 155 meters, and two failure conditions, plane and toppling failure. Final
results describe the hazard of big planar or soil-like failures, in both critical
sections. It seems that Re-excavation on current 73 meters slopes must be
applied, for stability of 155 meters height of pit limit southern wall.

Keywords: Slope stability, Jajarm bauxite mine, rock classification systems.