Scientific Quarterly Journal of Iranian Association of Engineering Geology

Scientific Quarterly Journal of Iranian Association of Engineering Geology

A Study of Open-Pit Mine Wall Slope Using Rock Mass Classification Methods: A Case Study of Golbini 7 Bauxite Mine, Jajarm

Document Type : Original Article

Authors
1 Official Expert Organization, North Khorasan Branch
2 Official Expert Organization, Razavi Khorasan Branch
3 Rock mechanics expert, Iran Alumina Company
4 Department of Civil Engineering, Islamic Azad University of Roudehen
Abstract
Slope stability is a critical factor influencing both the economic viability and safety of open-pit mines. A fundamental prerequisite for its analysis is the empirical classification of the rock mass. These methods are extensively employed during preliminary and feasibility studies and are frequently integrated into final designs. The primary objectives of such classifications are to categorize the rock mass based on behavior and quality, generate quantitative guidelines for slope engineering, and enhance professional judgment and collaboration in design processes.



This study focuses on the Golbini 7 Jajarm mine, aiming to classify its rock mass and determine the optimal single-bench and overall pit wall slopes using empirical techniques. Field investigations involved ten engineering geological scanlines totaling 432 meters. Kinematic analysis using Dips software established optimal single-bench slopes of 65 degrees for the north wall (Shamshak formation) and 47 degrees for the south wall (Elika formation). Subsequently, a comparison of results from the RMR, MRMR, and Q-Slope classification systems led to recommended overall slope angles of 47 and 49 degrees for the Shamshak and Elika walls, respectively. The findings confirm that the MRMR method offers reliable solutions for shallow-depth mines. However, for determining the final slope in deep mines, empirical analyses must be supplemented with limit equilibrium and numerical modeling methods to ensure comprehensive stability assessment.
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Volume 18, Issue 1
Spring 2025
Pages 49-59

  • Receive Date 22 February 2025
  • Revise Date 12 November 2025
  • Accept Date 01 December 2025