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A General Solution for Estimating the Safety Factor of Bimslopes

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Abstract

Bimslopes are slopes underlain by block-in-matrix rocks/soils (bimrocks/bimsoils), which are heterogeneous geomaterials with complex behavior. Abundant uncertainties in the mechanical, spatial, and geological nature of bimslopes make it difficult to estimate stability conditions of bimslopes. In this paper, some factors affecting the stability of bimslopes are investigated using the finite-element method. The main contributory factors include Volumetric Block Proportion (VBP), the inclination of blocks, and the strength of matrix/block interfaces. By performance of sensitivity analysis on these factors, a statistically significant equation was obtained to estimate the safety factor of bimslopes using the multivariate regression method. The influence of block configurations and groundwater levels on the stability of bimslopes was then investigated to more confidently use the multivariate equation. Finally, to check the validity of procedures presented in this paper, a real failed bimslope in the Sungun mine (Iran) was investigated. The acceptable results from the Sungun analysis demonstrated the safety factor of bimslopes can be estimated using the practical solution presented in this paper.

Highlights

  • Development of more than 1300 numerical models to analyze the key factors affecting the stability of block-in-matrix slopes (bimslopes).

  • Investigation of the influence of volumetric block proportion, the inclination of blocks, and strength of matrix/block interface on the safety factor of bimslopes.

  • Consideration of the substantial uncertainties affecting the analysis of bimslopes.

  • Presentation of the results of research in the form of applied schemes and tables.

  • Provision of a practical procedure and equation for estimating the safety factor of bimslopes.

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Data Availability

The analyzed data were obtained through modeling done by the authors, and the data of the case study were obtained from field mapping and a related report from the Sungun mine.

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Authors and Affiliations

  1. School of Mining Engineering, College of Engineering, University of Tehran, Northern Kargar Street, Tehran, Iran

    Emad Khorasani

  2. Thurber Engineering Ltd., Vancouver, Canada

    Mehdi Amini

  3. Terraphase Engineering, Oakland, CA, 94612, USA

    Edmund Medley

  4. RahsazTarh Consulting Engineers, Tehran, Iran

    Sadegh Tarigh Azali

  5. School of Minerals and Energy Resources Engineering, UNSW, Sydney, Australia

    Mohammad Farouq Hossaini

Authors
  1. Emad Khorasani
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  2. Mehdi Amini
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  3. Edmund Medley
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  4. Sadegh Tarigh Azali
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  5. Mohammad Farouq Hossaini
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Contributions

The research documented in this paper was performed and written by EK and MA. EM reviewed the paper in detail. Field analysis of the case study was performed by STA. MFH provided key guidelines in the research process.

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Correspondence to Emad Khorasani.

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Khorasani, E., Amini, M., Medley, E. et al. A General Solution for Estimating the Safety Factor of Bimslopes. Rock Mech Rock Eng 55, 7675–7693 (2022). https://doi.org/10.1007/s00603-022-03050-z

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  • DOI: https://doi.org/10.1007/s00603-022-03050-z

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