Paper contribution

Integrated Workflow for Bench-Berm Design Optimisation and Reconciliation

Felipe Sanz

Proceedings
EUROCK 2026
Pages
827-832
Submitted
28 January 2026
Accepted
15 June 2026
Published
12 August 2026

Summary

Abstract

Bench-scale performance represents a critical component of geotechnical risk management in open-pit mining because structurally controlled backbreak and operational overbreak directly influence effective berm retention, rockfall containment capacity, and operational safety. However, uncertainty commonly exists between intended bench geometries and actual as-built conditions due to limitations in structural interpretation, persistence estimation, and blasting disturbance characterization, particularly during early project stages. This paper presents an integrated and iterative workflow for progressively refining bench-scale engineering interpretation through reconciliation between structural characterization, block formation simulation, and observed operational performance. The workflow was applied across multiple open pit projects and different stages of pit development, ranging from conceptual greenfield studies to operational final wall conditions. The methodology integrates geological interpretation, borehole data, surface structural mapping, laboratory testing, bench-scale block formation simulation, and photogrammetry-based reconciliation of as-built bench performance. The study demonstrates that representative engineering persistence and operational blasting conditions exert dominant controls on structurally controlled backbreak and effective berm performance. Comparison between simulated and observed bench conditions provided a practical basis for refining engineering assumptions, distinguishing structurally controlled instability from operationally induced overbreak, and progressively reducing uncertainty throughout pit development. The proposed workflow provides a practical framework for improving confidence in bench-scale design optimisation and supporting risk-informed geotechnical decision-making through continuous operational reconciliation and iterative refinement of engineering interpretation.

Contributors

Authors

  1. Felipe Sanz SRK Consulting UK Ltd, United Kingdom ORCID 0009-0003-0254-7325

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References

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