Excavation Design and Optimisation - 2025 entry

Effective planning and design of a mining operation is crucial for economic success. This module commences with a review of mine planning requirements and appropriate input data required for design of mining operations. The module will provide an overview of mine planning practice and mine method selection. The module will provide an understanding of mine cut-off grade determination and present industrial mine design techniques and the latest developments in project optimisation. The module will provide knowledge relating to use and application of mine design software. This will include evaluation of stress redistribution, factors influencing the stability of excavations, cut-off grades, optimization algorithms and development of appropriate mine layouts. The module will also look at the mine scheduling process, the requirements for mine studies and reporting codes.

The module provides specialist analysis and design skills associated with mining. The module provides problem-solving, data-handling and evaluation skills. The module also provides an opportunity for students to develop an awareness of risk assessment applied to underground excavation design.

This module gives you specialist analysis and computer-based design skills associated with mining design and scheduling. We will use computer-based tutorials and practical design exercises to emphasise and consolidate key aspects for mine design and scheduling.

Where appropriate, we will use case history information to emphasise important aspects associated with mine optimisation and its influence on design, the variability of geotechnical data and its influence on design.

On successful completion of this module, you should be familiar with these Knowledge and Skills as specified in the Mine Management Apprenticeship Standard (ST1309):

On successful completion of this module you should be able to:

Module Specific Skills and Knowledge

Discipline Specific Skills and Knowledge

Personal and Key Transferable / Employment Skills and Knowledge

The module commences with a review of critical input parameters for design of underground excavations, emphasising the differences between discontinuity-controlled behaviour and rock mass material-controlled instability.

Excavation results in a redistribution of the in-situ stress field, induced displacements within the rock mass in response to excavation and perturbation of the groundwater.

Data visualisation is a key part of the module, using design-based software for enhanced learning and awareness of both stress-controlled and discontinuity-related failure of underground excavation.

The module covers factors influencing underground excavation design. Key subject areas studied include: - Design methodology (including empirical, analytical, and observational design); - Use and application of rock mass classification for estimation of stabilization requirements.

• Overview of underground mining methods and excavation dimensioning; empirical hangingwall design, including use Laubscher MRMR and Stability Graph Method;
• Stereographic analysis of roof and sidewall instability;
• underground wedge analysis (UnWedge) - Stabilisation techniques/methods, including reinforcement and support, and a review of underground excavation monitoring and instrumentation;
• -Kirsch equations, shape factors, non-circular stress redistribution, effects of discontinuities on excavation stability;

Design of excavations in sedimentary rock;

• Rock mass-support interaction, excavation stabilization techniques and their interaction with ground deformation;
• Pillar design, including estimation of pillar stress and pillar strength;
•  - Large cavern design. The module also includes a review and use of commercially available software for design purposes, and an awareness of deterministic versus probabilistic design and risk.
• Identification and analysis of planar, wedge, direct and flexural toppling, circular, non-circular failure modes, rock-fall analysis to slopes. Slope stabilization techniques/methods and a review of slope monitoring and instrumentation.

Introduction Review of present mine planning and design practices. The requirements for mine planning from scoping to feasibility level study, reserve and reserve reporting.

A review of operating mines planning requirements; short term, medium term and long-term planning. Economic and how they interaction with geotechnical design parameters. Review  geotechnical and economic inputs to mine design.

Review of current Mine Design practice and the use of mine design software, its capabilities, and limitations.

Optimisation Techniques Review mine optimisation techniques currently available for optimisation mine designs such as pseudo flow algorithm.

Cut-off Grade The role of cut-off grade, cut-off grade optimisation and variable cut-off grade where mining, processing or market constraints are present.

The module also includes a review and use of commercially available software for design purposes and an awareness of deterministic versus probabilistic design and risk analysis applied to design.

All passed components of the module will be rolled forward and will not be reassessed in the event of module failure.

Web based and Electronic Resources:

• Hoek’s Corner – https://www.rocscience.com/learning/hoeks-corner

Other Resources:

      Mine Planning

• Hartman H.H., Mutmansky, J.M. Introductory Mining Engineering Wiley 2002
• McPherson M.J Subsurface Ventilation and Environmental Engineering Chapman and Hall 1992
• Hustrulid WA Underground Mining Methods Handbook SME 1982
• Lane KA The Economic Definition of Ore: Cut-off Grades in Theory and Practice 1988
• SME SME Mining Engineering Handbook 3rd 2011
• SME SME Underground Mining Methods Handbook 1982
• Gertsch R E and Bullock R L Techniques in Undergoud Mining 1998

       Underground Rock Mechanicsd

• Brady, B. and Brown, E.T. Rock Mechanics for Underground Mining Chapman & Hall 2004
• Hudson J.A. and Harrison J.P. Engineering Rock Mechanics, An Introduction to the Principles Permagon 2005
• Harrison, J.P. and Hudson J.A Engineering Rock Mechanics Part II: Illustrative worked examples Elsevier 2000
• Hoek, E., Kaiser, P.K. and Bawden W.F. Design of Support for Underground Hard Rock Mines A.A.Balkema 1995
• Hoek, E. and Brown, E.T. Underground Excavations in Rock

      Rock Slope

• Martin, D. & Stacey, P. (2018). Guidelines for Open Pit Slope Design in Weak Rocks, CRC Press, Taylor and Francis.
• Read, J. & Stacey, P. (2009). Guidelines for Open Pit Slope Design, CRC Press, Taylor and Francis.
• Wyllie, D.C. (2018). Rock Slope Engineering (5th Edition), CRC Press

      Blasting

• Atlas Powder Company Explosives and Rock Blasting Field Technical Operations, Atlas Powder Company 1987

Reading list for this module: