Aims and Overview

The ideas outlined in literature concerning rock slope failure mechanisms and the appropriateness of different pit slope design approaches are diverse.

To overcome the uncertainties generated by this diversity, the project has prepared and published authoritative new generation pit slope design guidelines detailing accepted practice for today’s practitioners.   The aims and objectives of the publication, titled Guidelines for Open Pit Slope Design, are to link innovative mining geomechanics research together with accepted practice highlighting:

The project’s fundamental objective is to provide the slope design practitioner with sufficient armoury to ensure that if the slopes do fail there will be:

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Chapter Outlines

A Guidelines for Open Pit Slope Design book contains 14 chapters that follow the life of mine sequence from concept through to closure.

In order to help the practitioner deal with short comings in the investigation and design process, each chapter deliberately focuses on leading issues such as what data is required, how it should be processed and which analysis should be used.
The chapter contents are as follows:


Chapter 1: Fundamentals of Slope Design

Outlining the fundamentals associated with achieving a balanced design in terms of the expectations of the various stakeholders in the mining operation (owners, management, workforce and regulators), including:

• the aims of pit slope design;
• the framework, both corporate and regulatory, that control slope designs; and
• the geotechnical requirements at each stage of project development, from the initial conceptual study through pre feasibility and feasibility to detailed design, operation, and mine closure.

Chapter 2: Field Data Collection

Outlining the availability and application of the mainstream technologies that are used to provide a functional engineering classification of the rock mass for slope design purposes.

Chapter 3: Geological Model

Linking the regional geology and the events that lead to the formation of the orebody to a mine-scale description of the nature (rock type, degree of weathering and alteration) and distribution of each geological unit on site.

Chapter 4: Structural Model

Describing the orientation, distribution and nature of; through-going faults at the regional, overall pit slope and inter-ramp scales, and lesser faults and joints (fabric) at the inter-ramp and bench scale.

Chapter 5: Rock Mass Model

Describing the engineering properties of the rock mass and its constituents, including:

• the nature of the standard index and mechanical property tests that are used in rock slope engineering;
• the properties of the mechanical defects in the rock mass, especially shear strength and the effect of surface roughness;
• rock mass classification systems; and
• current and newly developed means of assessing the strength of the rock mass.

Chapter 6: Hydrogeological Model

Describing how the presence of groundwater and the resulting pore water pressure may affect open pit design and performance, including:

• discussion of groundwater hydrogeology and its implications for rock slope engineering in the mining industry;
• a practical explanation of hydrogeology, including the concepts of fracture groundwater flow, how groundwater relates to pore pressures, and the relationship between total and effective stress;
• a distinction between general mine dewatering and slope depressurisation; and
• how a conceptual hydrogeological model is developed, including recharge to fractures, phreatic and piezometric surfaces, vertical and horizontal hydraulic gradients, discharge of water to the slope, the resulting pore pressure distribution in fractured rock.

Chapter 7: Geotechnical Model

Data compilation and assessment, focussing on how the data presented in Chapters 3, 4, 5 and 6 is processed and made ready for use in the design analyses.  The aim of the chapter is to both highlight and provide guidance on those slope design issues for which clarification is frequently being sought.

Chapter 8: Data Uncertainty

Addressing the question of how to assess the reliability of information derived from data that represents only a small portion of a large parent group, and establishing a geotechnical reporting system that reports the uncertainties that are present in the geotechnical data to mine operators, corporate mine management, and the investment community.

Chapter 9: Acceptance Criteria

Outlining the current deterministic and probabilistic acceptance criteria used by management and the potential application of newly developed risk and consequence approaches to supplement the methods now being used.

Chapter 10: Slope Design Methods

Highlighting current and newly developed methods that may be used to predict, back-analyse, and formalise the slope design, optimise the bench, inter-ramp and overall slopes, and estimate the reliability of the final pit walls.

Chapter 11: Design Implementation

Focussing on the operational requirements of mine planning, controlled blasting, slope protection measures, and artificial support.

Chapter 12: Performance Assessment and Monitoring

Outlining measures to be adopted for evaluating the performance of the as constructed walls of the pit, slope monitoring and a ground management plan.

Chapter 13: Risk Management

Outlining how general risk management concepts and processes can be applied to the geotechnical risks associated with each stage of the open pit slope design process.

Chapter 14: Open Pit Closure

Covering the processes and issues to be addressed, statutory requirements, and NGO pitfalls in the mine closure process.
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Public Release
The "Guidelines for Open Pit Slope Design" book is available for sale in Australia, New Zealand and South Africa through CSIRO Publishing. Customers can order by contacting the CSIRO Publishing customer service team or via its e-shop:

Guidelines for Open Pit Slope Design: http://www.publish.csiro.au/pid/6108.htm

CSIRO Publishing customer service:
Tel: +61 3 9662 7666
Local Call: 1300 788 000 (for the cost of a local call within Australia)
Fax +61 3 9662 7555
email: publishing.sales@csiro.au

Customers in all other parts of the world can purchase the book from CRC Press: http://www.crcpress.com/product/isbn/9780415874410

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