Search Documents

By J Taylor, L Richards, M McKenzie

When a collapse in its services shaft caused rapid gas build up and its premature closure in. 1951, the Blackwater Mine at Wiauta was in full production with significant ore reserves yet to be mined. A total of nearly 23 tonnes of gold was produced from the mine during its 44 year life. It was New ZealandÆs deepest underground mine, producing gold from an extensive sub-vertical mineralised quartz reef that averaged 0.6 m in width. Mining was by stoping between adits and short shafts, latterly with the main mine access through the 840 m deep Prohibition shaft. Macraes Mining Company Ltd are presently investigating the possibility of reopening the mine. This paper outlines a preliminary assessment of the main geotechnical factors for achieving the reopening, using recent exploration and old mine information. The greywacke host rock mass in the vicinity of the quartz reef has been evaluated using both these sources, and the paper discusses how the geological structure, intact and rock mass strengths, the rock mass defects, in situ stresses, and groundwater inflows may effect the reopening and support of the prohibition shaft, the excavation methods and support for a new supplementary shaft, and the likely excavation and support requirements for working adits and stopes in the rejuvenated mine.

Jan 1, 1996

Inpit tailings disposal has been undertaken at a number of mining sites within Australia. This paper presents a brief history of the experience of inpit tailings disposal at the Marymia Gold Operation in Western Australia, including geotechnical aspects of the design. Regular monitoring of the inpit tailings disposal into the K1SE Pit at Marymia has allowed the operators of the mine to assess the performance of the tailings storage against its predicted performance during the design phase. Results of this monitoring indicated that the predicted performance was exceeded and the results have been incorporated into the design of another large inpit tailings disposal, the K1 Pit. Monitoring of tailings disposal to both the K1SE Pit and K1 Pit has allowed the mine operator to make substantial savings from inpit tailings storage when compared with above ground tailings storage facilities. The inpit method of tailings disposal at Marymia has proven to be acceptable from an environmental perspective by reducing the water resource requirements of the project, backfilling pits, which would otherwise collapse with time and eliminating the need for disturbing additional areas of mining leases, which usually accompanies construction of above ground tailings storage facilities.

Jan 1, 1999

By B Y. Luan, Y Tian, W Zhou, X Lu, Q X. Cai

The unmanned driving technology in open pit coalmines is an important technology that relies on innovation to drive the development of the open pit coal mining industry in China’s transformation of growth drivers and industrial structure upgrading. It is an important path to solve the shortage of mine truck drivers in the future mining, an important way to improve the working environment of open pit mining personnel, and an important foundation for achieving flexible production capacity in open pit mining to cooperate with the coordinated development of new energy. The communication rules at intersections are key to ensuring the safety and efficiency of unmanned driving in open pit coalmines. This paper proposes a collaborative traffic strategy between unmanned trucks for the single bucket unmanned truck intermittent process system in open pit coalmines. Based on the gap theory, this paper analyses the conflict characteristics and establishes a coordinated traffic strategy for the common intersection and merging conflicts of unmanned truck trucks in open pit coalmines, A multi-agent system simulation platform was built to evaluate the coordinated traffic efficiency under different initial average gap sizes of vehicles, with intersection traffic density, vehicle speed, and gap changes as key indicators. The results show that under the simulation conditions of this article, when the initial average gap of vehicles reaches three (four) times or more of the safe distance, the coordinated traffic performance of intersection conflicts (merging conflicts) is better, and the traffic capacity of intersections is close to the traffic capacity without conflicts.

Sep 1, 2024

By J Foster

The Lanfranchi Nickel mine is located approximately 48 km south of Kambalda in Western Australia. Mining first commenced in the mid-1970s under the previous owner, Western Mining Corporation Ltd. After two years on care and maintenance, Panoramic Resources (previously known as Sally Malay Mining Ltd) purchased the operation in November 2004. The site currently produces approximately 10?000 tonnes of nickel metal annually from approximately 430?000 tonnes of ore. The Ore is mined from four main orebodies; Deacon, Helmut South, Lanfranchi and Schmitz. The Helmut South orebody is situated approximately 790 m below surface and extends to a resource depth of 940 m. Horizontal thickness of the orebody ranges from 10 m to 45 m in width, with the average being 30 m. Previous mining at the Lanfranchi operations specifically the Helmut orebody, had a history of seismic activity. When Panoramic Resources acquired the operation it was decided that seismicity was going to be an issue and therefore a mining method needed to be selected that could effectively manage this potential risk. The dip of the orebody is quite shallow at 45º, with a 30º plunge to the south . The hanging-wall comprises of very weak ultramafics. Due to these factors the orebody posed several mining challenges. To safely and effectively mine the Helmut South orebody in the Lanfranchi Nickel mine, underhand cut and fill mining was selected as the most appropriate mining method. Paste fill comprising of cemented gold tailings was the backfill of choice. This paper is intended to convey some of the key learnings from the use of a mining method that has not been commonly practiced in Australia.

Mar 21, 2011

Block caving is the lowest cost underground mining method but it has relatively high risks and a high up-front capital and development cost. It has application to large, often lower-grade orebodies where high production rates can provide good returns on the investment. However, it has a range of technical risks that are peculiar to block caving and the usual financial, political and environmental risks that may be exacerbated by the long lead-in times associated with the development of a block cave operation. With initial development costs that may be $100 M to $1000 M when the building of a treatment plant is also required, it is obviously important to minimise and manage the risks. In a greenfield project, commitment to a substantial proportion of the capital expenditure may be required to gain access to the deposit, and the decision to proceed at this stage would be based very largely on interpretations of drill hole data. In established mines the data may be supplemented by geological mapping and past experience, etc. The quality of this data is critical and yet it is frequently degraded through poor techniques and avoidable omissions. The final decision to proceed would be assessed on projected commodity prices, mining capital and operating costs, dilution and run of mine ore grades. The latter will vary over the life of the project and these can be estimated with drawdown or draw control modelling techniques. In this modelling, there are further risks in the assumed modelling parameters or that the modelling technique may not be applicable or appropriate. The paper addresses the most critical technical and operational risk areas and provides some practical precautions that can be taken to reduce these and improve the reliability of the geological and geotechnical models.

Jan 1, 2000

By E Rubio, N Morales

A common practice in the mining industry is to decompose the planning process into different tasks, so the overall process and specific schedules can be constructed easily. Nevertheless, currently there are some adverse effects, such as not capturing the real value of a project by not taking into account the construction of several underground drifts and general infrastructure. Then the common practice is to compute mining sequence and cut-off grade profiles over the life of the mine without constitutively integrating the development schedule as a means to measure the constructability of a given mine design and sequence. Thus, the investigation summarised in this paper shows a novel, integrative way of treating an underground mine sequence and production schedule while considering drift development scheduling. Moreover, it is thought that, because of this original model, the whole underground production scheduling exercise must concentrate on combining the development and the production scheduling to compute a robust and a feasible production schedule.In order to quantify the effect of the conventional way of viewing the planning, the concept of the building information model (BIM) needs to be used, which was postulated by Charles Eastman and has been used extensively since the late 1970s. BIM takes other aspects of a project into account, considering at the same time the spatial relationships, quantities and properties of building components, but especially some kind of model visualisation, which is the advantage to be incorporated. This paper presents the basis for an optimisation model that allows for defining the sequence of the mining development so that the production plan can be achieved. For this, the model considers the space dimensions, time, pattern or strategy, cost or benefit, precedence and resources available. Tests were performed considering a block caving and sublevel open stoping method. Finally these tests showed the main conclusion, that production sequence changes when the building capacity is considered.

Sep 26, 2011

The creation of an accurate and precise enough database requires the collection of many representative samples, subsampling and assaying them without destroying their integrity. The selection and implementation of sampling protocols often lead to severe difficulties, making the unaware practitioner vulnerable to massive exploration, feasibility and operating failures. Therefore, there is no substitute for a good understanding of the Theory of Sampling (TOS). Either because of ignorance, or because of short-term economic reasons, failure to comply with many stringent conditions can be devastating for the validity of a feasibility study, leading to false evaluations, to the abandonment of a viable property, or to the exploitation of one that is not profitable. All these failures have something in common: insufficient duplicate sampling, subsampling and assaying were performed; very important, preliminary heterogeneity tests were never performed; for short-term economic reasons, poor sampling and subsampling protocols were selected, second-class sampling systems and weightometers were installed and poor preventive maintenance and cleaning were implemented;and sampling experts were called only when the project was obviously in trouble. The conclusion is clear: in due time, iterative auditing of sampling practices is an insurance policy against massive financial losses for the company involved. A complete, comprehensive 100 point checklist of sampling Quality Assurance and Quality Control is provided, so critically important details to ensure success are not forgotten.

Mar 1, 2010

By D J. Brake

There are many sources of gas in underground mines including development and production blasting, strata gases, spontaneous combustion, diesel equipment, chemicals used for a wide range of functions, welding activities and fires.It is only in relatively recent times that electronic gas monitors (or detectors) have become both safe and affordable for routine use.In modern mines, gas monitors should be in daily use by the ventilation department as well as blasting re-entry (or clearance) crews, and are often used by drilling crews, shift supervisors, hygienists and mine rescue or fire fighting crews.When first released, electronic gas monitors needed to be sent off-site periodically for calibration at a suitable accredited laboratory. Between calibrations, their accuracy was unknown. More recently, ‘bump testing’ and field calibration has become possible on the mine site, improving both reliability and safety as well as reducing the total number of gas monitors that need to be in use.There has been almost an overwhelming increase in the number and sophistication of gas monitor features in recent years. This paper reports on a case study into the key criteria that ventilation practitioners should be aware of with respect to the specification and selection of the most recent gas monitoring systems, and recommends good practice for site-based operation and calibration.CITATION:Brake, D J, 2015. Specification and selection of hand-held gas monitors (detectors) for underground mines, in Proceedings The Australian Mine Ventilation Conference, pp 143–154 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 31, 2015

By F Hungerford, T Ren

"Gas management has always been a major concern for the ventilation officer of any gassy mine. With an increase of mining depth and gas content, there is a great demand for the development of in-seam drilling sites where boreholes can be drilled for the pre-drainage of gas prior to longwall operation. The ventilation and gas management in the drilling site therefore becomes a critical component of mine safety. In this study, advanced computational fluid dynamics technology was adopted to investigate the aerodynamics of gas emitting from the drilling site and boreholes during normal drilling and, in the case of a sudden gas inrush, from the borehole. In addition, the impact of different ventilation controls on gas removal in the drilling site was investigated. Modelling results indicate that gas accumulation zones could be formed if the ventilation system fails to deliver sufficient airflow to the drill site, especially when a sudden gas inrush from a borehole occurs. The configurations of brattice, layout of ventilation tubes and the gas emission rate all have a significant effect on the gas distribution. Due to variations in site-specific conditions, it would be desirable to conduct modelling studies to assess the effects and efficiencies of a ventilation design for the varying environment on-site before carrying out drilling practice. CITATION: Ren, T, Hungerford, F and Wang, Z, 2015. Computational modelling studies of ventilation management for underground in-seam drilling sites, in Proceedings The Australian Mine Ventilation Conference, pp 239–250 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Aug 31, 2015

By R Long

The founder of social psychology is sometimes identified as Kurt Lewin. In a 1947 article, Kurt Lewin coined the term ‘group dynamics’. He described this notion as the way that groups and individuals act and react to changing circumstances. Lewin theorised that when a group is established it becomes a unified system with unique dynamics that cannot be understood by evaluating members individually. The discipline of social psychology really emerged out of World War II and tackled questions associated with human judgement and decision-making by the Nazis. For a comprehensive look at the development of social psychology look at Abelson, Frey and Gregg (2004).Social psychology is concerned with the way social arrangements affect human judgement and decision-making. What the author has done is apply the knowledge of this new discipline to an understanding of risk, safety and leadership. This paper will explain some of the developments in social psychology, such as the discovery of the bystander effect, Groupthink, bounded rationality, heuristics, risk homeostasis and the Milgram effect.The social psychology of risk tackles the way decisions are made about risk in their social context. Unless organisations understand that decision-making is socially conditioned, they are unlikely to be able to tackle the complexities of culture change or the development of risk maturity.The paper will offer a new understanding of why people do what they do, how risk makes sense and why a ‘dumb down’ approach to safety is dangerous. A model will also be presented that shows the pathway to risk maturity.CITATION:Long, R, 2016. The social psychology of risk, safety and leadership maturity, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 31–42 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By A Murphy

Mining plants and infrastructure, and the decisions made by their designers, can have large impacts on their environmental and social context, commonly referred to as the site or plant footprint. They can also be the source of constructive contributions to sustainable development when designers are enabled via the information, systems and tools to incorporate sustainability in engineering processes. A facility’s footprint and the project’s contribution to sustainability – economic, environmental and social aspects – are now key considerations in regulatory approval processes and are the fundamental drivers of support, or opposition, from the project’s stakeholders.Historically, plant and infrastructure designers have not been well integrated with the environmental and social professionals who are engaged to pursue regulatory approvals. Despite this, many objectives central to technical and process engineering have in fact contributed positively to a facility’s footprint and indeed its contribution to sustainable development. Examples of these objectives include increasing process and energy efficiency, and minimising the quantities of waste requiring disposal. With the framework of sustainability, mining plant and infrastructure designers are indeed at the forefront of incorporating sustainability into resource industry projects and are central to the process of obtaining regulatory approvals and ongoing stakeholder support. The process of incorporation starts with a shared understanding of sustainability and sustainable development, and continues with project processes that facilitate information and knowledge exchange throughout the project life cycle.CITATION:Murphy, A, 2014. Incorporating sustainability into mining plant and infrastructure design, in Proceedings Life-of-Mine 2014 , pp 637–646 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By S Watson, L Martinez

Mine projects are complex opportunities that demand a constant assessment of uncertainty, ie risk and upside potential. This is because the value of a mine project is typically influenced by many underlying economic and physical uncertainties, such as metal/mineral prices, metal/mineral grades, costs, schedules, quantities, and environmental issues, amongst others, which are not known with much certainty at the beginning of the project. But, is uncertainty an enemy or an ally of the mine planner/analyst? To answer this question, this paper first assesses and elaborates upon the general concept of uncertainty. It then looks at the different sources of uncertainty in a mining project, such as the orebody, costs and product price uncertainties, and their effect on the final project value. Next, a general?review?of current mine evaluation techniques highlighting their limitations when dealing with uncertainty is made. Finally, an extended evaluation and risk management framework that addresses the existing uncertainty in the (greenfield/brownfield) mine evaluation process is proposed. One important characteristic of this framework is that it uses and manages uncertainty in order to generate additional value to the project; this is done through operational and managerial flexibility, which allow mine planners to minimise/maximise project risk/upside-potential giving a more realistic estimate of the projectÆs market value - this is shown in practical and simple examples occurring at different stages of a mine project, such as exploration and operation. Final conclusions are provided at the end.CITATION:Martinez, L and Watson, S, 2012. Uncertainty - An important source of (additional) value for mine projects, in Proceedings Project Evaluation 2012 , pp 131-140 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 24, 2012

By H S. Mitri, A Sainoki

Destress blasting techniques have been widely employed in underground mines for the purpose of preconditioning highly stressed rock mass. Appropriate applications of the technique successfully contribute to increasing mine safety (eg mitigating the risks for rock bursts). This paper presents a simulation technique to estimate the extent of damage zones induced by destress blasting. A 3D numerical model with a single blasthole is constructed with FLAC3D code, whereby static analysis is carried out in which horizontal and vertical stresses are applied to the model in order to simulate stress conditions in a deep underground mine. Afterwards, dynamic analysis is performed whilst applying time-varying blast pressure along the blasthole. The blast pressure profile takes into consideration an instantaneous increase and gradual decrease in blast pressure as well as the propagation of detonation along the blasthole. In this paper, constitutive models allowing for shear and tensile strengths of rock mass that are dependent upon strain rate are newly implemented into FLAC3D code with C++ programming language, whereby blast-induced damage is assessed by the extent of tensile and shear failure zones. The results obtained from the dynamic analysis show significant decrease in the extent of yielding zones induced by destress blasting with increasing the magnitude of in situ stress. They indicate that considering in situ stress state is indispensable in order to propose proper blast design for each level in underground mines. Based on these results, the relationship between the extent of the damage zone and depth at which destress blasting is performed is established. Furthermore, stress dissipation induced by destress blasting is examined with static analyses, in which the modulus of elasticity is decreased according to a rock fragmentation factor, a, only for the area where tensile and shear failures takes place during the dynamic analyses. A model parametrical study with respect to a is undertaken. The relationship between the rock fragmentation factor and the stress dissipation in the yielding zones is developed from the parametrical study. The developed relationship can be useful when destress blasting is designed for massive rock masses.CITATION:Sainoki, A and Mitri, H S, 2015. Simulation of damage zones induced by destress blasting, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 245–256 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By J Ta’ala, M Handyside

Mechanical sampling from conveyors has historically been a staple in the iron ore industry when information related to chemistry, sizing and moisture is required. In order to comply with ISO 3082:2009, samples can be taken either on a mass or time basis provided no bias is introduced by periodical variation in quality or quantity. With the introduction of mechanical sample carousels, you also have the opportunity to collect samples on a mass or time basis. In order to optimise automatic sample stations in a changing production environment, BHP Billiton Iron Ore (BHPBIO) has developed a simulation model that enables the various combinations of mass–mass, mass–time, time–time and time–mass to be investigated.The sample station model can utilise actual (variable) feed rates to achieve high resolution and enables the simulation of sample size variation. Cutter speeds and other settings can then be adjusted to better optimise the performance of the sample station with regards to optimal sample size as well as ensuring the sample station is in compliance with ISO 3082. The model can also assist process engineers in adjusting settings to better optimise the sample station and reduce unwanted events such as blockages. The model can be easily modified to conform to various sample station designs. This paper demonstrates the use of the model and the benefits that can be achieved.CITATION:Handyside, M and Ta’ala, J, 2014. Simulating time versus mass basis?sampling, in Proceedings Sampling 2014 , pp 155–164 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 29, 2014

By S L. Martin, M Wimberger

The binary indicator coding of assay and lithological data according to a single criterion or multiple criteria is a powerful technique for representing mineralised shapes through the modelling of probabilities. This can be as simple as using a single indicator to model the probability of occurrence of a condition, usually a grade threshold or a lithology, but it can also be used with a number of categories. Case studies are presented to show the power of this approach, where the geological controls on mineralisation or on the distribution of a rocktype or alteration, often coupled with mineralisation, are unclear. The categorical approach is often used as a de facto grade filter in disseminated or stockwork mineralisation. The ultimate expression of the indicator formalism is in multiple indicator kriging (MIK), where a conditional distribution of probabilities is generated for each estimation panel. This has applications in recoverable resource estimation, as the input for continuous or categorical simulation, where the distribution of sample grades is multimodal, or when there are superimposed mineralisation events with different orientations. However, in some cases, MIK is being used as an excuse for ignoring a quality geological interpretation. Examples from the public domain show the abuse of the categorical and MIK approaches to modelling probabilities, together with a plea for greater consideration of the geology.

Mar 22, 2022

By J M. Galvin

The traditional engineering approach to assessing stability is based on comparing resisting force (capacity) to driving force (demand), or strength to working stress. In underground coal geomechanics, considerable effort has been expended on quantifying the strength of rock structures. However, this has not been matched by advances in determining the load acting on these structures, reflecting a reluctance by some to embrace numerical modelling to assess load magnitudes and distributions. Numerical modelling is a valuable aid as loading environments are a function of both the stiffness of the mine workings and the stiffness of the superincumbent strata and are statically indeterminate in most cases.This paper defines stiffness, which is often confused with elastic modulus. It shows that, effectively, stiffness encapsulates geology, depth of mining, panel width, pillar width and mining height. Therefore, these factors are variables that need to be taken into account when determining stress magnitudes and distributions about mine workings. A range of examples are presented that illustrate the significance of the stiffness of the superincumbent strata on surface subsidence; the magnitude and distribution of pillar and abutment load; and aspects of bord and pillar mining, pillar extraction and longwall mining. These examples provide bases for identifying the limitations of some empirical approaches to mine design, identifying how to compensate for some of these in design processes; and emphasising the need to make greater use of numerical modelling in understanding and quantifying loading environments in underground coal mining.CITATION:Galvin, J M, 2014. The significance of superincumbent strata stiffness and its impacts on coalmine design, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 3–16 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014

By M F. Lee

Although the Mt Charlotte gold resource was discovered in 1893, it was only in 1954 that geologists correctly interpreted drill data and defined a large low-grade orebody. The mine has been a large, low-cost and profitable producer since 1962 when bulk mining commenced using cut and fill. From 1968 a combination of long hole open stoping with delayed mass blasting was used. This proved to be an excellent mining method for the large, separate subvertical orebodies. The structured but otherwise good quality rock allowed very large stopes to stand unsupported. Exceptionally large equipment, for its time, was used to efficiently mine, muck and move the ore at low-cost. The mine only just survived severe cost pressures in 1974-76, due to very low gold prices. Better gold prices in 1979 and a need to access deeper ore meant a bold commitment to sink the Cassidy Shaft and refurbish the mine to sustain future profitability. In 1997 the Sam Pearce Decline connected to the underground workings, making it profitable to mine upper level remnant ore. Mining-induced seismicity has been a feature of mining at Mt Charlotte. The main cause has been shearing on structures. A mine-wide seismic system was installed in 1994. Large seismic events have occasionally made management question whether a safe working environment can be maintained. Thorough investigations led to an understanding of the problem and development of procedures to minimise seismicity.

Jan 1, 2000

For effective backfilling, a system with the 13 features covered under the section: effective backfill systems, is required. Effective backfilling cannot be done with systems that are badly designed, outdated or overextended. But in cases where the requirements for effective backfilling are overlooked, the shortcomings of such systems may wrongly come to be regarded as limitations to the capabilities of backfilling per se. Mining is currently done to depths of 3500 m, and is to go deeper since the gold-bearing reef extends down to 4000 m and 5000 m below surface. Effective backfilling systems will be required at such depths, and with suitable design this can be achieved. Mining the narrow tabular orebody of a typical South African gold mine is described at the start of this paper, then cycloned backfilling is discussed in general, and its effectiveness (most of the fill placed in South Africa is cycloned backfill or ædeslimed tailingsÆ).

Jan 1, 1998

By J A. Rowland

When executing a ventilation change the mine ventilation circuit is in a state of flux throughout the entire change period with discrete mine areas both under ventilated and/or over ventilated during the change process. Whilst routine risk reduction strategies such as removing electrical power and people from the mine are commonly deployed it is wise to complete the change in the shortest practical time frame. This not only minimises the chance of unacceptable concentrations of contaminants accumulating around the mine but reduces the impedance on production activities which are routinely suspended during these change periods. This paper firstly highlights the importance of the maintenance of an accurate ventilation model and discusses issues which should be considered to assist to maintain in it a suitable state of health. Further it provides some tips on how to monitor that your model is in an acceptable state of tune so that it can be confidently deployed in the change process. Finally, it details the sequential process how a finely tuned and accurate ventilation model can be utilised to carry out major ventilation changes according to appliance pressure adjustments only and without the need to constantly measure and check resultant branch flows throughout the whole change process. Also discussed are some simple practical tips which will help ensure that the ventilation change process will go according to the devised plan on the day and in the most appropriate order including checking the efficiency and accuracy of the change, after it is completed.

Oct 12, 2022

By M Sandy, A Vakili, J Albrecht

Although rock strength anisotropy is a well-known phenomenon in rock mechanics, its impact on geotechnical design is often ignored. No widely accepted guideline currently exists for its characterisation. Anisotropy can significantly control the failure mechanism and progression of damage into the rock mass, particularly in high-stress conditions. As such, it can play a key role in the stability of underground excavations and subsequent geotechnical design.This paper introduces the concept of anisotropy at both intact and rock mass scales. It then presents guidelines for measuring anisotropy and assigning rock mass strength properties. An improved unified constitutive model (IUCM), which can account for more complex failure mechanisms, is then briefly described. This IUCM is used to better understand the typical responses of anisotropic rocks to underground mining and to develop an improved damage classification scheme for these conditions.The application of conventional design methods in anisotropic conditions is shown to lead to significant errors. Two case histories are then presented, illustrating how the proposed methodology can improve the reliability and accuracy of the geotechnical analysis when compared with conventional design methods.CITATION:Vakili, A, Albrecht, J and Sandy, M, 2014. Rock strength anisotropy and its importance in underground geotechnical design, in Proceedings AusRock 2014: Third Australasian Ground Control in Mining Conference , pp 167–180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 5, 2014