A model of the sequence of decisions required for mine development and production has been formulated and is operated as a computer-based game. The Mine Manager is an operations research game in which the user assumes the role of mine management in the exploitation of a mineral deposit. Potential applications of the game lie in experimentation, policy formulation and education in mine economics. The Mine Manager is described using the terminology of games. / The selection of parameters and of the level of detail in the model reflects a compromise between realism and simplicity. At the development stage, the selection of project specifications concerns the mining method and capacity installation. Decisions on cut-off grade and/or cut-off value, capacity utilization, the sequence of mining, stockpiling and expansion are made during the mine life. Decision making takes place within a framework provided by an abstraction of the operating environment of a mine, and must comply with a set of rules. These rules ensure that only feasible decisions are made. Within this constraint, the model offers a high degree of flexibility in setting the values of the decision variables. / The Mine Manager combines elements of geology, mining, management and gaming. Conditional simulation is used to generate grades of copper, zinc and gold in a massive sulphide deposit. Mining operations in both underground and open-pit mines are modelled, and hypothetical capital and operating cost functions are developed for the mine and mill. A pricing model generates new price series for each run of the game. / The Mine Manager is operated interactively on a microcomputer through the use of modular software. The user interface and a sample run of the game are described, and the information displays created by the game are presented.

This thesis reviews, analyses and classifies extraction methods and sequences used in steep, tabular orebodies in Ontario hardrock mines and how new bulk mining techniques have affected them. / The thesis examines, as a case study, the complexities of sequencing the extraction of the Hemlo orebody through three adjacent mines and details the planning and monitoring of extracting one section of the David Bell orebody. It examines the use of numerical modelling as a tool in extraction sequence planning and demonstrates how, in conjunction with an instrumentation program, the results assist successful completion of the plan. / The thesis concludes that bulk mining sequences have increased resource extraction and productivity, lowered costs and improved ground control aspects of extraction planning; but have compromised grade control. This aspect should be improved to maximize the economic benefits. In addition, as automated or continuous mining methods are developed, their benefits should be analyzed in the context of overall sequence planning objectives.

This thesis addresses those mine design considerations applied to mining with backfill at Denison Mines Ltd., Elliot Lake, Ontario, and reviews the specific circumstances of pillar recovery during 1985 to 1988. The rock mechanics elements of the project are presented with a case history of pillar recovery in a specific stopping district (cost center). / The use of hydraulically placed cemented tailings to recover additional ore reserves from rib pillars in a room and pillar mine required a design rationale beyond the traditional empirical approach. / The work undertaken to achieve this improved design includes both the study of the physical properties of the backfill, and its overall support characteristics. Design techniques involving analytical and numerical methods were coupled with ground behaviour data from daily monitoring and rock instrumentation. / The backfill cost center used as a case study is back analyzed with reference to a new proposed pillar strength classification system. Improvements in ground stability are assessed and comparisons with rock burst alleviation studies are made. The geomechanical parameters involving pillar design are discussed at length in the context of rock mechanics theory. This thesis attempts to demonstrate the manner in which an integrated design rationale may be employed in a room and pillar mining environment.

This thesis presents a research program designed to evaluate the performance of the gold gravity circuit at Les Mines Camchib Inc. / A detailed sampling program was conducted on the grinding and gravity circuits. Samples were screened and each size class was processed on a Mozley Laboratory Separator to determine free gold content. The performance of pinched sluices, Knelson concentrators, and a riffleless table is characterized on the basis of particle size, shape and liberation of gold. The amount of total gold and free gold in each size class of grinding circuit streams was also determined. / The pinched sluices recover from 8 to 17% gold in 4.8 to 7.3% of the mass. The double sluice recovers slightly more gold at a higher yield than the single sluice. In addition, the double sluice performed better at a higher feed density. / The 76 cm (30") Knelson recovers 62 to 71% of the feed gold, at very high upgrading ratios (326 to 480). Free gold recovery is high, generally above 90% for all size classes. Gold recovery decreases when wash water pressure is lowered from 100 to 40 kPa; a 90 minute cycle time does not cause concentrate overload, i.e. decreased gold recovery. / The 19 cm (7.5") Knelson used in the gold room yielded 90% recovery. Reprocessing the tails in the same unit give only a marginal gold recovery, suggesting that a single pass is adequate. Fine gold losses on the riffleless table are significant, especially in $-$38 $ mu$m (400 mesh).

This thesis examines rock mass characteristics of the Bousquet 2 mine, and reviews ground reinforcement practices applied to tunnel and stope hanging-wall support. The effectiveness and suitability of the installed support elements is examined through numerical modelling techniques and instrumentation. / The second part of the thesis examines mechanisms influencing stope hanging-wall stability. Through a case study incorporating hanging-wall instrumentation, numerical modelling, and laser survey of the mined stope profiles, the extent of hanging-wall over-break in both primary and secondary stopes is studied.

For centuries human society has relied on coal as a principal source of fuel for heat and power. Extraction of this valuable fuel has always been influenced by control over hazards such as water inflows and potentially explosive dust and methane gas. A major focus of the research has been on methane including: methane properties of seams, insitu and laboratory testing; methane emissions; investigation of operational issues (e. g. Phalen 7 East); and refinement of prediction models. / This thesis gives an overview of methane and ventilation research covering the following aspects: Defining coal seam characteristics: specific emissions---the relationship between methane content, coal 'rank' and depth; the geothermal gradient; insitu gas pressure; and associated hydrocarbon content of mine air samples analyzed. Defining the performance of Sewergate ventilation, particularly on Phalen 7 East. Sewergate ventilation is a marriage between a typical 'U' and a bleeder ventilation system. Underground measurements including a novel use of 'tubebundles', have provided a clearer understanding of factors affecting Sewergate performance. (Abstract shortened by UMI.)

This work presents an experimental database encompassing known and suspected factors causing in-the-hole deviation when drilling long production holes at Canadian underground mines. / Using this experimental database and previous studies on the subject, an idealized model of minimal detail but complete structure is proposed using the principles of beam bending, the constraining effect of the drill hole on the drill string and simple relationships for bit rock interaction. / Next, the proposed model is programmed digitally to produce a longhole drill deviation simulator, which is first checked for self consistency and stability and then verified against the experimental field results obtained earlier. / The model's prediction agrees, within the known working limits of the simulator, with the trends observed in the field as regards to the effects of pipe weight, hole inclination, hole length and feed force. In addition, the model's prediction shows the crucial importance of geology on the observed deviation process and the three-dimensional nature of drillhole deviation. Because of its scientific basis, the model can be further developed to include additional factors when required.

Backfill design is a multi-level, data/information/expertise intensive procedure involving various professional fields. During the life cycle of mining design and operation, a series of decisions are made based on the knowledge and personal experience. The success of mining design depends largely on knowledge available, and how knowledge is managed and processed. This thesis presents a conceptual backfill design rationale in a systematic approach in terms of basic information needs and data flow. Based on this representation, an integrated decision support system for backfill design is introduced. The underlying system is based on the integration of traditional databases, expert systems, hypermedia, and logical programming concepts consisting of the following components: (1) user interface, which creates the model of tasks and the application environment; (2) hypermedia-based reference manual, which supports non-linear access to backfill design reference manual of various formats; (3) expert systems which solve certain tasks based on heuristic rules; and finally, (4) knowledge base management system which provides an efficient approach to manage and manipulate massive data of previous backfill operations. The integration of these components is achieved through a blackboard architecture. The early test of the prototype system shows that the basic objectives have been achieved to provide fast information access and certain decision makings.

The access tunnels for the Donkin-Morien Mine in Cape Breton, Nova Scotia comprise two parallel tunnels driven through a sedimentary sequence of sandstone, siltstone and mudstone to intersect the Harbour Coal Seam under the Atlantic Ocean, approximately 3.5 km offshore. / During the period May 1983 to December 1984, a geotechnical research programme was carried out in the Donkin-Morien tunnels by Golder Associates Ltd. The research programme included the monitoring of the performance of the TBM and drill and blast drivages, and the study of the thrusting characteristics and rock-interaction of the TBM excavation. The main emphasis of the research programme was on the collection of field data, which was to be made available in the form of a comprehensive report. The information gained from the programme was also used during the tunnel drivages to monitor the performance of the installed support and enable changes in the support and advance methods. / Throughout the research programme the author was resident on site at the Donkin-Morien Mine and was responsible for all aspects of the research project.

A significant amount of work has been directed toward the improvement of mine backfill during the past decades. Paste backfill was recently introduced as a superior support system for underground hard rock mining operations. The aim of this study is to examine the applicability of paste backfill to full scale underground operations. / The Tailspinner system was developed to produce paste backfill. This system dewaters the full stream tailing material from approximately 55% to 24% water content. These densified tailings are mixed with cement prior to placement in a stope. / The utilization of paste backfill possesses several economical and mechanical advantages. Paste backfill however, contains a high proportion of ultra fine solids, which results in a material of very low permeability. Hence, the question of liquefaction susceptibility of this material becomes important. / This investigation is directed primarily towards the behavior of paste backfill when subjected to static and dynamic loading conditions. The main objective of this study was to evaluate the liquefaction resistance of paste backfill. However in order to accomplish this goal, studies also have to be made into the static characteristics. The behavior of both reconstituted and undisturbed samples were investigated. / A comprehensive testing program on paste backfill samples was carried out. The static testing program was conducted to define the strength and deformation characteristics of paste backfill. The influence of cement and water content on static properties of paste backfill were investigated. / The liquefaction resistance of paste backfill was evaluated based on several mechanisms. The results of a comprehensive study on the liquefaction potential of paste backfill are presented. The effect of variation in void ratio, confining pressure and cement content on the liquefaction resistance of backfill were investigated. / The in situ tests were conducted on a paste backfilled stope at Dome Mines. A unique in situ testing program using a piezometer friction cone was carried out. This enabled the determination of the geotechnical characteristics and the evaluation of the liquefaction potential of paste backfill. The dynamic properties of the paste backfill were also investigated through a series of blasts adjacent to the backfilled stope. The resultant energy transfer and peak particle velocity transmitted through the rock and paste backfill was monitored with a series of accelerometers. / The liquefaction analyses show that liquefaction resistance increases with increasing cement content and decreasing void ratio. Various curves were developed to present the influence of the above parameters for paste backfill application. The laboratory and in situ results obtained in this study should improve the understanding of backfill properties for design and operational purposes.