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By Y Wei, P Soole

This paper gives a brief description of VirtuoBlast technology ù a new, automated and highly interactive stereo vision technology which has been developed in CSIRO Exploration and Mining. VirtuoBlast technology is an integration of three advanced technologies - close-range digital terrestrial photogrammetry, oblique stereo imaging or high-speed stereo imaging, and temporal-spatial image matching technique. VirtuoBlast has been developed for the automated 3D measurement of blasting through rapid collection, processing, analysis and visualisation of 3D data related to blasting. A major field trial has been undertaken in August 1998 at the KCGM super pit. The field trial involved three applications of the technology, namely, pre-blast 3D surface mapping; post-blast 3D performance measurement; and temporal-spatial modelling of dynamic blasting process. This paper presents some results from this trial with emphasis on the application of VirtuoBlast technology to pre-blast 3D surface mapping and post-blast 3D performance measurement. Application to the temporal-spatial 3D modelling of dynamic blasting process will be presented in a separate paper. Pre- and post-blast surface models derived using both VirtuoBlast technology and conventional field survey method are presented. The differences in results using the two mapping methods clearly show that the digital photogrammetric technique has many advantages over conventional survey methods. Results of pre- and post-blast from the field trial have demonstrated the potential of VirtuoBlast technology to efficiently perform pre-blast 3D surface mapping and post-blast 3D performance measurement of production blasts. Demonstrated applications of VirtuoBlast technology to automated 3D measurement of blasting are showing an exciting future in advancing blasting science and modern blast design. The basic technologies are in place, however, continued improvements to the functionality, robustness and outputs are needed. The challenge is to build on the current state-of-the-art, by developing techniques and hardware which can be easily transferred to and implemented by the mining community. Current and future research and development will see improvements in imaging systems, automatic image processing and 3D data analysis.

Jan 1, 1999

By Manuel Gomez, V. F. Parry, John B. Goodman

"INTRODUCTION The need for an accurate and precise analytical method for determining moisture in coals of high water content has been recognized by the coal industry as well as the fuel technologist. Interest in this particular phase of coal technology extends back to the early work of German investigators on the brown coals of Central Europe. Studies by these workers led to the establishment of a direct immiscible liquid-distillation method 4/ as the accepted moisture determining technique in European laboratories. Direct moisture determining methods, those methods that utilize various techniques to drive off the water from a given sample of coal and either collect the water in a calibrated receiver or selectively trap the water driven off in a suitable absorber, have found little favor in the United States. They have been treated merely as research tools.5/ The problem of moisture determination in low-rank coals of the United States has not been given much consideration because such coals contribute only about 2 percent of the total United States production. With renewed activity in low-temperature carbonization and with the growth of interest in coal and coal-tar hydrogenation, the American coals of lover rank containing 20 to 40 percent bed moisture will be subjected to extensive investigation. If the low-rank coals of the United States are to be accurately appraised, the need for qualitative and quantitative analytical proceeded becomes more pronounced. These coals, especially the lignites of Texas and North Dakota, are highly susceptible to oxidation, a process that proceeds to a greater or less extort when low-rank, high-moisture coals are treated by oven-drying methods. The extent of this atmospheric oxidation has been described and evaluated by numerous workers. 7/In many respects, the problem of moisture determination in low-rank coals, those found in the United States and the high-moisture coals of Central Europe, is similar. Conversely, the problem of moisture determination assumes a different aspect when the coals of the eastern and the middle-west sections of the United States are considered. Present methods, the loss in weight gravimetic-type procedures, serve adequately to test these low-moisture coals. The determination of moisture in coals containing 20 to 40 percent water should be approached from a direct method rather than from an indirect gravimetic-type procedure because of the oxidative tendencies of these coals and the demonstratrated inability of a loss-in-weight technique to remove all the water in a given sample of coal."

May 1, 1953

By AIME AIME

ALL technical men who are planning to visit the Century of Progress Exposition in Chicago this summer-and all reports indicate that it will be worth visiting-should try to be there during Engineers' Week, beginning June 26. At that time most of the national engineering societies of the country will hold important meetings in that city. Engineers will thus have an opportunity not only to see the Fair at a time when special programs have been arranged for their benefit, but will have the opportunity to meet their professional brothers and to attend technical sessions of direct interest to them. The A.I.M.E. headquarters will be at the Stevens Hotel, and it will be to the interest of every Institute member who expects to attend the Fair at that time to secure his accommodations as promptly as possible. A request to the Chairman of the Chicago Section, A.I.M.E., or to the Secretary's office in New York, will bring a copy of the program as soon as it is available, together with any in- formation desired about hotel accommodations or other matters. The Chairman of the Chicago Section is J. R. Van Pelt, and his address is Museum of Science and Industry, 1525 East 53rd St., Chicago.

Jan 1, 1933

By W Farnworth

The Huntly West Mine has undergone significant changes in the last two years, which will affect the remainder of the mine's life. The paper describes the evolvement of plans and an overview of the technical considerations made in planning for and implementing the first New Zealand longwall operation. The technical investigations involve the longwall equipment, exploration, ventilation and strata control. The focus on these areas was to ensure that unacceptable project risks were addressed. Implementation of longwall mining at West Mine is planned in three phases, Development, Panel One extraction trial, and Full Longwall operation.   At present the development phase is complete, longwall installation is in progress and production start-up is planned for the end of August, 1991.

Jan 1, 1991

By W. A. Ahrens, J. H. McNamara, J. G. Franek

"An economical, pollution-free process has been developed for the hydrometallurgical extraction of copper from sulphide ores. The extracted copper, in the form of cuprous chloride (CuC/), is converted by reduction to copper metal. The metal is melted and fire -refined into wire bars which meet the standards of electrolytic tough pitch (ETP) copper wirebars. IntroductionThe successful development of the Cyprus Copper Process has been an evolutionary series of events covering a time span of some nine years. The original process, based on an electrolytic membrane cell principle , was abandoned in 1975 because of technical, economic and pollution problems. During the past four years, the pilot plant has been reconstructed based on a new flowsheet and operated successfully in several campaigns, some for as long as four months. The pilot-plant hydro section operates at a 225-lblhr copper rate. In October 1977, a feasibility study was completed by Jacobs Engineering, Pasadena, California. The study showed favourable economic and technical feasibility. Jacob's studies in 1978-79 revealed favourable comparative economics with other known pyrohydro processes and favourable economies of scale.The Cyprus Copper Process converts copper concentrates of varying composition into copper metal, which has been proven to be equivalent in every way to electrolytic tough pitch copper, suitable for electrical applications. This is accomplished at capital and operating costs which are estimated to be lower than those associated with any other known currently applicable technology. Also, the total energy requirement is equal to or less than any other known process and the process is essentially pollution free."

Jan 1, 1980

By Ernest A. Curth

The Bureau of Mines studied pressure changes in coal pillars by using encapsulated hydraulic pressure cells to measure relative changes in stress developed during mining. The data indicate that (1) abutment stresses were detected when the pillar line is within 42 to 100 feet, (2) vertical pressure increases as coal is mined in the pillars, (3) at first pressure is higher at the edge of the pillar than in the core, but as mining progresses, the higher pressure is measured in the core of the stump, and (4) in the two instances where lateral pressures were measured, they remained lower than the vertical pressures during pillar extraction. The data also indicate that the mean vertical pressure increase, 6P, in a pillar is roughly related to the percent of pillar extracted, A, by the empirical parabolic equation

Jan 1, 1967

By Martin Langenderfer, Catherine Johnson, Alexander Douglas

Mine haul roads degrade rapidly due to extreme loads on suboptimal construction materials. Unmanned aerial vehicles (UAV) are suited to quantify large-area road-network conditions, such as surface roughness, defects and grade to optimize remediation of poor conditions and reduce overall costs. Mine haul roads present unique challenges, such as material type and edge characteristics, to automatic road detection that often fails, requiring manual road input. This research work proposes a new method using the road center determined by the principal curve of a haul truck’s path. Analysis grids were created from this center line. A dense point cloud from UAV photogrammetry was generated and multiple linear regression analysis was conducted on each individual grid. The root-mean-square error in each grid indicates the surface roughness, and the change of slope between grids indicates the road grade inconsistencies. This method was applied to 26 road sections, and the results were validated by images taken from the truck operator’s vantage point. Critical defects were identified including excessive pothole formation, corrugation, depressions retaining water, and narrowing of travel lane. The results demonstrate this is a valid method of road identification and quantification of road defects at a mine site.

Apr 1, 2024

By Donna L. Anderson

This U.S. Bureau of Mines report describes a system to determine the position and heading of a continuous mining machine during the maneuvers required at the face area of a mine. The system consists of commercially available angular position sensors and a computer interface developed and tested at the Bureau. The sensors employed are laser-based scanning devices that report the angular location of retroreflective targets within their 90° field-of-view. The targets are mounted on the continuous mining machine; the laser scanners are mounted on an external reference structure. The computer interface consists of a single-board computer-controller programmed to gather and process the angular position information, and to calculate the machine's position and heading relative to the reference structure. A sensor fusion algorithm will be incorporated into the computer interface programming to increase the accuracy and reliability of the system.

Jan 1, 1989

By W. W. Adams

Lower accident rates were the outstanding feature. of the second annual sand and gravel safety competition conducted in 1930 by the United States Bureau of Mines in cooperation with the National Sand and Gravel Association. Both the frequency and, severity rates for accidents were greatly reduced as compared with those shown by the first year's contest, that for 1929. Three times as many plants were enrolled, and the number of man-hours of work represented wad more than doubled. Seventy-six sand-and-gravel plants, situated in 20 States, participated in the competition, as compared with 26 plants, located in 13 States, in the year before. The number of man-hours of employment, which indicated the amount of exposure to occupational hazards, was 4,915,592 an increase of more than 100 per cent over, the previous year's total of 2.259,572 hours. The frequents of accidents declined from 74.4 per million hours for all plants enrolled in the first year's contest to 42.7 per million man-hours for all plants enrolled in 1930. The accident-severity rate was reduced from 9.7 days of disability per thousand man-hours of exposure in 1929 to 5.9 days of disability per thousand man-hours of exposure in 1930.

Jan 1, 1931

By T. G. Joseph

"The Oil sands-Equipment Interactions Program (OsEIP) is a collaborative research venture between Syncrude Canada Ltd., James Progithin International Ltd. (JPi), the University of Alberta, P&H MinePro, and Caterpillar Inc. The objective is to better understand the behaviour of oil sands as it interacts with mining equipment, in particular, large trucks and shovels. With a move to ever larger equipment, mining oil sands of highly variable bitumen content, ground stability comes into question. This paper outlines this aspect of OsEIP and provides some insight into how some of the findings enable an improved understanding of oil sands behaviour that may impact large equipment design, operational and maintenance strategies. IntroductionThe mechanical behaviour of oil sands in the underfoot and in the face yields some of the harshest stability and digging conditions of any mining environment. High maintenance costs from truck and shovel fatigue failures predominate as a result of ground stability issues. Wear rates of shovel and dozer ground engaging tools (GET), rollers, roller paths and crusher screens result in costly and frequent replacement, or even more frequent and costly sacrificial wear zone building. From the shovel face to the crushers and screens, dry oil sands mechanics affects the degree of fragmentation and, ultimately, bitumen production.An increased knowledge of the behaviour of oil sands with respect to stability, fragmentation and abrasion, etc. would enhance the long-term equipment design process at the vendor level, and provide the end user with improved short-term operational guidelines and long-term strategies for future purchases and operation. Truck vendors recognize that the interaction between operator, seat, frame, suspension, tires and oil sands is unclear, and must be better understood before proceeding to next generation designs. Similarly for shovel manufacturers, the relationship between bucket/dipper motion, carbody, side frame, rollers, track and oil sands follow in the same vein."

Jan 1, 2002

By B. R. MacKay

Introduction The Corbin coalfield is one of the smallest, and at the same time one of the principal, producing bituminous-coal areas in southeastern British Columbia, and is unique on account of the great original thickness of one of its coal seams and the remarkable concentration of coal in a small area that has occurred through intense folding and faulting of the measures. These are such that the deposit has been referred to at times as "the world's thickest coal seam" and as" a mountain of coal." The determination of the number, thickness, and character of the seams present, and the structure, extent, and geological relationship of the several deposits, are of vital interest both to the operating company in its endeavour to evolve the most efficient method of mining these exceptionally thick deposits and to the Government in estimating the coal resources of the different fields. With the object of ascertaining these data the writer was assigned in 1930 to geologically map and study the Corbin coal deposit. A topographic map covering Coal mountain and the immediate vicinity on a scale of 1 inch =800 feet, with a contour interval of 25 feet, made by the Topographic Division of the Geological Survey, served as the base for the geological mapping.

Jan 1, 1931

Currently an Australian Standard for tunnel fire safety is being developed for road and rail tunnels. Other local guidance relating to tunnel fire safety that has recently become available includes publications by both the Roads and Traffic Authority and RailCorp of New South Wales. Internationally, the World Road Congress has completed its 2004 - 2007 cycle, which has resulted in a number of publications. International developments in rail guidance include a new European Standard regarding fire safety in railway tunnels that will come into effect in July 2008. In addition, the National Fire Protection Association committee NFPA 130 are in the process of revising their standard for fixed guideway transit and passenger rail systems, which is due for publication in late 2009. This paper outlines the status of these and other recently published relevant local and international fire safety guidelines and their implications for tunnel projects in Australia.

Jan 1, 2008

Bolivia, due to its turbulent past with a history of constant military coups, has given an image of complete instability to the foreign investor. The effects of this have been several fold, the major one resulting in a complete lack of exploration in modern terms since their revolution in 1952. What was overlooked by the foreign investor was the fact that revolution produced Agrarian Reform which is the foundation of the stability which Bolivia enjoys today. Another factor that is overlooked is the fact that its past history is one of vast mining fortunes having being made. Their political problems resulted in economic chaos in 1985 with an annual inflation rate of 26,000 percent. This resulted in the collapse of the government but the democratic process continued. Then came the so-called"South American Miracle" in 1986 when the government of Dr. Paz Estenssoro enacted an extremely harsh austerity program which consisted of the abolition of wage and price controls, the abolition of monopolies, the right to hire and fire, the weekly auctions of dollars and the free convertibility of currency which yielded a stable government with 8 percent inflation. This was followed by massive personnel reductions in the various mines and other industries.

Jan 1, 1991

By G. L. Smith

Central to the success of any mining company is the ability to manage capital investment effectively so as to ensure acceptable stakeholder returns within an overall strategic context. Critical to this process is the effective selection and implementation of a strategically aligned project portfolio that enables optimal resource exploitation while operating within mandated bounds and identified constraints. Consideration is given to the strategic long-term planning process, an investment prioritization methodology and specific tools and techniques based on the discounted cash flow philosophy.

Jan 1, 2007

By A. Jain

During sheet forming, metal experiences not only multi-axial load, it also undergoes strain path changes. For example, metal in the flange region may be drawn, may bend and unbend through a bead, before bending around a die radius, etc. Compression data were obtained from AZ31 sheet after pre-straining in compression along an orthogonal direction. The compression directions correspond to the sheet product (rolling-RD, transverse-TD, and normal-ND) directions. Three cases are examined: slip dominated deformation (ND) followed by twin dominated (RD or TD) deformation, twin dominated (RD or TD) followed by de-twinning (ND), and twin dominated (e.g. RD) followed by cross-twinning or secondary twinning (e.g. TD). Slip induced pre-straining simply hardens the material, while twin dominated pre-straining alters the texture allowing the material to either de-twin or re-twin upon changing the strain path. Polycrystal plasticity modeling has been used to predict qualitative features of the flow curves during strain path changes.

Jan 1, 2006

Being a geologist I intend describing the renaissance of the gold industry in Australia within its geologic framework; there is a geological pattern to the numerous gold projects which have been brought on stream over the past decade. We are now about midway through our third and largest gold boom which, at a peak of 7.5 million ounces is about twice the production peaks achieved in the preceding booms. From discovery in 1851 through 1870 we saw the first boom largely based on alluvial production in NSW and in Victoria at the great Ballarat and Bendigo Goldfields. The discovery of the Golden Mile in Kalgoorlie, Western Australia, underpinned the second gold boom in the period 1895 - 1915. On that basis the present boom should last through the next decade.   It has been a golden decade for Australian gold production. From less than ten mines in 1980 with production over 10 000 ounces and the largest, Telfer, with output of about 130 000 ounces we now find over 130 deposits being worked around the country today that produce over 10 000 ounces with the largest, Boddington, having an output of over 400 000 ounces. In total these mines produced an estimated 210 tonnes of gold in 1989 and we expect this year, 1990, that a new record production of between 240 and 250 tonnes will be set. This positions Australia in third place in the Western World behind South Africa #1 and the USA #2 and fourth in the world with the Russians holding second place overall behind the South Africans.

Jan 1, 1990

By Wils L. Cooley

Several aspects of coal mine safety-ground system operation are studied. Evaluations of two sophisticated ground-wire monitors are presented, along with a detailed report of development work on a modular ground-wire monitor. A portion of the report covers stray current flow in the safety-ground system, analyzing in detail conditions surrounding the generation of both dc and ac ground wire current. Considerable detail is provided concerning studies of mine ground beds. Additional progress is reported in the development of a. continuous ground-bed monitor, and new techniques are developed for the design of ground beds and their resistance measurement. New methods of accurately measuring electrical parameters of finite layered conducting structures are also reported. The effects of stray currents in ground beds is included. Touch-and step-potentials associated with mining equipment are analyzed, and methods are presented for determining earth voltage gradients around structures contacting earth. Instrumentation to determine gradients easily is suggested. Finally, an extensive effort is described dealing with lightning transients on open-pit coal mine ground systems. The nature of the transients, their expected frequency of occurrence, and the ways in which they damage equipment are analyzed in detail.

Jan 1, 1977

By Werner Unland, Nick Holl

"The paper presents the engineering design and experience gained so far with a dewatering system for an open-pit uranium mine planned at Key Lake in Northern Saskatchewan.The results of hydrogeological investigations preceding engineering exhibit an extensive unconfined overburden aquifer hydraulically connected with the underlying Athabasca Formation and basement rocks, both of relatively low hydraulic conductivity. The overburden aquifer is embedded in a bedrock trough, with the deepest depression between the planned pits. The hydrogeological data were used in a numerical dewatering model simulating groundwater flow atdifferent stages of the pit development.Based on the model results, the engineering design had to provide for different pumping rates, varying between 1.0 and 0.21 ms/sec. This problem was solved by using a double line pressure system. The design concept for the complete peripheral discharge system and the well design used for 26dewatering wells are discussed.Experience with reverse-circulation techniques applied for the construction of the dewatering wells is presented. Theoretical and practical considerations which led to the constructionof wells of different diameters are discussed.The design of the in-pit dewatering system provides for seepage ditches, horizontal drains, pit-bottom sumps and inpit dewatering wells where required."

Jan 1, 1980

Arizona copper mines produced nearly 67% of the nation?s copper in 2000, according to a report released by the Arizona Mining Association (AMA). This was a slightly larger share than in 2000 despite large reductions by one major copper producer and production cutbacks at several other facilities. In 1999, Arizona mines produced 64% of the nation?s copper. The report was prepared by economist George F. Leaming of the Western Economic Analysis Center in Marana, AZ. It also showed the copper industry had a $4.6-billion impact on the Arizona economy in 2000, a 26%decline from 1999. This is the lowest financial impact since 1973 and less than half the record reached in 1981of $9.6 billion. The decline is primarily due to a sustained low copper price and a slow-down in the US economy. The mining industry?s impact included combined direct and indirect contributions of $1.283 billion in personal income for Arizona residents, the equivalent of 43,000jobs. More than 5,000 of those jobs were in state and local government and more than 18,000 were in trade and ser-vice businesses. The copper industry directly employed fewer than 8,000 people statewide in 2000. This was down about 23% from 1999.

Jan 1, 2001

By K. L. Williams

The Bureau of Mines tested a prototype tapered-element oscillating microbalance (TEOM) dust monitor for measuring respirable coal mine dust. The monitor uses the inertial behavior of a vibrating element to measure the mass of sampled dust. Tests were performed to determine variability, drift, the effect of humidity, placement of collection filter, and element orientation during analysis, and comparability with gravimetric measurements of respirable coal dust. Variability was about 1.6 µg. Over about 26 h at 46 pct relative humidity, drift was very slightly negative. When the relative humidity was increased to 78 pct, all units showed a total positive change less then 40 µg over about 70h. Filter placement variation on the tapered element resulting from in- consistent sizing of the filter mounting bases caused significant error (up to 0.2 mg). In practice, calibration of the system for each new filter will eliminate that error. Orientation of the element during analysis did not introduce significant error, but care is necessary when mounting the canister that houses the element to avoid damping oscillation of the element. Dust tests were performed in an aerosol chamber using coal dust. Measurements made by the TEOM dust monitor agreed to within 10 pct of simultaneous measurements by gravimetric personal samplers.

Jan 1, 1986