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By Kot F. Unrug

In the premining stage of engineering design, the only available data are obtained from core drilling. It is often not sufficient for a realistic design of strata control. During the development, an access to the geological formation is created, enabling in situ testing. Obtained data can be utilized accordingly to improve preliminary design. The available methods for testing are described with emphasis on their application for a longwall system. The optimum design ensuring continuous operation of the high output longwalls is critical because their downtime is very expensive. Optimization of ground control measures also has the potential for substantial savings by elimination of unnecessary support.

Jan 1, 1994

By Campbell Brown GA

IN 1904-5 diamond drilling operations in the Mount Morgan mine proved the presence of some inillioils of tons of rich, copper-gold ore, averaging about 45% to 50% silica and 22%Fe as sulphide. To smelt this ore in blast furnaces, without previous concentration, large quantities of basic flux.were required. Unlimited quantities of cheap, limestone, were available at Marmor, on the GladstoneRockhampton railway, 50 miles from Mount Morgan, but the supply of iron flux was a more difficult problem. Smelting operations started, with one' furnace in January, 1906, using as flux low-grade sulphide ore fro:m. the mine, containing very little silica. When the second, furnace was blown in this was supplemented by ironstone from, small aeposits in the immediate district. It was recognized that these sources of supply would be insufficient to keep the full plant going after the third furnace had been blown in. Accordingly, the deposits at Eabra and Mount Etna were opened, neither of which proved capable of supplying the quantity required viz, 1000 tons per week. Negotiations were meanwhile being conducted with the Marble Island Iron and Limestone Co. to obtain the right to mine at Iron Island, where a sufficiently large deposit was known to exist. Shipments from this source commenced in January, 1907, and ceased at the end of July of this year, when the metallic flux from...

Jan 1, 1912

By F. Mielli

Ranging between 20% and 40% of the typical mining operational costs, energy in mining operations is a growing concern for the industry. However, this concern is a complex, multi-faceted variable that involves government regulations, societal pressures, cost and competitiveness. A mining company successful in energy efficiency is becoming the standard of a successful company. The suggested energy strategy in mining and mineral processing operations has to follow a well structured approach that entails the following: ? Understanding where energy is being used and why, ? Recommending and implement energy conservation measures, ? Driving visibility to targets and results, ? Leveraging the energy spend across the enterprise, ? Developing a robust energy and sustainability strategy.

Jan 1, 2012

By Richard P. Reiff

"The Facility for Accelerated Service Testing (FAST) program has been involved in numerous rail wear tests since its inception in 1976. A number of specialized tools have been developed to aid in assessing specific performance parameters including gauge face wear, head height loss, metal flow, head area loss, hardness, and welded rail end batter. The layout of a test site, including position in curve, number of measurements per rail, and train operation must be properly controlled/monitored to provide valid wear comparisons.This paper will provide an overview of the above-mentioned tools and techniques. In addition, a summary of recent test results from FAST, including information on head hardened rail investigations, will be provided. A set of guidelines for establishing a revenue service field test site will also be provided to aid users in performing evaluations of their own.IntroductionBackground of Rail Wear Testing at FASTThe Facility for Accelerated Service Testing (FAST) located at the Transportation Test Center, (TIC), Pueblo, Colorado has been involved with testing of rail since program initiation in 1976. A huge data base of rail wear information has been gathered from FAST operations under a variety of rail metallurgies, lubrication conditions, and measurement techniques. Attempts at obtaining meaningful rail wear information from early (1976-1978) FAST rail wear data was hampered by two main factors: (I) measurement techniques were insufficiently accurate for the amounts of wear being experienced, and (2) the lubrication was not sufficiently controlled to obtain uniform conditions for a sufficient measurement time period.Subsequent test periods were operated with improved measurement techniques and controls that ensured statistically valid data. The policies and conditions that permit accurate rail wear assessment will be reviewed and outlined in this paper, along with some specific TIC and field examples that will allow the user to improve the accuracy of a field rail test on their own operating property."

Jan 1, 1988

By John A. Herbst, Alexander Potapov, Xiangjun Qiu

"High Fidelity Simulation is a name applied to the use of first principles modeling tools including Discrete Element Modeling (DEM), Computational Fluid Dynamics (CFD) and Discrete Grain Breakage (DGB) to mathematically describe and study processing systems. Over the past few years, significant advances have been made in High Fidelity Simulation applications, particularly as many mineral processors have been drawn to the study and use of DEM of grinding mills for optimization purposes. This presentation provides an introduction to High Fidelity Simulation, with an emphasis on DEM. It will include insights into current applications of these tools including the optimal design (wear and throughput) of mill lining systems and media selection, the analysis and design (flow and efficiency) of the back-end of grate discharge mills. Advantages of full mill simulations versus individual sub-process simulations will be demonstrated for a SAG mill with different discharge system designs.INTRODUCTIONHigh Fidelity Simulation is providing mineral processors with the opportunity to analyze the behavior of mineral processing equipment from a fundamental or microscale point of view. In the past complex phenomena such as tumbling mill grinding had to be analyzed using black box tools such as residence time distributions for transport and classification functions for passage of particles through grates; while breakage had to be analyzed using PBM models who derived their form from theory but required direct measurement of kinetics. Today with the help of DEM, CFD and DGB these can be analyzed at a very fundamental level.The key element of DEM simulation is the application of Newton’s laws of motion to individual objects or discrete elements. Using this simulation method one can describe the position, velocity (both translational and rotational) of all objects and the transfer of momentum to other objects (Mishra and Rajamani, 1992; Cleary, 1998; Nordell et al, 2001)."

Jan 1, 2003

By Walter E. Vanderpool

Full scale load tests are frequently performed immediately prior to deep foundation construction to verify the design assumptions. Occasionally, load tests are performed during design development and applied to the final design for critical and non-redundant structures. We believe that full scale load tests can be very valuable and economical for projects, especially in a geologic environment where the record of full scale load testing is very limited or non-existent. The load testing for the Utah Transit Authority?s Airport Light Rail Trax project provides an example of the advantages of a load test in design development. The savings realized by the owner was in excess of $800 thousand dollars.

Jan 1, 2011

By Kazimierz Gwizdala

In recent years, in Poland the ATLAS piles have been successfully applied for some constructions near Gdansk. The piles have been used as foundations for housing and another areas of civil engineering, in delta Vistula geotechnical region, characterized by weak, highly compressible soils represented by mud and peat, lying in sub-surface layers, several meters thick. Usually below are dense sandy soils or gravel. In all cases, the base of ATLAS piles rested on sandy soils. The analysis of pile bearing capacity has been discussed and verified by static pile load tests (SPLT). The load-settlements characteristics obtained were satisfactory. In the paper, the results of geotechnical investigations as well as calculations and load tests are shown. The ecological aspects of ATLAS piles application within highly urban areas of the cities and complex geotechnical conditions are emphasized.

Jan 1, 2006

By I. R. Ward

"The need for energy conservation has been of increasing concern since the early 1970's, when the cost of petroleum based energy began to escalate rapidly and security of supply became uncertain. The cost of energy from alternative sources has also increased due to development costs and environmental restrictions.These developments have had a serious impact on the mining industry, which is energy intensive. The impact is magnified as lower grade ores are treated, and more energy is consumed per unit of product. In many cases increased operating cost is not compensated by the rise in product selling price.The magnitude of energy consumption in the mining industry is indicated by recent studies conducted in the U.S.A. and Canada. Based on 1970 figures, it was reported that the production of 1 ton of copper in the U.S.A. required 111. 8 x 106 BTU of energy, of which 60. 7 x 106 BTU (54.3%) was consumed in mining and processing (l)The survey of Canadian mills, conducted by CANMET and reported to the CMP meeting of 1978 (2), showed the following milling energy consumption figures (approximate averages):"

Jan 1, 1981

The major copper orebody at Mount Isa is being extracted at a rate of four million tonnes per year. The method used requires an equivalent rate of back filling with (mainly) cemented fill. There were three major incentives for developing this mining system. The first was the prospect of high ultimate recovery of the orebody. The target is 100 per cent recovery. Also the proposed stoping layout appeared to offer significant advantages in development and production costs. Finally, extensive subsidence above the northern end of the orebody could have disturbed permanent surface installations and jeopardised a possible future open cut. The full implications of this ambitious strategy were not apparent in the early years. Now, after 12 years of production the benefits are being realised and they can be weighed against the costs. Probably the most interesting result which comes from this analysis is the significance of cutoff grades and dilution factors in balancing mining and filling rates.

Jan 1, 1980

By AIME AIME

THE following paragraphs comprise such information as the Secretary has been able to obtain concerning the members and associates whose deaths have been reported. Further particulars or corrections of errors, and biographical data concerning deceased members or associates not already noticed in this way, are solicited. [SECRETARY'S NOTE.-All of these notices have been revised, and some of then have been more or less completely prepared, by me. To those which contain more particularly the expression of my personal feeling, my initials have been appended. The labor of preparing or editing these paragraphs has been in many respects both welcome and interesting, on the one hand, and sorrowful, on the other. In going through the list, I have repeatedly felt like one who, visiting the Morgue, suddenly comes upon the pale face of a dear friend, of whose death lie was not aware ; and, even when this fact was known to me, the work of recording it has brought upon me a flood of recollections, almost preventing the discharge of that official duty. The list for 1907 seems to me to he peculiarly sad, comprising, as it does, so many sudden deaths by violence or accident, so many veterans, removed too soon, and so many young men whose early departure impoverishes the future, even more than the present. Probably, this feeling on my part is largely due to the circumstance that the increased membership of the Institute necessarily in¬volves an increase of the annual death-list. Probably, also, it is connected with the circumstance that during the first years of the history of the Institute-say from 1871 to 1880-it was joined by men of all ages, and that the death-rate is consequently now above the average which would result from the normal annual addition, principally of young men. And finally, I must admit that, as one of the original members of the Institute, and practically connected with it for nearly thirty-seven years as Acting President, President or Secretary, I am peculiarly impressed and depressed by the successive deaths of those who were my associates in the years of its early struggles and triumphs. I do not wish to inflict upon my younger colleagues the melancholy reflections of an increasingly lonesome old man. In fact, my prevailing mood concerning the Institute is not at all melancholy, but triumphant and hopeful. If I may be permitted to preach at all, I would enforce, from the texts given below, a moral which many of them declare so forcibly as to preclude the necessity of expository enforcements-namely, the duty of every one of us, old or young, to give to his brethren, as he goes along, and without waiting for some future occasion for a comprehensive and monumental contribution to technical literature, the results of his observation and experience. When I look at this list of names, my personal sorrow over many of them is drowned in my professional reflection as to each and all-How much has died with

Jan 1, 1908

Surface mining and reclamation of a southeastern Ohio site with sandstone-shale overburden resulted in (as compared to premining levels): 1) runoff volumes and peak rates that increased by a factor of from 2 to 10 during mining and after reclamation, 2) destruction of the "aquifer" perched on the underclay of the mined coal bed and gradual, but, as yet incomplete redevelopment of this aquifer after reclamation, 3) no immediate effect on another, lower perched "aquifer", 4) up to 100 times greater sediment concentrations in runoff. Results were influenced by increasing annual precipitation amounts through the period of record; 1978, 1979, and 1980 (postreclamation years) experienced precipitation amounts approaching or exceeding long-term normalcy for the area. Part of the reason that the site produced more runoff after reclamation than before mining is that the premine condition was one of an open, porous soil under woodland, while the postreclamation condition was one of a compacted, bulldozed soil. Sediment concentration results were influenced by failure of the postreclamation erosion control system and by a series of detention reservoirs above the stream monitoring station.

Jan 1, 1983

By E. H. Jr. Dix

THE use of magnesium as an alloying element in aluminum alloys has been limited, in general, to comparatively small quantities. In duralumin-type, strong-aluminum alloys, magnesium is present to the extent of ½ to ¾ per cent. and various grades of Magnalite and the "Y" alloy of the National Physical Laboratory of England contain up to 1 1/2 per cent. In this country small quantities of aluminum alloy sheet containing 4 per cent. magnesium are produced commercially. All commercial aluminum contains sufficient silicon to convert a portion of the magnesium added to the compound Mg2Si. It is well known that the solubility of both magnesium and magnesium-silicide decrease with decrease in temperature. It is, therefore, impossible to separate the age-hardening effect of the magnesium-silicide from that of magnesium, except by the use of aluminum of such high purity that the silicon content is negligible. The present paper is the fifth1, 2,3,4 of a series from the laboratories of the Aluminum Co. of America reporting the results of investigations of the equilibrium relations in aluminum-rich alloys made from the high purity aluminum manufactured by this company .5

Jan 1, 1929

By Philip C. Tully

This bibliography contains 3,062 different citations to technical and scientific literature about helium and alpha-particles abstracted by 13 abstract service publications during 1963. Multiple subject classification has increased the total number of entries to almost 5,000. Helium citations are listed by 23 major classifications. The number of subclassifications has been greatly increased to minimize the time required for literature search. The use of automatic data processing has been extended in compiling the bibliography.

Jan 1, 1970

By C. Haycocks

The problems caused by interaction in multi-horizon mining are world wide and are not limited to the coal industry. These problems will continue to increase as mining of new seams multiplies and replaces production from mined out horizons. Interaction problems are particularly evident in the Appalachian coal fields which contain many mineable, contiguously placed coal seams. Selection of the mining sequence of these seams, historically and currently, is based primarily on considerations of seam ownership, availability, and economics. Experience has shown, however, that mining any seam can seriously affect subsequent operations in coal seams both above and below the one being mined. This interaction effect is often detrimental to the recovery cost and safety of mining the subsequent seams. Designing to avoid or minimize interaction effects represents a major challenge to the modern coal mining industry and therefore is the focus of this research. In an effort to evaluate past interaction effects and provide guidelines for future mine design, interactive ground control problems were categorized into four areas. These are pillar load transfer, massive interseam shearing, subsidence and pressure arching effects. To facilitate research, each of these areas was studied separately although in reality these subdivisions are arbitrary and have considerable overlap.

Jan 1, 1983

By C. H. Herty

"The work on the physical chemistry of steelmaking, as carried out at the Pittsburgh Experiment Station of the United States Bureau of Mines in cooperation with Carnegie Institute of Technology and, the Metallurgical Advisory Board, has covered a series of fundamental studies on the action of oxygen in liquid steel and the application of the findings to open-hearth operation. The staff has varied from 14 to 23 men per year, some of whom have been Bureau of Mines physical chemists and metallurgists, others research engineers of the Metallurgical Advisory Board, and the remainder graduate students employed as research fellows at the Carnegie Institute of Technology. The work on the laboratory studies, and particularly on slag systems, has been in charge of G. R. Fitterer, associate metallurgist, Bureau of Mines, while the plant work has been under the direction of C. F. Christopher, research engineer of the Metallurgical Advisory Board. In all, some 16 physical chemists and metallurgists and 24 research fellows have taken part in the experimental work. Advantage has been taken of the opportunity for cooperation with the University of Pittsburg to have certain phases of this program made the subject of graduate work, particularly the laboratory studies on the deoxidation of steel with manganese-silicon alloys.The general method of studying oxygen has been, first, to determine the solubility of the various oxides in liquid steel. To date the solubility of Fe0 in steel has been determined, over a wide temperature range.3 The straight-line relationship in the plot of solubility versus temperature indicated that under a slag of 100 per cent Fe0 the oxygen was present in the steel as dissolved FeO. A further conclusion drawn from this work was that the solubility of FeO in the metal was proportional at a given temperature to the mol fraction of Fe0 in the slag if the slag contained a large excess of basic constituents. This result was determined from a study of the solubility of Fe0 under slags containing lime and iron oxide in various proportions. These data have been used extensively in determining the saturation of a bath of open-hearth steel under any conditions of slag composition, and results to be given later showed that the solubility curves are consistent with the results obtained in practice."

Dec 1, 1930

Despite the current economic downturn that is now decimating iron ore production, Minnesota?s mining operators remain optimistic about the long-term prospects for the industry. Reflecting this optimism, the development of several new mining projects continues in the state. The future of mining in Minnesota was the featured topic at the combined 82nd Annual Minnesota Section of SME Meeting and 70th Annual University of Minnesota Mining Symposium. More than 500 mining industry professionals, including engineers, executives, mining managers and equipment suppliers from the around the world, attended the meeting, which was held April 14 and 15, 2009, in Duluth, MN. The combined meeting featured a keynote session with three distinguished speakers plus a panel discussion by representatives from several of Minnesota?s taconite producers. The keynote speakers were Curtis Clark, president and chief operating officer, Behr Dolbear, who gave a presentation on the ?State of the Mining Industry.? Phil Newman, chief operating officer, CRU Strategies, spoke about challenges facing the mining industry and James A. Skurla, acting director, Bureau of Business and Economic Research, Labovitz School of Business and Economics, University of Minnesota Duluth, discussed the importance of mining to northeastern Minnesota?s economy. The taconite producers panel discussion included Jonathan Holmes, vice president and operations manager, ArcelorMittal; Ed Latendresse, vice president and general manger, Hibbing Taconite; John Tuomi, vice president operations services, United Taconite and Mike Mliner, vice president and general manager, Northshore Mining. The mangers provided updates on their respective operation The meeting included concurrent technical papers sessions on mining, processing, environmental and nonferrous mining. The sessions included technical papers that provided information on the status of a number of new mining projects in the state. The conference also offered a SME short course titled ?The basics of iron mining.? A tradeshow that featured about 100 companies and organizations offering products and services to Minnesota?s mining industry ran in conjunction to the conference. It was estimated that more than 900 people, including conference registrants and special invited guests of the vendors, attended the tradeshow opening reception. This was the largest trade show in many years. The Minnesota Section of SME also held its annual business meeting during the conference.

Jan 1, 2009

J. H. Lord (Geological Survey of Western Australia): During the last few days in Kalgoorlie here we have heard on various occasions of the great job the mining engineers have done persisting against rising costs and increasing salaries without a rise in the price of gold. I think it has been somewhat overlooked that it has been difficult to find additional ore as well. I consider that geologists also should be commended on their action in persisting to search for more orebodies. This goes on in any mining community, but in Kalgoorlie in particular, I believe, over the last few years that it has been more difficult all the time to find additional orebodies and the Companies are calling for higher grades to offset the economic condition. I feel that this paper by Mr. Finucane shows that the geologists have persevered on an idea and discovered that they can find additional orebodies in the calc schist where previously it was thought that these did not occur. This has added many tons to the ore reserves, and although it is not very significant at the moment, the significance will probably improve as more work is done.The whole thing has shown us the importance of economic geology. Mr Finucane has had many years of experience here and he has given us a very able exposition of the economics of ore finding, and there are not many questions that one could pose to him, because most of the information he presented is obviously fact borne out by drilling, underground development and lining up the ore channels. He did briefly touch on ore shoots-the Oroya shoot and several others. It would be very good if we could, and I feel sure...

Jan 1, 1965

Caving of the second lift of the E26 orebody at Northparkes Mines was monitored with a comprehensive package of instrumentation, including an ISS seismic monitoring system. Seismicity was collected by an array of 19 triaxial accelerometers and 9 uniaxial geophones, giving a high quality seismic data set. The seismic response to block caving at Northparkes has been divided into two papers. The first paper focuses on the seismicity during undercutting. The second paper deals primarily with the seismicity during cave propagation during initial cave production. In this paper, traditional seismic monitoring concepts are applied to seismicity during cave mining. More than 40 000 seismic events were recorded during cave undercutting between February and January 2004. Events up to local magnitude +1.3 were recorded near the mine during undercutting, with event rates of up to 500 per day. Analysis of frequency-magnitude distributions, S-wave to P-wave energy, and temporal variations in event magnitude all gave insight into the seismicity recorded. In addition, a new technique, called apparent stress time history, was shown to be sensitive to stress change from undercut blasting, and useful to identify significant periods during cave development. A significant difference was identified between the cave back location and the halo of seismic events above the cave. Throughout the undercutting, the a seismic zone of loosening was typically 50 to 70 metres in vertical thickness. Based on the seismicity, a stress driven rock mass failure model is proposed. Early in the undercutting, seismicity and movements in the seismogenic zone were directly triggered by stress change from undercutting. Towards the end of undercutting, seismicity was virtually uncorrelated with undercut blasting, and likely due to the onset of cave initiation.

Jan 1, 2008

By Denis Labrie

Le minage en profondeur sous contrainte modérée à élevée présente de nombreux défis aux opérateurs et aux ingénieurs de mine notamment au niveau du contrôle de terrain et de l?environnement minier souterrain, pour assurer la sécurité des travailleurs sous terre et la continuité du cycle d?opération. Des conditions de contrainte élevée signifient une pression accrue au front de taille et sur les structures minières tels les piliers de mine et les fins de zone, un risque de rupture violente ou de coup de toit plus élevé, des zones de rupture plus grandes au pourtour des excavations, des charges accrues sur le support de terrain, etc. Le présent article fournit un aperçu du travail fait à l?intérieur du Programme de Contrôle de terrain de CANMET au cours des sept (7) dernières années, entre 1995 et 2001, pour comprendre et suivre l?évolution des niveaux de contrainte à l?intérieur des structures minières. Les propriétés déterminées en laboratoire sur des échantillons rocheux et les prévisions effectuées au moment de la conception sont comparées avec les observations effectuées en chantier à la paroi des excavations et à l?intérieur de la masse rocheuse. La plupart des cas discutés ici montrent une corrélation satisfaisante entre les observations effectuées en chantier d?une part, et les résultats d?essai obtenus en laboratoire et les calculs réalisés lors de la conception d?autre part. Ces observations peuvent donc être considérées comme des moyens relativement sûrs pour vérifier et suivre l?évolution des niveaux de contrainte présents à l?intérieur des structures minières.

May 1, 2002

By C. McAllister, D. Preece, J. Berendzen

The Multiple Blasthole Fragmentation (MBF) model was developed recently and has been reported in previous papers. The MBF model accepts inputs from the blast design, such as: location and orientation of each blast hole, stemming length, blast hole diameter, multiple decking, bench height, initiation sequence, etc. It models the effect on fragmentation of delay timing with its associated scatter for each blast hole. MBF has a statistical modeling capability for geological random variation of the attenuation of particle velocities. Also simulated is wave reinforcement due to the interaction of simultaneously arriving waves or diminishing cooperative contribution from long delay intervals between charges.

Jan 1, 2016