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By Geoffrey C. Huggins

Diagnostic: tests were performed on a production ST-5A Load-Haul-Dump machine manufactured by Wagner Mining Machinery Company to evaluate and rank order noise sources. The diagnostic evaluation indicated that the major noise sources were the transmission, the engine, and the cooling fan. This phase was followed by implementation of recommended noise control treatments, which included vibration isolation of the transmission, a transmission enclosure, an engine enclosure, and modifications of the inlet to the cooling fan. The final step in the program was an underground operational period which began on 31 August 1976 at the National Gypsum Mine in Shoals, Indiana. The noise control treatments successfully reduced the LHD operator noise exposure by 7 dB(A), thus increasing its allowable operation time by a factor of 2.7. Actual measurements made underground using noise dosimeters have indicated that, during, a typical shift, the noise control treatments have reduced the fractional exposure to an allowable level. The report discusses the mechanical aspects of the LHD, its noise sources, the treatments applied, the final levels achieved, and field experience with the noise-controlled machine.

Jan 1, 1977

By Mike Tracy

This section of the Handbook deals with general principles to be evaluated in the development of a mining operation. It addresses the major issues that must be examined to fully evaluate a mining venture. Of course, one of the main topics to be evaluated is mine planning, which is covered in more detail in other sections (13, 17) of the Handbook and should be referenced in mine development projects. The topics to be discussed in this introduction include equipment and supplies, infrastructure, utilities, and project management. In any of the aspects mentioned, the current existing conditions at or near the mine site must be evaluated. This will include assessment of current use of utilities, infrastructure, housing, equipment suppliers, etc., as well as anticipated growth, both in the supply aspect of these systems as well as projected usage on these systems. After full assessment of both these aspects, an evaluation must be made as to the requirements the project will place on these items. Assessment must be made as to any up-grades required to bring the project on line, what impact the project will have on existing or expanded systems, and anticipated future growth impacts on support systems not only of the project but of other surrounding industry and urban devel-opment

Jan 1, 2008

This report describes the development of training materials for the operators of underground mining equipment in the underground metal and nonmetal mining industry. The objective was to determine the effectiveness and acceptability of these training materials and to provide the validated training materials to the industry. Ten modules were developed, based on industry need according to accident frequency, accident severity and exposure to the equipment. The final modules were an average of 20 minutes in length and used slides with synchronized narration on cassette tapes. Testing materials are included for use by the mines.

Jan 1, 1984

By James H. Aase

[This study provides data on the physical and hydrological makeup of the ,t hakes waterway system and forecasts quantities, traffic patterns, and ping cost of prospective bulk mineral commerce projected to be transported it. Factors affecting the shipping cost of iron ore, bituminous coal, imestone were quantified and integrated into a computer program that can d to estimate costs under varying sets of conditions. Combined ship of iron ore, bituminous coal, and limestone in 1995 were estimated at million tons. The cost of operating the U.S. vessel fleet for trans-ng an indicated 80 percent of this traffic tonnage was projected to be $163. 5 million.]

Jan 1, 1970

By Brad Bulow

Blasting is an essentially violent process aimed to disrupt and loosen rock for productive excavation. Some dilution of any ore present is the inevitable result. This makes blasting a dirty word to most geologists, particularly in narrow vein gold mines. A 1% increase in gold recovery may be worth $1 M extra revenue to a large mine.

Jan 1, 2000

By Gregory M. Dexter

Recent litigation in Pennsylvania between three coal-mining companies and a private water company resulted in the payment by the coal companies of the equivalent of about $500,000 to buy a new water supply to replace that which had been damaged by acid drainage from strip mining. An investigation of the relevant facts indicates that the water could have been treated by spending about $40,000 on equipment and $15,000 yearly for chemicals, labor, and power until the contamination could be reduced about 80 pct. The water company's supply, furthermore, had deteriorated largely by reason of dry weather before stripping was begun by the coal companies. Payment to the water company should not have exceeded $300,000 and could have been as low as $100,000. Strip mining of coal is common in Pennsylvania. The most important objection to it in Pennsylvania is generally acid pollution of runoff water. An outline of the methods, therefore, that could be used to reduce such pollution, to compare acid-contaminated waters, and to treat such waters to make them satisfactory for public and industrial use is worth-while. The watershed of the West P~M Water Co. covers about 4.5 square miles, 20 miles west of Pittsburgh, and has two 90,000,000 gal reservoirs sup- plying about 1,300,000 gal daily for public and industrial use of which 450,000 gal daily are for two railroads. The pollution arises from weathered derivatives of typical "Coal Measures"

Jan 1, 1949

By Bradley V. Johnson, Robert J. Timko, Edward D. Thimons

Water-jet-assisted cutting involves the use of a mechanical cutting bit in combination with a high-pressure water jet directed just in front of the bit tip. Such a jet can offer benefits in terms of improved cutting, reduced dust and fines, and improved bit wear. The Bureau of Mines, through a contract with the British National Coal Board, has researched the use of water-jet-assisted cutting on roadheaders. After several engineering design problems were overcome, this program led to the successful underground testing of these roadheaders. Today, more than 60 water-jet-assisted roadheaders are in operation around the world and numerous others are on order. This paper details the evolution of these machines and the benefits to be gained by their use.

Jan 1, 1987

By P. H. Morris

The exponential delta profile equation matches the profiles of a wide range of coal and metalliferous subaerial tailings deltas well, but the original model implies unrepresentatively low solids concentrations. A revision, based on analysis of the governing equations of mobile bed flows with high concentration values, has shown that for exponential delta profiles to form there must be quasi-steady, slowly varying flow and slow deposition as well as tailings with a log-uniform sorting-parameter distribution. Deposition on tailings deltas is slow and the flow in many natural streams and, by analogy, tailings deltas is quasi-steady and slowly varying; the assumption of such flow is justified by the strong congruence of the revised model and the available data. The predictions of the theoretical model are essentially unchanged but concentration and flow Froude number are now not explicitly limited

Jun 19, 1905

By S. J. Broderick

[Huge camp heaps coat. in-.n,- ta._ur nd o tons of coal :'efuse are a familiar sight in coa).--:1'_ni`l ; res io The;;' repre£e: t considerable economic loss, are very ~JZ':Si~i,tly, and tr:_ e u.: mach v lua-ble :price. Consequentl;;* their remcva7. is ,-,reatl:r de sir^~t~ a_." ar return that c,-u? be obtained would. be especially rel.co c to the coal T,-e "a_ste nat(~ria1 commrioes large pieces of bore cca1., lumps rf c12;', -)nd finer refuc3 coming from the 'acxcor~-, Tnc e'-:s: rr;I refuso contains some Food coal. Th1S coal and the better crams of _,)ore Pre t'--:e na.torials considered. in ohis in¬vestigotion. T'.-.r, heavier fractions of the vas ier,,refuse a rd. the large pieces of slate a n i roc _r contain little carbcnacaous r..aterinl -.nd axe ~vir¬ tually worthless ra'., :,atcria1. for activated carbon. In the E i 1i 11?'ar 1 dictrict~ n1ab a :1 ut irfl percent of the' coal mined is wa^,hed., and in district rc_a e -c-cnuatcs at the r..-ate of I to 2 Million tons a year?]

Jan 1, 1941

By C. C. Oosthuizen

Paper written on project work carried out in partial fulfilment of Technikon Practical Training Frank shaft is mining both Merensky reef and UG2 reef. The Merensky orebody is almost depleted and this was the reason for starting to mine the UG2 ore reserves. It was decided to mine the UG2 orebody with trackless equipment using a bord and pillar mining method. Frank shaft has been mining the UG2 orebody for nearly 5 years. The T-cut mining method was introduced to see if it could improve the grade of the run of mine (ROM) as well the extraction percentage.

Jan 1, 2005

By Seffen Leppla, Rolf Katzenbach, Matthias Seip

"Abstract The economic and safe design of deep foundation systems in difficult soil conditions is based on a reduction of construction material used, construction time spent, energy consumed and a high-level modelling of the soil-structure-interaction. The special foundation system Combined Pile- Raft Foundation (CPRF), in-situ load tests on the construction site and a sufficient soil investigation allow cost optimised constructions. In any case at challenging projects the observational method has to be applied for verification and quality control of the design. Regarding the 4-Eye-Principle as basis of the quality control management an independent peer review of the planning, design and construction phases is the guarantee for safety, serviceability and optimisation of all projects. Main execution standards for the construction of deep foundations based on the Eurocode 7 are summarised and discussed. The paper presents the basics of the safe and qualified design and construction of foundation systems including quality assurance. The application in engineering practice is shown on achallenging project of high-rise buildings with difficult boundary conditions.IntroductionThe construction of deep foundation elements in inner cities are special challenges due to the limited space for the construction works and the effects on existing buildings (Figure 1).An economic and safe design of deep foundation systems in difficult soil conditions is based on the following main aspects:•,qualified experts for planning, design and construction•,interaction between architects, structural engineers and geotechnical engineers•,adequate soil investigation•,design of deep foundation systems using the Finite-Element-Method (FEM) in combination with•,enhanced in-situ load tests for calibrating the soil parameters used in the numerical simulations•,quality assurance by an independent peer review process (4-eye-principle) combined with theobservational method if necessary"

Jan 1, 2014

By C. Hellar

A new dual-boom remotely controlled roof bolter was designed, fabricated, and then tested in an underground coal mine. Remote-control functions allowed complete bolting cycles to be performed on two booms with both operators located within protective cabs. Capabilities included 3-to 6-foot-long bolts in 5-to 8-foot seams, limited to bolts 20 inches shorter than seam height. Machine was in compliance with all regulations including dust collection, machine lighting, and permissibility.

Jan 1, 1979

By David J. Mack

A SURVEY and critical appraisal of published information about Young's modulus was originally made by the writer because of a complete lack of information about this very important quantity in works on mechanics, physical metallurgy, physics, and other sciences. It was felt that a comprehensive summary of such information about Young's modulus might be of general interest and may suggest new problems or lines of attack on other problems that involve E. Hence this paper has been prepared even though it is only a review, with no new ideas or experimental data. The references are only those used in assembling the paper. No attempt was made to compile a complete bibliography on the subject of Young's modulus. CALCULATION OF YOUNG'S MODULUS FROM THEORETICAL OR EMPIRICAL CONSIDERATIONS Many attempts have been made to compute E from theoretical considerations. The earliest calculations were probably those of Tomlenson (1883) and Southerland (1891), but Fessenden 41,42 made extensive calculations a few years later and arrived at the relationship: [2E = 78. 101 (_L V] where V is the atomic volume. In 1923, Peczalski,43 working from the same stand-point but with more information available on atomic structure, arrived at an identical relationship, which he expressed as: [E=B(m) 2] where B is a constant of value about 8 • 10 7, p is density and m is atomic weight; the atomic volume, of course, being m/p. Portevin44 immediately pointed out that while the equations of Fessenden and Peczalski were true of the common metals, they gave low values for the refractory metals with high moduli (Fig. I). He showed (Fig. 2) that much better concordance was obtained by means of an empirical equation of the form: [E _ KT'Vb] where K is a constant; T the absolute melting point; V, atomic volume, and a and b constants of value approximately I and 2 respectively. This constant K in the Portevin equation is not necessarily the same for all elements, as shown by Thompson.45 Other equations for E based upon theoretical considerations have been derived by Honda and Yamada49 and Lasareff. 50 The most recent calculations of elastic moduli based upon quantum mechanics are probably those of Fuchs.46-48 He extended the method of Wigner and Seitz for calculating the lattice energy and compressibility of monovalent metals and computed the elastic constants of lithium,

Jan 1, 1945

By Tuncel M. Yegulalp

This final report contains the results of all work performed under BOM Grant J0333905. A preliminary systems analysis of coarse-particle coal slurry pipelines as a haulage method for longwall mining systems was performed. Two exhaustive literature surveys on state-of-the-art longwall mining and slurry transport technologies were prepared. Two representative longwall systems were designed, one with conventional haulage and one with slurry haulage. These two systems were then compared on the bases of cost, safety, and reliability. The conclusions were that for the case of a two-face longwall mine, a coarse slurry transport system does not have a clear-cut cost advantage over a conventional (conveyor-hoist) system. However, indications were that a cost advantage could occur under different analytical conditions such as: (1) a larger scale mine, (2) if intangible benefits were quantified, and (3) if new generation technology rather than currently available technology were applied to the study. Budget and time constraints prevented exploration of these conditions.

Jan 1, 1982

By J. L. Gillson

Joseph H. Birman (Chairman, Dept. of Geolcgy, Occidental College, Los Angeles, Calif.) Many thanks to J. L. Gillson for so comprehensive a survey of the titanium sand deposits of the world. Over the past two years, the writer studied rather carefully some of the Cretaceous ilmenite deposits in New Mexico and Colorado, including the Sanostee deposit shown in Gillson' s map, Fig. 6. The deposits were geologically mapped and sampled, surveyed by magnetometer, and the Sanostee deposit was drilled. Moat of the genetic interpretations made by Gillson concerning the recent sedimentary ilmenites can be clearly read in the Cre-taceous deposits in New Mexico. The deposits are in marine regressive members of the Mesaverde group. The deposits trend within a few degrees of N 55° W and persistence of this trend through both distance and time (the deposits are in different members of the Mesaverde group) implies that the deposits are offshore bar accumulations. Heavy mineral content ranges from about 10 pct to more than 50 pet. Thicknesses are from 4 ft to as much as 20 ft, widths range from 150 to 600 ft, and lengths range from a few thousand feet to a few miles. All are locally or completely overlain by carbonaceous shale and thin coal. The deposits are strongly altered, and from X-ray diffraction the principal titanium alteration product appears to be anatase. Drilling of the Sanostee deposit shows that the alteration is not related to the present erosion surface but took place at the site of deposition and before burial by the overlying sediments. Iron oxide derived from the alteration cements the grains and is the chief coloring agent in the immediately overlying shales. In the Sanostee deposit, there is virtually no feldspar, the gangue mineral being almost exclusively quartz. Sorting is excellent, but the quartz grains are subangular to angular. Petrographic examination reveals that the angularity is not due to overgrowths. Therefore, short distance transport is implied. The mineralogical composition suggests a low relief granitic terrane as the source area. Feldspar may have been decomposed by weathering at the source, but an alternative preferred by the writer is that each of the deposits represents a long-term concentration site (for example a large sand bar) which was continually being deprived of light minerals by wave action and selective transport. Feldspar may have been mechanically reduced in size more quickly than the quartz, and thus its rate of removal may have exceeded that of quartz. Concentration of heavy minerals would thus occur until the marine regression removed the zone of maximum wave energy from the site. Chemical alteration would then become the most important process until burial by encroaching swamp deposits.

Jan 1, 1961

By William S. Gardner

It is certainly an honor to have been invited to address the Deep Foundation's Annual Meeting on such a vast and weighty topic as "Present to Future Design Considerations of Deep Foundations." Acknowledging the enormity of this 30-minute assignment, I hope to at least scratch the surface of the topic deep enough to generate some thought and reflection. Design considerations, be they current or future, bring to mind a number of important subtopics which comprise the design process. As shown by Figure 1, a flow chart of this process describes, in general terms, the sequence of a deep foundation design.

Jan 1, 1991

By J. E. Friant

The Mini-DiscTM cutter drill bit is a radical design departure from the traditional tri-cone rockdrill bit. Miniature disc type cutting tools as small as 3.25 inches (82.5 mm) diameter are fitted to a bit body to cut individual concentric kerfs. The action is the same as that commonly used on large tunnel boring machines but miniaturized. The high performance rate and efficiency of a disc cutter are the result of producing a large proportion rock chips rather than sand or powder. The Mini-DiscTM drill bit, referred to as the “Disc Bit” has other unique features as well. It can be re-greased between runs. It can be rebuilt in the field in about 15 minutes, cutters can be replaced and the Disc-Bit appears to require less down hole hydraulic power than conventional bits. Thoroughly tested in the laboratory, the bit has recently been undergoing field trials in well drilling, blast hole drilling and shaft drilling. As any engineer knows, the laboratory can not shake out all the problems but it eliminates the more glaring weaknesses. Performance results have been exhilarating, and a few mechanical problems were discovered and largely overcome. This paper is a progress report.

Jan 1, 1999

By N. Malakondaiah

Several growth chamber and laboratory experiments were conducted to study the germination behavior of plant species on mine spoils and plant growth responses to nutrients on spoils and topsoils. Experiments were conducted to study the germination potential of some native and introduced species under various conditions. The seeds of green needlegrass, side oats grama, thickspike wheatgrass, crested wheatgrass, birdsfoot trefoil and emerald crownvetch were less tolerant, whereas those of alkali sacaton. durar hard fescue, slender wheatgrass, yellow sweetclover and alfalfa were most tolerant to the sodic mine spoil conditions. Addition of leonardite improved the germination potential of some of the poor genninators. Slender wheatgrass and yellow sweetclover were used as test plants to study the fertility status and productivity potential of stockpiled topsoils and spoils collected from Center. Glenharold and South Beulah of North Dakota. The topsoils were neither saline nor sodic but low in N and P. The spoils were neutral to alkaline with SAIL of 12-32, EC of 1.8-5.5 mmhos/cm, Olsen&apos;s P< µ4g/g, and total N <0.07%. Application of N and P together to the topsoils increased the yield of wheatgrass and sweetclover by 88% and 70% of their respective maximum yields, whereas near maximum yields were obtained for both the species by the same treatments to the spoils. The average yields on topsoils were higher than the yields on spoils. The concentrations of major nutrients were higher in plants grown on topsoil, whereas the opposite was true with the concentrations of Mn, Zn, and Cu. Growth chamber experiments were also conducted to study the growth responses of alfalfa, oats and slender wheat grass by the application of Mn and Zn to a sodic coal mine spoil which was previously used for pot culture experiments. Significant growth responses to Mn and Zn were observed in alfalfa but not in oats or slender wheatgrass. Fertilizing the spoil with Mn along with NPK increased the yield of alfalfa to 85% and with Mn + Zn to 99%. Growth responses and plant composition results of this study confirm that the application of major nutrients to spoils can accentuate Zn and Mn deficiencies in some plants.

Jan 1, 1982

By A. E. Anderson, H. J. Hilll

Laboratory data for 155 field muds and 77 .shales have been used to develop correlations to estimate the net streaming potential component of the SP. Analysis of these data and comparison with field tests show that streaming potential corrections must be made to obtain an accurate estimate of the electrochemical potential for use in the determinntion of formation water resi-iiviy. The self-potential curve is related to formation water resistivity, and considerable effort within the oil industry has been directed toward clarifying this relationship. The Schlumbergers and Leonardon1,2 recognized that two types of potentials, electrochemical and electro-kinetic, resulted in the net potential variation in the borehole. Most of the later papers have dealt with the electrochemical component and its controlling parameters. The investigations of Wyllie,2" Salisch&apos; and Moore5 provide the most extensive sources of data on streaming potentials across mud cakes. These authors observed streaming potentials of sufficient magnitude to be of critical importance in SP interpretation, if it is assumed that streaming potentials develop only opposite permeable beds. Streaming potentials across shales have been reported by Schenck and by Gondouin, et al.7 Since SP magnitude is the difference in potential opposite shale and sand beds, these authors suggested that the net streaming potential component may be negligible. The present investigation was initiated to evaluate empirically some of the parameters controlling the magnitude of the net borehole streaming potential and to determine whether useful relations between mud properties and net streaming potential could be established. Field muds were used in this investigation. These muds were characterized by the amount and type of chemical treatment utilized for five days before Sampling. Filter loss, mud resistivity, mud density and filtrate resistivity were determined for each mud with conventional methods and apparatus. Mud filtrate pH was estimated with Hydrion pH paper for the appropriate range. Streaming PotentIals Across MuD Cakes Commercial calomel-saturated KC1 electrodes are subject to potential changes attributed to contamination of the very small fiber-tip bridge by particles of clay from the drilling mud.3 To minimize this difficulty, a large diameter bridge (Fig. 1) was constructed with saturated KC1-agar gel and a filter disc of microporous porcelain. Experiments showed that streaming potentials across this bridge are less than 0.2 mv at pressure dif-

By K C. Williams, A W. Roberts, J D. Prigge

For stockpile design, the flowability and structural interfaces are critically dependant on the stress conditions throughout the pile. Historically, the predictive methodologies for stress determination have been too conservative, which adds inefficiency to the stockpile reclaim interface selections, especially for live reclaim stockpile systems. In addition, accurate pressure profiling throughout stockpile is essential to correctly design the stockpile support structures, which are buried within the stockpile. Such buried structures include trestle legs or columns to support load-out conveyors or the roof of bulk storage sheds. Improved methodologies with respect to the development of the hoop stress condition which exists in material ædrawn-downÆ within the stockpile has been developed. This hoop stress approach has significantly improved the live capacity prediction to over 90 per cent accuracy and improved rathole structure prediction within live reclaim stockpiles. Additionally the methodologies in estimating the vertical and circumferential stress variation acting on buried stockpile structures have been significantly progressed, with experimental testing shown good agreement with the theory.CITATION:Williams, K C, Roberts, A W and Prigge, J D, 2013. Recent developments in stress analysis and live reclaim prediction within iron ore stockpiles, in Proceedings Iron Ore 2013 , pp 501-510 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013