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By Thomas O. Meyer

Laboratory test results are presented for the determination of elastic modulus made with the NX borehole jack. Determinations were made in massive pieces of aluminum so as to satisfy conditions of linear elasticity, homogeneity, and isotropy. Results indicate a large discrepancy (approximately 200 percent) betwen material modulus as determined by laboratory block-loading tests and that indicated by the jack under relatively ideal circumstances. Effects due to interface friction, finite block size, incomplete plate-bore contact, and other factors were examined and found not to be significant. Finite element results indicate that assumed loading conditions for the jack differ from those actually occurring, at least in materials of high elastic modulus (approximately 10 million psi), such as quartzite.

Jan 1, 1974

By Jinwu Kang

The hydraulic turbine blade of the matensitic stainless steel (Cr13%,Ni5%,Mo1%) is a kind of large and curved shape, which is susceptible to deformation in both casting and heat treatment processes. The coupling analysis of heat transfer, phase transformation and stress in heat treatment process of the turbine blade for Three Gorges Project is carried out by using Deform-3D software. Its temperature fields, phase fields and stress fields in heat treatment process are obtained. And its deformation is predicted. In the cooling process of normalizing, the blade exhibits relatively large deformation. Based on the stress analysis and deformation prediction in heat treatment process, an algorithm for the determination of reverse deformation of the blade casting in heat treatment process is presented. And the reverse deformation distribution of blade is obtained.

Jan 1, 2010

By W. A. Stickney

This report summarizes the results of laboratory tests of five samples of low-grade phosphate ores from Idaho. The laboratory test work has demonstrated that by grinding, desliming, and flotation a portion of the siliceous gangue can be removed. The highly carbonaceous ores responded successfully to treatment after preroasting, to produce a plus-30-percent-P205 product. It has been found that highly siliceous ores, as represented by the samples treated, are more readily amenable to concentration than ores high in calcium carbonate. Of the five samples tested, four were amenable to concentration to a product containing over 30 percent P205. One sample, from the Conda, second bed, was not amenable to mineral-dressing treatment to produce a plus-25-percent-P205 product.

Jan 1, 1955

By R. H. Batey

"The process control and cost of monitoring mining slurries is normally accomplished using a continuous mass flow system, conventionally embodying a volumetric magnetic flow meter and nuclear density meter. DuPont’s Maxville Mine at Starke, Florida, USA was chosen to examine costs associated with performance of a nuclear density meter. Since it is typical of many mid-sized establishments and has a long history in their use. The published accuracy under ideal conditions of a nuclear density meter is ± 1.0%, but in practice considerable ambiguity of cost in annual production implies ± 2% at best. Using such accuracy in a 400mm (16”) pipe carrying zircon slurry at 75,000 tons/day, the cost of ambiguity, together with initial and running costs, amount to nominally $962,000 per year.Such cost leaves much to be desired. This paper describes an unique continuous, direct mass per unit volume Density Meter used for mining slurries in pipe sizes up to 1000mm (40”), which significantly reduces the cost of ambiguity of measurement and running costs. At the same time the disadvantages of nuclear devices are obviated.In an effort to reduce costs, a 400mm non-nuclear Density Meter was installed at the DuPont Maxville mine. A typical on-site accuracy can be shown to be ± 0.285%, whereby the cost of ambiguity, initial and running costs in the example above shows an annual improvement of $78,660, a reduction of over $880,000 per year.Even higher cost savings may be demonstrated with mass flow systems having gas entrainment compensation. Unlike nuclear and other inferential density meters, the signal quality of this non-nuclear Density Meter is totally unaffected by entrained gas found in mining slurries. This non-nuclear density meter is then ideally used with a vortex velocity domain sonic flow meter, and provides for the first time compensation in wet density or dry % solids, as well as wet or dry mass flow of mining slurries with entrained gas, resulting in enormous reductions in cost ambiguity."

Jan 1, 2013

By Richard S. Watt

The Bureau of Mines is often called upon to analyze the demand for various minerals and fuels and to make projections of the future demand. Because minerals and fuels are raw materials and because the demand for raw materials [pends] on the demand for finished goods, these projections are usually [conned] with derived demand rather than final demand. In order to obtain quick [d] reasonably accurate analyses of the demand for mineral commodities, the [reau] developed a method and has used it successfully (31).4 To illustrate the [thod], this report presents a full analysis of the demand for a mineral commodity with enough general theory to permit application of the method to any mineral. Sodium chloride (common table salt) was chosen as the subject of the analysis because the demand for it is less complicated5 and permits a simple application and clear presentation of the method.

Jan 1, 1962

By Ben Aleck

The objective of this program was to adapt Space Shuttle technology on high-performance spherical pressure vessels to cylindrical pressure vessels. Specifically, a cylindrical aluminum liner overwrapped with fiberglass filaments and prestressed by yielding the liner under a sizing pressure was to be replaced by a higher strength-to-weight ratio steel liner overwrapped with a higher strength-to-weight ratio filament. The steel was cryoworked stainless steel and the new fiber was Kevlar 49. In addition, the heavyweight ends of the aluminum liner were to be replaced by thin-walled domes which required multiple helix angle wraps for their support, in place of the single kite-string wrap from pole to pole of the aluminum overwrapped design. The use of cold swaging of tube-ends to form bosses, demonstrated on subscale development efforts, had not been achieved full-scale when the contract was initiated. Difficulties arose with the full-scale demonstration which were not solvable at the time with the designs and equipment available. hence, an unanticipated development was the finally selected method of making the 4-in.-diameter stainless steel liner with a single boss and no welds in an 0.020-in.-thick wall, from an 0.050-in.-thick, 13-in.-diameter disk. The demonstration vessel failed by leakage during the prestressing step because embedded oxides had formed flaws in the boss region. Such flaws have been avoided by proper temperature control during hot spinning. Hence, a new design was developed which weighs half as much as its recently developed predecessor. Funds ran out before adequate testable hardware was produced.

Jan 1, 1983

By Mohamad Hussein

Low strain dynamic tests are performed to evaluate the structural integrity of driven or cast-in-place concrete piles. This type of testing requires minimal pile preparation, and is simply performed by attaching an accelerometer to the pile head and striking the pile head with a hand held hammer. The measured data is processed by a dedicated system, inspected for wave reflections, and interpreted based on one dimensional wave propagation theory. Piles are normally tested shortly after installation so that problems can be identified early and corrective measures taken before construction of the superstructure. However, evaluation of existing foundations is occasionally required. Often, pile installation records are not available rendering impossible any rational foundation reanalysis. This paper discusses three case histories where low strain dynamic measurements allowed determination of pile lengths and structural integrity under existing structures where pile heads were not accessible.

Jan 1, 1992

By Tracy Brettmann, Will Bohlen

An innovative retaining wall design consisting of tangent drilled shafts with supplementary seal piles was used to limit continuing bank erosion along the Brazos River in Southeast Texas. The riverbank erosion had progressed to where it was threatening the stability of both the bridge abutment and corresponding approach embankment of the heavily travelled Highway 99 bridge at this location. A tangent pile design was selected because it was both much faster to install and more cost effective than a secant pile system. The design included both 5.5-ft and 10-ft diameter shafts with depths up to 130-ft and comprised both anchored and cantilevered sections. Supplementary seal shafts were also installed between the structural tangent drilled shafts to help plug any gaps between the tangent shafts. The plumbness and diameter of the shafts were tested using a sonic caliper to make sure the shafts were installed within the specified tolerance. The initial design had to be revised when a record flood from Hurricane Harvey impacted the site during construction. Introduction The Fort Bend Grand Parkway Toll Road Authority (Owner) needed to protect the north bridge abutment with a retaining wall system due to rapidly eroding conditions of the Brazos River banks within the 300- feet-right-of-way of the State Highway 99 Jodie Stavinoha Bridge. The extent of the local scour and erosion along the north bank of the Brazos River has caused concern for the structural integrity of the bridge. The magnitude of the erosion along the north bank at the location of the bridge has been measured at about 120 feet over three recent hydrologic flood events locally referred to as Memorial Day 2015, Memorial Day 2016, and Tax Day 2016. During construction, a new record flood level occurred due to Hurricane Harvey in August of 2017 that resulted in a portion of the retaining wall needing to be redesigned due to even more erosion occurring. The Brazos River is an actively eroding and meandering alluvial river plain that naturally meanders and migrates over time. The processes of bank erosion and meander migration were ongoing before the bridge was constructed and will continue in the future. These recurring major flood events, however, rapidly increased the rate of erosion in just a few years. Background. Due to the need to protect the bridge as soon as possible, the Owner selected a project team consisting of the designer, general contractor and specialty deep foundation contractor prior to final design to work together in developing a cost-effective design that could be implemented rapidly. The project team initially considered both a secant pile and tangent pile retaining wall system using drilled shafts. After reviewing various alternative designs, a tangent pile wall with seal piles was selected based on both cost effectiveness and speed of installation. The tangent pile with seal pile option was approximately 20 percent lower in cost and 50 percent faster to install.

Jan 1, 2018

By Harold A. Watson

A method for measuring leakage of vapors into a chemical-cartridge half-mask facepiece during simulated use is described. The respirator, fitted with high efficiency cartridges, is worn in a dichlorodifluoromethane (CC12F2)--air test mixture while a series of timed activities (facial movements, varied breathing, exercise, etc.) is performed. Complementing other tightness tests, this method is useful particularly for studying face fit and the effect of facial movements on leakage. The concentration of CC12F2 within the facepiece is monitored continuously to observe the immediate effect of physical activity on leakage. A composite sample is collected simultaneously in a plastic bag as a measure of average leakage during the 18-minute test period. Leakage, reported as percent, is calculated from the concentrations of CC12F2 within the facepiece and in the test atmosphere.

Jan 1, 1970

By E. T. Dumble

THE first specimens of this material which came under my notice, as found in the State of Texas, were sent to me by Mr. J. C. Melcher, of Fayette county, soon after the organization of the State Geological Survey. I wrote him concerning it, and had the locality and manner of occurrence described, but 1 had no opportunity to visit and examine the deposit until the present field-season. Later, specimens were collected by Dr. Penrose and myself on a trip made by boat down the Rio Grande, from Eagle Pass to Hidalgo, in June, 1889. At the time of collection I marked the substance "Albertite," doubtfully, but, on examination, it proved to be nearer Grahamite. The geological horizon of the two occurrences is Tertiary. The first locality mentioned is in the upper part of the beds called by us Fayette beds, and provisionally correlated with the Miocene, or Grand Gulf of Hilgard's Mississippi section, while the latter is in the lowest strata of the Eocene which are exposed on the Rio

Jan 1, 1893

By J D. Goldsworthy

The McPhee Creek bedded iron deposit is a recent discovery made by Giralia Resources NL (Giralia) in the northern Pilbara of Western Australia. The deposit lies 30 km north of the town of Nullagine along the southeastern margin of the East Pilbara Granite-Greenstone Terrane (EPGGT).The McPhee Creek area is located in the Kelly Greenstone Belt in the southeastern part of the EPGGT. The Archaean aged greenstone belt consists of volcanic and sedimentary sequences including the Warrawoona Group and the Gorge Creek Group. The McPhee Creek iron ore deposit lies within banded iron formation (BIF) rocks of the Gorge Creek Group. The structure of the McPhee Creek area is dominated by a northeast trending, upright synform (Sandy Creek Syncline) and associated folding that is truncated by northeast trending faults in the east. Iron ore mineralisation is predominantly stratabound and follows the dip of the bedding – however, in some areas, particularly in the southwest of the deposit, mapped steep to moderate dips of bedding planes are at odds with underlying fl at mineralised zones in drill sections. Zones within the deposit that contain substantial thickness of iron ore correspond to areas of complex folding suggesting structural control and iron enrichment in fold hinges. Petrographic analyses confirm mineralisation is goethite dominant and the deposit is strongly supergene enriched.Giralia initially identified iron ore potential in the McPhee Creek area through the presence of a small known channel iron deposit (CID) mesa. Giralia began exploration in 2008 by re-drilling a portion of the CID (subsequently named Crescent Moon) and reported a small low-grade Inferred Mineral Resource. Target generation in the wider area utilising Geological Society of Western Australia maps and Ikonos satellite images identifi ed strongly ferruginous outcrops associated with major structures along an 8 km long range located 2.5 km to the west north-west of the Crescent Moon CID deposit. In late July 2008, a total of 62 rock chip samples were collected during a helicopter supported sampling program conducted at McPhee Creek. Samples taken from haematite-goethite enriched BIF and canga zones outcropping intermittently over the 8 km length of the western and central areas of the prominent range assayed up to 63 per cent Fe. These zones represent the discovery outcrops and surface expression of the McPhee Creek main range iron ore deposit.Follow up sampling, geological mapping, bulldozing of access tracks and ramps and reverse circulation (RC) drilling commenced in September 2009. A maiden Inferred Mineral Resource was announced by Giralia to the Australasian Securities Exchange (ASX) on 15 December 2009.The current Indicated and Inferred Mineral Resource at December 2010 stands at 260 Mt grading 56.2 per cent Fe, 0.12 per cent P, 6.7 per cent SiO2, 2.3 per cent Al2O3 and 9.5 per cent LOI at a 50 per cent Fe cut-off. McPhee Creek is one of the largest iron deposits found in Archaean BIF in the northern Pilbara.

Jul 11, 2011

By Gary E. Sherman

To aid the U.S. Army Corps of Engineers in their Resource Development Navigation Study, the U.S. Bureau of Mines (Bureau) examined the potential for mineral development near ten Alaska port sites. This report presents the results for the following four sites: Balboa Bay, Beluga, Lost River, and Point MacKenzie. There are 579 known deposits within the area considered for these ports. The majority of the deposits are located within a highway/railroad corridor examined for the Point MacKenzie port site. Based on the current level of knowledge, coal deposits near the Beluga and Point MacKenzie port sites are most likely to be developed in the near future. This conclusion is based on the fact that coal projects in these areas are actively being pursued for development. The mineral wealth surrounding the four port sites is substantial. Mine models were used to examine the potential for mining tin, gold, silver, copper, and molybdenum. The models were based on published reserve and grade data and therefore do not include proprietary company data which, if available, would likely change the analysis results. Of the models examined, the tin placer mine model developed for the Lost River port site proved to be closest to being economic.

Jan 1, 2011

By L. B. Phelps

A method is presented for the burial of potentially toxic spoil in high density zones or packages within spoil piles. Such burial could reduce the outflow of pollutants and thus minimize contamination of groundwater flows. Laboratory model studies using ammonium bromide tracer were performed to quantify the expected outflow mixing that could be achieved through package construction in spoils. Field drilling and geophysical density logging of spoils was carried out at three sites in Pennsylvania and Ohio to obtain a range of field spoil bulk density measurements and spoil samples. These data are analyzed to determine the relationships between spoil density and the controlling factors of lithology, depth, age, particle size distribution and mining method. A separate series of spoil permeability tests were performed in the laboratory to investigate the relationship between permeability and its related parameters. Research results are applied to the toxic package method to suggest guidelines for pack-age size, shape, density and placement for future field prototype development.

Jan 1, 1981

By G. Kleyn

"Sub-standard practices and their adverse impact on safety performance remain a challenge in the South African gold mining industry. The purpose of this study was to investigate the root causes of sub-standard practices and the effect on safety performance in South African gold mines. The focus of the study was on the underground production operations at a gold mine in the Free State. The study consisted of three parts: a personal investigation into the causes of sub-standard practices at the mine, a comparison with the results of a cultural study performed at the West Wits mines, and a behavioural survey.The studies described in this article yielded similar results in terms of the key drivers behind sub-standard practices. It was found that substandard practices had a number of causes, and the origin lies within the habits, attitude, and behaviour of employees. Current methods of addressing sub-standard practices and improving safety performance were found to discourage employees from performing work safely and according to procedure. It was concluded that the lack of critical behavioural habits for the given work environment and job title could possibly be the primary reason for the occurrence of sub-standard practices. IntroductionSince the implementation of the Mine Health and Safety Act, 1996 (Act 29 of 1996) and the Mine Health and Safety Regulations, the South African mining industry has been striving to improve health and safety performance and has placed great emphasis on adherence to mine standards.The Act requires employers in the mining industry to report accidents, incidents, and dangerous situations to the Regional Principal Inspector of Mines in their area. The data provided by employers is captured and analysed by the South African Mines Reportable Accident Statistical System (SAMRASS) and made available for public viewing (Department of Mineral Resources, 2011).A review of the national mine-related accident statistics shows clearly that the South African gold mining industry has improved its safety performance markedly over the past decade, but is still facing major challenges (Figure 1). These include meeting the Mine Health and Safety Milestones (Department of Mineral Resources, 2011)."

Jan 1, 2016

By F. -J. Wodopia

Sustainability of energy supplies has been an issue of general interest for a long time. Whilst in the past the continuous productive use of natural commodities was in the fore, its compatibility with the environment and climate and ultimately also social aspects have recently gained more and more attention. Today many discussions focus on the climate compatibility of individual options to act. Fossil fuels, in particular coal and lignite, are generally challenged because coal use makes a significant contribution to global man-made CO2 emissions. The drastic increase in the consumption of fossil fuels is not explained by the fact that coal utilisation technologies are not or cannot be sustainable but rather by the growing world population and the endeavours numerous national economies trying to catch up economically. Coal is the world’s No. 1 fuel and, in the view of many experts, will keep this position also in the foreseeable future. The access to its deposits plays a significant role for the economies of the emerging countries. Consequently the aspects of energy security and economic efficiency need to be considered at eye level with climate compatibility. In Germany, however, the public acceptance of fossil fuels and of large industrial projects is in the focus of attention.

Jan 1, 2011

By R. L. Kloberdanz

Peruvian legislation requires the preparation of an Environmental Impact Study (EIS) for new and expanding mines/beneficiation facilities and the preparation and implementation of an Environmental Adjustment and Management Program (PAMA) to control and mitigate environmental impacts associated with existing mining/beneficiation activities. Shepherd Miller, Inc., developed guidance documents for preparing an EIS and PAMA for Peru's Ministry of Energy and Mines and presented workshops to Peru's mining industry on preparing an EIS and PAMA. This paper discusses the process and approach taken and the results.

Jan 1, 1998

W. L. SaundeRs, New York City (communication to the Secretary*):—Notwithstanding the sweeping statements made by Mr. Clarke in this paper, the friends of compressed air are not dismayed. There is no war between electricity and compressed air. Each one has its field of usefulness, and in that field each is supreme. In spite of commercial interests, in spite of prejudices and the enthusiasm of the inventor, the thing that is best will survive and flourish. At least ten years ago, our engineering papers contained large advertisements and pages of reading-matter about the application of electricity to mines, recording the introduction of numerous rock-drilling plants, and claiming that the problem had been solved, greatly to the advantage of the miner and with promise of large profits to the manufacturers of electrical apparatus. Edison and Thomson labored to apply electricity to mines, and each believed that the probabilities of success were great. This was the period of the solelloid rock-drill, which mas admirably suited, theoretically, to the percussive principle and in the development of which hundreds of thousands of dollars have been spent without satisfactory result. I have searched in vain for a standard mining equipment where electric rock-drills are in constant, commercial operation. During a recent trip made from New York to California, I visited most of the important mines of the West and failed to discover a single electric equipment, so far as this class of mining-work is concerned. If any one will inform me where there exists today an electric-drilling equipment in constant service in mines in the United States, I shall be glad to receive the information. Mr. Clarke has been for some years an active and intelligent writer on the subject of electricity for mining. Whenever his

Jan 1, 1904

By E. A. Mihok

A pilot plant for treating mine drainage by neutralization with limestone was designed, fabricated, and operated by the Bureau of Mines. The process consists of (1) producing a very fine (minus 400-mesh) limestone slurry, (2) mixing the slurry with the mine water, (3) aerating the resulting mixture to remove carbon dioxide and precipitate iron, and (4) separating the solids from the liquid by sedimentation. A mine discharge of pH 2.8, containing 1,700 ppm total acidity, 36 ppm ferrous iron, and 360 ppm total iron, was treated at rates from 300 to 400 gpm. The treated water ultimately reached a pH of 7.4 and contained no detectable iron. The resulting sludge compacted to approximately one-third the volume of sludge from mine water neutralized with lime. The advantages of the limestone process, compared with the conventional lime process are as follows: Widespread distribution and lower cost of run-of-mine, indigenous limestone; simplicity of plant design; reduced hazards and plant operating and maintenance costs accruing from the use of a less reactive chemical agent; higher solids concentration of the precipitated sludge; and no deleterious effect caused by accidental overtreatment. While total process costs could not be determined, it is conservatively estimated that the cost of treating mine water by the limestone process is one-third to one-half the cost of the lime process, depending on the characteristics of the water to be treated and the availability and quality of limestone used.

Jan 1, 1968

By W. K. Gowans

The Sullivan Concentrator treats a complex sulphide ore consisting mainly of galena, marmatite and pyrrhotite. The ore carried minor values in silver, antimony, bismuth, indium and tin. The products of the concentrator are lead, zinc, iron and tin concentrates. The minor metal values other than tin are recovered from the concentrates by the refining processes in the smelter at Trail.The concentrator was completed in 1923 and first operated with a capacity of 2,500 tons per day. In the years 1926 to 1929 changes to equipment and buildings brought the operation up to 5,500 tons per day and then, in the years 1935 to 1945, the daily tonnage was raised to 8,500 tons. After 1945, the rising insoluble content of the ore made it necessary to consider the construction of a Sink-Float plant. At this time consideration was also given to the construction of a new crushing plant underground to replace the rolls crushers and cone crushers located at the concentrator. By 1949, construction of the Sink-Float plant was completed along with a new underground crushing plant, and an electric haulage way between the underground crushing chamber and the Sink-Float plant. The ore was hauled in forty 14-ton car trains which discharged into a 3,000 ton receiving bin by means of an air operated five car rotary dumper. With the start up of the,Sink-Float plant, a 1 ½ ft. by 12 ft. Hardinge rod mill was also brought into operation. The Sink-Float plant made it possible to treat 12,000 tons/day of mine run ore with up to 40% of this being rejected as float.

Jan 1, 1975

This paper reviews rehabilitation, closure, and post-closure management of the Tui, Golden Cross, and Martha Mines, all of which are located in the Waikato Region of New Zealand. There was no requirement for rehabilitation of the Tui mine, which was abandoned in 1973. There was a requirement to rehabilitate the Golden Cross mine. Mining at that site ceased in 1997, and rehabilitation is now well advanced. When first approved, there were some requirements for rehabilitation of the Martha Mine, but when reconsented in 1998, those were extended, and in addition a requirement for post-closure management was included. As a result, a Trust, funded by the mining company, has been established to take long-term responsibility for the site following completion of closure. The different rehabilitation/closure requirements at each of these sites illustrates that we have learnt something from the experiences of the past.

Jan 1, 2003