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By Paul Morrison

The paper describes the design process, trial testing and contract pile installation of 772 pre­cast concrete piles at a site in Surrey, South East England. Recommendations on how to improve the design, construction trials and main contract piling phases of the project are made. The building layout is shown in Figure 1 and is comprised of a central circulation area with five office wings radiating out from its southern side (only three of these wings were constructed in Phase 1 of the project). Approximately 60% of the circulation area and one office wing were built with a single level basement. The basement was constructed "bottom-up" in open cut with the void between the basement walls and the cut slope being back-filled with compacted site won soil above a perimeter drainage system at basement slab level. The building has up to 3 stories above basement level and is a reinforced concrete structure. The client for the project is Pfizer Ltd. Pfizer Ltd was represented on site by Laing Project Management (Laing). The consulting engineer was Ove Arup and Partners (Arup) while the piling contractor was Roger Bullivant Ltd (RBL).

Jan 1, 2000

By Charles W. Frey

COMPRESSED air is one of the most useful tools that the mine operator has at his disposal. It is clean, nontoxic, easily handled, and can be distributed anywhere that a man can drag a length of rubber hose. Without it a great deal of drilling would still be a laborious hand process, and although the John Henry of legendary fame could beat a mechanical drill, John Henrys are few and far between, and in the long run the air drill is the victor. As a general rule, horizontal compressors are lubricated by mechanical lubricators, which furnish oil to the cylinder walls, whereas vertical units are splash lubricated. In most horizontal machines oil is introduced at the top center of the piston, from which point it can run down and lubricate the rest of the piston. Some large units introduce oil at more than one point on the cylinder wall, the necessity for this and the number of points of introduction depending upon the size of the cylinder.

Jan 1, 1938

Ground-water and tailings pond monitoring in the Upper Santa Cruz Basin Mines Task Force's Special Studies Area has been performed to determine the nature and extent of aquifer contamination from copper tailings pond's recharge in the basin. A monitoring program for each of three mining areas (Mines A, B, and D) was developed. Analysis of data shows that recharge from Mine A's ponds has caused increased hardness, sulfate and total dissolved solids in local ground water. However, pumpage in the area has controlled most of the water's movement. Pond recharge from Mine B has led to similar conditions, and the degraded water is moving towards a local public-supply well. Pumpage from Mine D's interceptor wells is controlling some, but not all, of the movement of recharge seepage from Mine D's ponds. Recommendations include the need for enhanced monitoring programs at each current mine site, development of a monitoring program for Mine C's area, development of water budgets for all mines, investigation of tailings pond compaction and sliming, establishment of mine closure plans for containment of recharged pond water, and the need for additional interceptor wells in several locations.

Jan 1, 1983

By M. F. Goudge

ROCK wool, one of the most recent additions to the list of Canadian-made, insulating materials, is a soft, light, fibrous material consisting of interlaced, flexible, glassy fibres so exceedingly fine that, individually, they are almost invisible to the naked eye and will float in air. In the process of manufacture, a suitable rock, generally a self-fluxing argillaceous dolomite consisting of nearly equal proportions of acidic and basic constituents, is melted to a completely fluid state and then converted into fibres either by a blast of steam or air, or by a mechanical device. The increase within the past five years in the number of plants in the United States making rock wool and slag wool has been remarkable, especially in view of the depressed conditions prevailing 'with most industries during this period. In 1930, there were only 8 plants reporting production of .these materials, whereas at the present time there are 44 plants in the United States listed as making these products, and there are 3 plants in Canada. In 1929, the total sales of rock-wool products in the United States amounted to-$2,377,324. In 1934, according to the National Rock and Slag Wool Association, 26 member companies reported sales of $3,695,405, and in 1935 the sale's of 30 member companies had a value of $5,571,469. The establishment of the rock-wool industry in Canada followed the publication in 1931 of a report (1) by the Mines Branch, Department of Mines, Ottawa, in which was set forth the results of field work and laboratory studies which indicated that large deposits of rock in the Niagara peninsula, hitherto regarded as valueless, were suitable for the making of rock wool. This report was supplemented in 1934 by another report (2), giving the results of further laboratory and commercial-scale tests on the rock from these particular deposits, which proved conclusively that rock wool of good quality could be made from the rock in question.

Jan 1, 1936

By D M. Brady

Underground coal mines in Australia have embraced the use of various inertisation techniques both proactively and reactively. The use of such techniques can have a significant influence on ratios and trends used to monitor the status of the underground environment. Whilst control strategies should never be ignored in favour of preserving the integrity of ratios, the influence and significance of the changes likely to be seen should be anticipated and understood for reliable interpretation of the situation. This paper looks at the influence inertisation techniques can have on results and subsequent interpretation.CITATION:Brady, D M, 2013. The influence of inertisation techniques on gas interpretation, in Proceedings The Australian Mine Ventilation Conference , pp 259-264 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 1, 2013

By J. S. Carman

As with the slogans of Madison Avenue, catch words or phrases frequently become topical. Much is heard these days of the confrontation between governments of developing countries and international mining capital. In actual fact, sadly there are too few cases of anything as positive as confrontation because such an action at least signifies a dialogue which may begin badly but end up fruitfully. Instead we have in general a climate of indifference and fear with the mining companies of note marking off most of the developing world as being unsafe for investment. There is an unreal air to this damaging impasse. The common sense and objectivity which are prerequisites of positive action are lost in a swirling cloud of mythology, embraced largely by governments. Let us examine some of the dangerous misconceptions.

Jan 1, 1977

By George R. Elliott

Introduction The pages that follow present a brief chronological survey of views which have been held, and of legislation enacted, for the regulation of the natural gas and oil industry in the Turner Valley field, especially as regards conservation of the natural gas. To provide a necessary background for an adequate understanding of the progress of events in western Canada, there is included also a compilation, from technical and legal authorities, of some of the more important measures which have been adopted for the regulation of the oil and gas fields of the United States, where these measures have had, or are likely to have, a bearing on the course of our domestic industry. Owing to exigencies of space, it has been possible to refer only to the most outstanding proposals and legislation, and to these in the briefest possible form. Although, so far as Canada is concerned, the data presented are restricted almost entirely to the Turner Valley field, it is the hope of the writer that the paper may prove of value for purposes of reference: for any similar gas and oil fields discovered in western Canada will certainly revive and intensify the problem of the proper steps to be taken for the conservation of the gas. Definition of 'Conservation The term conservation has been so misunderstood and misrepresented that, to many persons in Alberta, it means little more than closing-in wells. In the light of the definition of Charles E. Hughes, that 'True conservation of a raw material is its economical use', the subject of natural gas conservation is inseparably involved with the study of the function of the -gas and with the development of the principles of unit operation.

Jan 1, 1934

By M. R. Campbell

"IntroductionON THE LAST DAY of December, 1951, a half-century of steel production was completed in the open hearth department of Dominion Iron & Steel, Limited, in Sydney, Nova Scotia.During that period, almost every known variation of basic steel making practice was used in working out a steel making process which would overcome the difficult metallurgical problems imposed by the use of Cape Breton coal and Wabana ore.This paper is presented as a brief review of these steel making practices, setting forth the fundamental metallurgical factors involved in their success or failure.Establishing the IndustryThe story of steel production at Sydney is closely interwoven with that of coal. The steel industry owes its inception to a desire on the part of the Dominion Coal Company, which was incorporated in 1893, to improve its marketing position by increasing sales of slack coal and providing a year-round demand for its product. Accordingly, the Dominion Iron and Steel Company, Limited, was incorporated on March 30th, 1899, with Mr. H. M. Whitney -who was President of the Dominion Coal Company -as its first President. The new Company was given powers to manufacture and process iron and steel, and to mine all minerals, including coal.A strong inducement to the industry was the bounty offered by the Dominion Government for the production of both iron and steel."

Jan 1, 1952

By K. J. Ashley

Over the last six years I have been involved with the calculation of ore reserves and mine planning using various computer systems and soft- ware packages. This experience has given me a unique perspective from which to view the needs of the engineers and geologists whose job it is to produce geologic and mineable ore reserves. The purpose of this paper is to share that perspective with those who are in this field or are thinking of purchasing computer software to aid in these calculations. My first experience with computers in mining was the creation of a mini-computer based coal reserve and mine planning package written as part of my Easter's thesis. This package took about ten weeks to write, four weeks to document, and two weeks to install at the mine for which it was written. It did what it was designed to do, which was to emulate the hand procedure which had been used prior to its installation. The package was specific to its application which involved several small seams of coal being mined simultaneously and would have required major modification for it to be applied to a mine where, say, one thick seam was mined in two benches.

Jan 1, 1985

By Vhutali Carol Madanda, FHATUWANI SENGANI, François Mulenga

The first introduction of fuzzy theory in the nineteenth century created room for continuous research and application in various fields. Fuzzy set theory has been globally applied in geotechnical engineering, and research in this field continues to date. The fuzzy inference system is considered to be one of the most popular techniques adopted to resolve some of the geomechanical challenges faced in both surface and underground excavations. This paper unpacks fuzzy theory-based approaches in mine geomechanics with the aim of expanding the innovative application of the same approach specifically in tunnel geomechanics. This aim was achieved by conducting a review of recent successful and unsuccessful applications of fuzzy inference systems in underground excavations/tunnelling geomechanics. Indeed, this review has outlined some cardinal points associated with the ability of the technique to solve complex geomechanics problems. However, the success of the technique was accompanied by a few limitations associated with the methodology. Finally, a future outlook associated with the technique has been established.

May 15, 2023

"THE CONCEPT of energy as a commodity, while not entirely new, is not as widespread as the importance of the idea to this modern world would lead one to expect. The growth in the supply and use of energy over the past years has been tremendous, but our very closeness and familiarity have somewhat distorted the viewpoint, particularly of the younger generation. To many of us who remember the wonderful satisfaction of our first responsibility for directing two horsepower hitched to a farm cart or hay wagon, there still arises a feeling of some awe at the casual flick of the switch with which our sons and daughters summon to their convenience the service of some one hundred or more horsepower.Energy is the vital component of our existence and, no matter what contempt our day-to-day familiarity may •breed, it is wise to .pause from time to time and consider our national energy standing. Have we still capital in the bank? Are our expenditures wisely •conceived and well directed? Is provision being made for the years •ahead for the needs of our children and our children's children?"

Jan 1, 1953

By J. -M. Bosgiraud, G. Armand, S. Dewonck, L. Richard-Panot

"The Meuse/Haute-Marne Underground Research Laboratory (URL) is located on the eastern boundary of the Paris Basin. The URL started to be built in 2000 (shaft sinking operations) in the framework of ANDRA’s (French national radioactive waste management agency) research program aimed at determining the feasibility of a reversible deep geological disposal of high-level and intermediate-level long-lived radioactive waste (HLW, IL-LLW). Its underground drifts are used to study the Callovo- Oxfordian claystone layer between 420 m and 550 m in depth.The ongoing research program (started in 2006) following the “Technology Readiness Level” (TRL) Scale is more dedicated to technologies improvement and demonstration issue of the different disposal components, even if characterization and monitoring studies are still ongoing.In rock mechanics, at the main level of the URL (located at 490 m), construction and evolution of disposal cells of different size are studied for HLW and IL-LLW packages. A step by step approach, started in 2006, is carried out based on comparison of HM behavior of parallel drifts excavated/supported by different construction methods. These various configurations give insight of the influence of construction method on the EDZ extent and evolution and on the progressive loading of the support, which are key issues to design the Cigéo disposal drifts and excavations.The concept of disposal cells studied for HLW consists in horizontal steel lined micro-tunnels 80 m long and 70 cm in diameter. Several campaigns of tests have been carried out since 2009 in order to demonstrate the feasibility of excavating such micro-tunnels and study their behavior under different conditions (with and without back filling the annular gap between the rock and the casing, watertight or not casing). A full scale demonstrator representative of the benchmark concept has also been excavated, to study its behaviour under thermal loading with heat produced by electrical heaters."

Jan 1, 2015

By Walter Knox, Charles H. Sawyer

All of the coals commonly used in domestic bituminous stokers form coke, and satisfactory operation depends upon the fact that the coke formed is so weakly bound together that it breaks readily in the normal operation of the stoker and automatically maintains a good fuel bed. Some coals, because of their tendency to form solid, blocky coke, are practically excluded from use in small domestic stokers as now built. Other coals, some among the best stoker coals available, can form this troublesome coke under certain conditions. Many contradictory methods have been offered as cures for coke formation. Generally the procedure has been to try various adjustments until a combination was found that seemed to give better results. Such random methods of treatment have not provided any reliable information as to causes. The present paper covers a comprehensive test program undertaken by the Koppers Company's Stoker Coal Research Laboratory at Kearny, N. J. The program had two main objectives; first, to discover what factors affected coke formation, and second; to define corrective steps that could be applied in stoker service work. Conclusions and Results i. The design of the stoker outweighs in importance all other factors capable of improving coke formation. 2. Insufficient air supply aggravates the formation of large blocky coke, although raising the air above 30 to 40 per cent excess (as determined during steady running) does not further improve the character of the coke formed and only reduces its accumulation at the expense of efficiency, increased fly ash, poorer clinker-ing, and other disadvantages. 3. Increasing the coal feed results in a somewhat more friable coke structure and is recommended for persistently troublesome jobs. 4. Increasing over-fire draft improves the character of the coke formed and reduces troublesome accumulations by accelerating off-period burning, although at some expense in efficiency and some increase in fly-ash accumulation. 5. Coke structure was not substantially improved by blocking some of 'the retort tuyeres, although the blocking of tuyeres at the feed-screw end of a rectangular retort did lead to somewhat improved performance, possibly because of considerably better distribution of coke in the fuel bed. 6. With the equipment tested no difference was shown between installation of the same stoker in a steam boiler and a warm-air furnace, or between a sand-filled and a ventilated type of hearth. 7. The following design features had no noticeable effect on coke formation: a. Presence or absence of coal-tube air as provided by many manufacturers to eliminate smoke-back. B. Presence or absence of a flap damper ill the air duct to minimize off-period burning. c. Continuous or intermittent (ratchet and pawl driven) movement of fuel feed screw.

Jan 1, 1944

By Charles H. Sawyer, Walter Knox

All of the coals commonly used in domestic bituminous stokers form coke, and satisfactory operation depends upon the fact that the coke formed is so weakly bound together that it breaks readily in the normal operation of the stoker and automatically maintains a good fuel bed. Some coals, because of their tendency to form solid, blocky coke, are practically excluded from use in small domestic stokers as now built. Other coals, some among the best stoker coals available, can form this troublesome coke under certain conditions. Many contradictory methods have been offered as cures for coke formation. Generally the procedure has been to try various adjustments until a combination was found that seemed to give better results. Such random methods of treatment have not provided any reliable information as to causes. The present paper covers a comprehensive test program undertaken by the Koppers Company's Stoker Coal Research Laboratory at Kearny, N. J. The program had two main objectives; first, to discover what factors affected coke formation, and second; to define corrective steps that could be applied in stoker service work. Conclusions and Results i. The design of the stoker outweighs in importance all other factors capable of improving coke formation. 2. Insufficient air supply aggravates the formation of large blocky coke, although raising the air above 30 to 40 per cent excess (as determined during steady running) does not further improve the character of the coke formed and only reduces its accumulation at the expense of efficiency, increased fly ash, poorer clinker-ing, and other disadvantages. 3. Increasing the coal feed results in a somewhat more friable coke structure and is recommended for persistently troublesome jobs. 4. Increasing over-fire draft improves the character of the coke formed and reduces troublesome accumulations by accelerating off-period burning, although at some expense in efficiency and some increase in fly-ash accumulation. 5. Coke structure was not substantially improved by blocking some of 'the retort tuyeres, although the blocking of tuyeres at the feed-screw end of a rectangular retort did lead to somewhat improved performance, possibly because of considerably better distribution of coke in the fuel bed. 6. With the equipment tested no difference was shown between installation of the same stoker in a steam boiler and a warm-air furnace, or between a sand-filled and a ventilated type of hearth. 7. The following design features had no noticeable effect on coke formation: a. Presence or absence of coal-tube air as provided by many manufacturers to eliminate smoke-back. B. Presence or absence of a flap damper ill the air duct to minimize off-period burning. c. Continuous or intermittent (ratchet and pawl driven) movement of fuel feed screw.

Jan 1, 1944

By Robert W. Ageton

The Bureau of Mines investigated the in situ vertical component of the rock stress in the rib of the haulage drift on the 6100-level of the Star mine, Burke, Idaho, using the flatjack and borehole deformation methods. The estimate of the vertical component of stress about 2 feet into the rib at a station along the haulage drift on the 6100-level of the Star mine by the flatjack method is approximately 5,875 psi, whereas the borehole deformation procedure at this station yielded a value of 5,500 psi for the same depth into the rib. The test zone is approximately 5,625 feet below the surface.No attempt was made to extrapolate stress estimates beyond the depth of the flatjack installation.

Jan 1, 1967

By Paul M. Tyler

Graphite is an essential war mineral and for that reason has received much attention from the standpoint of national defense. During the World War the situation with respect to graphite supplies, though it never became acute, caused considerable concern. Even in peace time, however, graphite has aroused more interest than the actual size of the industry seems to warrant. Despite this wide interest the facts of the industry do not seem to be generally known. Often there has been an almost total disregard of the essential' economic and technical problems involved. Long ago Bastin3 made the following statement; in a Government' report: "To-day there are more abandoned mines and mills in the United States than the number in operation * * *. In the number of times' some of these properties have changed hands in the course of a few years, there is a record of misrepresentation and disappointment that can hardly be equaled in any other branch of mining; and many properties have been notoriously associated with stock manipulation of doubtful character." According to one authority fully 600 graphite mines have failed in the United States, and the record shows that of all these properties scarcely a score have ever succeeded in operating for as much as a year or two. More than 40 mines have been worked at various times in the State of New York alone and at least that many in Alabama. Throughout the country, in fact, there are scarcely a dozen States in which efforts have not been made at some time to exploit graphite deposits. At the present time the list of mines that can be classed as at all active is reduced to less than ten. Failures inevitably occur in all lands of mining, but the disheartening feature of the record of graphite mining in this country is that so few ventures have even paid back the money put into them and. that none has been a conspicuous success.

Jan 1, 1929

By E. M. Wise

THOUGH known as the platinum-group metal- the sextuplet, platinum, palladium, iridium. rhodium, osmium, ruthenium, might well be called the American metals or perhaps Pan-American metals, as the ore containing them eras first discovered in South America, and in recent years the largest production has come from North America. The South American alluvial deposits, which also, contain gold, are in active production, as are the alluvial platinum deposits of Alaska, but the main production is from the copper-nickel ores of Sudbury, Ontario. The Russian deposits in the Urals were the source of most of the worlds platinum for about 100 years, but since 1934 have assumed second place. For a time considerable amounts of platinum came from several rather rich deposits in South Africa but these were exhausted quickly. However, a tremendous reserve of lower-grade ore exists there, which could be worked profitably if the price of platinum were considerably higher.

Jan 1, 1942

By Joseph Gersic

In 1989-90, the Bureau of Mines appraised selected high resource potential areas containing gold, rare-earth-element, or pegmatite deposits in or near the Black Hills National Forest. Available mineral resource data were used to construct mine and mill models and to compute discounted cash-flow rate-of-return analyses. Using this information, the economic feasibility of possible operations and probability (in the nonmathematical sense) of exploration and development within the next decade were assessed. High exploration and development probabilities are forecast for gold deposits around existing and permitted mine areas near Lead-Deadwood and west of Galena. The area east of Galena has low to moderate exploration and development probability; the Rochford area has low to high exploration probability and low to moderate development probability; the Keystone area has low to moderate exploration probability and low development probability; the Medicine Mountain area has moderate to high exploration and low to moderate development probabilities. Exploration probability in the Bear Lodge Mountains area is high for rare-earth elements and gold; development probability is low. Exploration probability for gold in the Mineral Hill area is low to moderate; development probability is low. The current level of activity associated with pegmatite mining in the Black Hills would probably not change significantly in the next decade; both exploration and development probabilities are low to moderate.

Jan 1, 1990

By E. Siami-Irdemoosa, S. R. Dindarloo

"Pareto analysis was used to investigate the failures database of a Hitachi EX1900 hydraulic shovel over one year of continuous operation. The hydraulic system and hydraulic links, hoses and piping were identified as the most critical system and subsystem, respectively. A three-parameter gamma distribution function was identified as the best fit for a probabilistic modeling of the time between failures (TBFs). This distribution was used in a Monte Carlo reliability analysis of the hydraulic system. Autoregressive integrated moving average (ARIMA), within the context of a time series analysis of the TBFs, was proposed as a viable alternative to the traditional technique of distribution fitting. The mean absolute percentage error (MAPE) metric was used to compare the two models. The MAPE value that resulted from the ARIMA was 66 percent smaller than that from the traditional technique in predicting the TBFs.Resumen ¦ Se usó análisis Pareto para investigar la base de datos de fallas de una pala hidráulica Hitachi EX1900 durante un periodo de un año de operación continua. Se identificó al sistema hidráulico y a los enlaces hidráulicos, mangueras y tuberías como el sistema y subsistema más importantes, respectivamente. Se identificó una función de distribución de tres parámetros gamma como el más apto para un modelado de probabilidades del tiempo transcurrido entre las fallas (Tabes por sus siglas en inglés). Esta distribución fue usada en un análisis de confiabilidad Monte Carlo para un sistema hidráulico. El promedio de movimiento integrado auto-regresivo (ARIMA por sus siglas en inglés), dentro del contexto de análisis de serie temporal de los TBFs, fue propuesto como una alternativa viable a la tradicional técnica de ajuste de distribución. Se usó el porcentaje de la media absoluta de error (MAPE) para comparar los dos modelos. El valor MAPE que resultó de la ARIMA fue 66 por ciento menor que el resultado obtenido con la técnica tradicional de predicción de TBFs."

Jan 1, 2015

By David Schlain

IN 1942 the Bureau of Mines began to develop the Kroll process for use in the large-scale production of titanium. Titanium and titanium alloys are now commercial metals. These metals are relatively expensive, but It is now evident that they will have important industrial uses and that in many instances these will be related to their remarkable corrosion resistance. This bulletin presents the known corrosion properties of titanium and its alloys in useful form. In marine environments titanium is highly resistant to corrosion and does not pit, or undergo crevice corrosion, stress corrosion, or corrosion fatigue. Titanium is also highly resistant in many salt solutions, including most chlorides. It is very resistant to corrosion in nitric acid solutions. It is also resistant to white fuming nitric acid. However, it may react violently with red fuming nitric acid. In phosphoric acid solutions titanium has rela¬tively good resistance to corrosion, but it has less resistance to sulfuric acid and still less to hydrochloric acid solutions. Titanium corrodes very rapidly in hydrofluoric acid Solutions. It is very resistant to corrosion in many organic chemicals. However, it has only moderate resistance to formic acid solutions and poor resistance inn oxalic acid solutions. Titanium does not corrode in dichloroaretic acid but, corrodes rapidly in 100 percent trichloroacetic acid at 100° C. Titanium is resistant to barium, calcium, magnesium, ammonium, and sodium hydroxides. Titanium is inert in wet chlorine, bromine, or iodine gases. However, in dry chlorine gas titanium reacts rapidly enough to ignite. It also reacts rapidly with dry bromine gas, but, it is resistant to dry iodine gas. When titanium is exposed to red fuming nitric acid solutions with high nitrogen dioxide content and low water content, it corrodes, undergoes stress-corrosion cracking, and becomes pyrophoric. This occurs more readily with some titanium alleys, such as titanium-8 percent manganese. A fresh titanium surface immersed in water or in an aqueous solution and in contact with an oxygen-rich atmosphere under sufficientt pressure is unstable and will ignite spontaneously. Inherently an active metal, titanium has a tendency to become less active in environments containing oxidizing agents such as air, oxygen, chlorine, or ferric, cupric, or platinic ions. Titanium is more noble than most structural metals in roost, environments and its excellent corrosion resistance is generally not, affected by contact with these metals. However, some of the other metals corrode faster because of contact with titanium. Titanium undergoes anodic polarization readily, so that even when it is the less noble member of a galvanic couple it may corrode less because of the contact. Titanium alloys often have corrosion properties and electrochemical characteristics similar to those of commercially pure titanium. Titanium alloys containing noble metals, zirconium, molybdenum, vanadium, tantalum, or copper sometimes have better corrosion resistance than pure titanium.

Jan 1, 1964