Search Documents

By Emil-Paul Lorenz

Considered as a whole, the mineral resources of the Turkish Republic (Anatolia) are in their untapped virgin state, and the little development shown is not the result of modern systematic geologic exploration but the continuation of the ancient open-pit mining methods of the Orient. When I came to Turkey in 1924, I found myself confronted by a formidable task because of the lack of preliminary geologic mapping. Today this condition has not essentially changed; less than one per cent of the country is covered by topographic mapping adequate for modern requirements. However, I was able to bring a semblance of order in a presentation of the mineral deposits of this country, by tracing the story of the mineral deposits that showed surface evidence of their existence. At present only the easily discovered mineral deposits of coal, copper, and lead-silver ores are being exploited. In the case of coal, of 3,000,000,000 metric tons available, only 100,000,000 have been mined. The same is also true for copper, lead-silver, and other ores, as shown in Table 1.

Jan 1, 1948

By Cyril Stanley Smith

ARCHEOLOGISTS, by use of the terms Bronze Age and Iron Age, indicate that metals have in the past determined the character of civilization. The relatively simple discovery by a primitive metallurgist that the addition of tin to copper both facilitated the production of castings and increased the durability of the product enabled hunter, warrior, and housewife alike to do things never dreamed of before. Similarly, the smelting of iron and the discovery of hardening methods greatly changed the arts of peace and war. Discoveries of low-melting-point alloys for joining and for making household utensils, and perhaps the adornment of a feminine form by sparkling precious-metal jewelry, have at times changed the destiny of a country. Bronze cannon, the cast and wrought iron Watt engine, copper transmission lines, and aluminum alloy aircraft, are cases of particular metals making possible the realization of an improved engineering design. Perhaps of the greatest influence of all upon civilization was the development of type metal. The rapid increase in the rate of dissemination of knowledge dates from the day that the technique of the pewterer was utilized in making rapidly reproducible and accurately sized letters for printing. It was not movable type, but metal type that was important, for metal castings could be made of identically the same shape and size at an enormous rate, and possessed excellent inking and wearing characteristics.

Jan 1, 1946

By Michael Oakland

This paper will discuss the design analysis of sheet pile cofferdams for static and dynamic blast loads. Following construction of the new Willis Avenue Bridge across the East River between Brooklyn and Manhattan, in-river piers No. 9 and No. 10 from the former bridge were demolished, partially by explosive charges. The blast at Pier 10 was conducted first and though the demolition charge was relatively small, it gave confidence that the sheeting could be designed to resist the blast load. This paper primarily summarizes our analysis and performance of a sheet pile cofferdam at Pier 9 used to withstand the larger blast loads, contain the blast debris, and allow excavation of the pier below the existing river bed mudline. The program NLFlex was used to predict stresses and deformations of the cofferdams under dynamic blast loads, using simplified equations to estimate the underwater blast pressures. Specifically, the analysis focused on the stresses in the struts, waler beam, sheet pile interlocks and connection of the sheeting to the waler beam. Design included allowing plastic deformations and limited rupture of the sheet pile interlocks under the blast loading. Comparisons are made between stresses assessed by the dynamic finite element modeling and empirical relationships used within the industry. The performance of the system after the actual blast is discussed as well as details of the performance of welded vs. bolted connections within the system.

By Bruno Vingiani, Alessandro Bertero

"The use of Artificial Ground Freezing (AGF) for temporary soil strengthening and seepage control is an effective alternative to grouting when dealing with soils whose degree of finesses would imply the use of highly expensive chemical grouts. However, compared to grouting, the application of this improvement technique usually needs a more accurate preliminary soil investigation campaign and a design assisted by specific calculation software. Besides a general description of the main features of this technique, the paper will describe a recent application of AGF carried out in Rome to underpass an existing metro station.INTRODUCTIONNatural ground freezing occurs seasonally or permanently (permafrost) in some areas of the globe close to the poles and can negatively affect the engineering performance of underground structures. On the other hand, Artificial Ground Freezing (AGF) is man-made controllable freezing process that can be used in foundation engineering to temporarily strengthen the ground and create a barrier to the passage of groundwater. During the process, the heat is extracted from the soil in a cylindrical shape around a number of freezing pipes installed into the ground. This action produces columns of frozen soil, which expand gradually till they merge and create continuous frozen wall. The thickness of this barrier can be regulated according to the specific project requirements. Nowadays, AGF technique is applied to a wide range of foundation engineering problems where soil stability and groundwater flows are an issue (Pimentel et al. 2011, Haß and Schäfers, 2013). Typical applications include the temporary stabilization and waterproof of the ground around the excavation profile of mined tunnels until the construction of the final lining (Figure 1).The case history described in this paper deals with a recent application of AGF carried out during the construction of metro Line “C” in Rome. Specifically, this technique has been applied to allow the construction of two single-track mined tunnels running underneath an existing metro station belonging to Line “A”. In that case, the AGF has been evaluated by the Designers as the only possible solution for improving the mechanical and hydraulic characteristics"

Jan 1, 1900

By Samuel S. Wyer

THE installation of the gas-producer power-plant in America has been so unusual that all engineers have viewed it with in¬terest; a large majority, however, regard it with a lack of con-fidence and many with positive distrust. Despite the fact that European engineers have usually been less inclined to take the initiative along experimental lines than are Americans, they have, nevertheless, developed the gas-producer plant to a very high state of efficiency to which they were forced by the neces¬sity of economy in fuel-consumption. The gas-producer power-plant is so common in Europe that engineers as well as the general public regard it with the same degree of confidence that is now universally placed in steam¬plants. Gas-engines, both small and large, are in general use there, and central stations, aggregating several thousand horse¬power, are quite numerous. The fact that gas-producer power-plants have received so little attention in America may be attributed to five conditions:-1', ignorance and prejudice; 2, newness of work; 3, in-

Mar 1, 1905

By George C. Stone

AS most of you probably know, Australia has had many strikes. The two places that had the worst reputation were the Broken Hill mines and Port Pirie, where the smelter was located. About four or five years ago, the smelter changed hands. The new proprietors - immediately endeavored to get on better terms with the men and made such progress in that respect that, the men came to them and said, "There is no use giving us any more money. You have just raised our pay one- bob a day, but the store-keeper and the boarding-house keeper have raised their prices. The boarding housekeeper raised our board three bob a week and the storekeeper took the rest of it and we are no better off." Learning that what the men needed most was firewood wood the company bought the wood on a tract of ground across Spencer's Gulf and- sent men over to cut it. The wood was brought to the works and given to a man to cut up. He thought he had an easy job and loafed, but when the committee representing the men discovered that his loafing added to the cost of 'the wood, it promptly disciplined him and made -him work as he had never worked before. The next question that arose was the distribution of the wood. The committee got bids from several cartmen whose prices varied from about two to five shillings. It gave the work to the next to the lowest bidder. The fact that if delivering the wood cost more, the user would have to pay for it, was an entirely new idea to the men.

Jan 1, 1920

By B. E. Field

COBALT is a silvery white metal with a slight bluish cast, strongly resembling nickel in its appearance and properties, notably its resistance to corrosion, although its alloys with other metals differ quite decidedly in their properties from those of nickel. The name cobalt was derived from the German "Kobold" meaning goblin and this came to be applied to the cobalt minerals which, although they resembled ores, did not readily yield metal when smelted by the primitive processes available in the Middle Ages. Cobalt minerals were used as pigments by potters and glass workers before the Christian era. Cobalt blue glass was found in the tombs of the Egyptians and in the ruins of Troy, and many colors used by the ancient Greeks and Romans contained cobalt. The ancients were entirely unaware that the colors they used were caused by cobalt and the metal itself was only isolated about the middle of the eighteenth century by Brandt although the preparation of cobalt compounds had been carried on in a small way ever since the opening of the silver-cobalt deposits at Schneeberg, Germany, in 1470. The metal is fairly hard, with a density when pure of 8.81 in the cast state and 8.92 after working. The com¬mercial grade of cobalt has a density of about 8.75 in the cast state. The atomic weight is 58.97. The Brinell hardness of the pure metal is 124; that of the commercial grade varies from as low as 100 to as high as 138, depending upon the impurities present. Pure cobalt has a sharp melting point at 1478°C. The tensile strength of the pure metal in the cast condition is said to be higher than that of any other pure metal. Kalmus gives it as 34,400 lb. per sq. in. for cast unannealed metal; the effect of annealing at 850 to 900°C. is to raise the strength slightly. The yield point is close to the ultimate strength and the reduction in area and elongation are both low. Mechanical working raises the tensile strength of pure cobalt rapidly and in the form of wire it will be over 100,000 lb. per sq. in. The presence of small quantities of carbon in the commercial metal raises the tensile strength to as high as 61,000 lb. per sq. in., the reduction in area and elongation being raised at the same time to approximately 20 per cent.

Jan 1, 1933

By John M. Lovejoy

NATURAL resources become a source of wealth as they are exploited and made available to the people in usable form. Experience has taught us that Nature does not readily give up her treasures, but the ingenuity of man in the field of techologic progress is required to find and efficiently exploit these resources. History has also demonstrated that with advancing technologic knowledge the. world has become progressively richer in its resources. Those that could not be commercially exploited are now being turned to beneficial use. Through expanding technology and the use of substitutes and synthetics, availability of the world's sources of natural wealth is today many times that of a hundred or a thousand years ago. And so it is with petroleum. Technology is also the great multiplier of our petroleum resources. Through improvements in the art of finding, drilling, and producing, our ability to meet rapidly increasing demands over the last quarter century has been maintained. On the other hand, had our

Jan 1, 1944

By H. O. Hofman

(Canal Zone Meeting, November, 19]0.) THE sudden decease, April 1, 1910, in Chicago, of Dr. Franklin R. Carpenter was a shock to his- many friends. He died in his sixty-second year, of heart paralysis. To most fellow-members of the Institute who have followed the progress of the. last twenty-five years in the mining and treatment of non-ferrous ores, the work of Dr. Carpenter in that line is familiar ; but very few, even of those who knew him well in the later years, are acquainted with his earlier struggles to satisfy an inborn hunger for knowledge. The story of his life resembles that of the pioneer who opens up new country; overcoming hardships with indomitable courage, meeting doubts and difficulties with an alert and open mind, and exercising in the face of reverses an unconquerable perseverance. It seems appropriate to place on record in the Transactions a brief outline of the life and work of this eminent engineer. During the past 15 years of his life Dr. Carpenter was much interested in genealogy. In the pursuit of this study as an avocation, he traced his own ancestry to the time when ?Hugh," called "le Charpentier" on account of the dexterity with which he had swung his battle-axe as a crusader, settled in Sussex on lands received from William the Conqueror. The Carpenters came to this country with William Penn. A prominent member of the family was Joshua Carpenter, the founder of Christ Church, Philadelphia. Dr. Carpenter's branch of -the family moved from Pennsylvania into that part of Virginia which is now West Virginia, where his grandfather settled in Harrison county, while the grand-uncle went further west, and built the first iron-furnace at Hanging Rock, Lawrence county, Ohio. In fact, since early times, the Carpenters appear to have been iron-masters. Franklin R.. Carpenter was born, Nov. 5, 1848, in Parkers-

Aug 1, 1910

By HOWARND N. EAVENSON

THE year 1930 resembled the preceding one in the coal industry in continuing the era of falling prices and 'of the abandonment of unprofitable mines. Practically all coal prices fell, and in the steam sizes during the last half of the year this was particularly true, due to the small industrial demand. No new mines of any size were opened in the bituminous coal industry, but there was a steady increase in the number of cleaning plants of all kinds built in all fields. It is estimated that at least nine million tons per year were added to the previous total of washed coal. The largest washing plant started during the year was that of the Buckeye Coal Co., at Nemacolin, Pa., with a capacity of 650 tons per hour. Fig. 1 shows - the mixing-bin, conveyor galleries, washing-plant and skip hoist, and Fig. 2 the 120-ft. Dorr thickener for collecting the 48-mesh material from the wash water. Dryers are used for drying the steam coal product. The following statement by J. R. Campbell shows the effect of cleaning on Pittsburgh coal in Greene County: "With the advent of the 650-t.p.h. efficient washing plant in Greene County at the Nemacolin mine of the Buckeye Coal Co., it has undoubtedly been demonstrated that the potential coking-metallurgical coals of the county can be brought within the pale of the highest grade high-volatile coals for steel manufacture. A few months' operation indicates that 9% per cent ash in the raw coal can be easily reduced to under 7 per cent ash in the washed coal and the sulfur from 1.60 per cent in the run of mine to 1.20 per cent sulfur in the washed coal.

Jan 1, 1931

By Robert Linton

M ETHODS by which Americanization is developed among the foreign workers at the mines in the United States, with particular reference to mines of the Pennsylvania coal region, were discussed in a most constructive way at the Wilkes-Barre Meeting of the Institute. Arthur Notman, of the Phelps Dodge Corpn., as chairman, guided the discussion. Americanization was defined by E. E. Bach, !chairman of the Institute's Sub-committee on Americanization, who said: "Americanization applies either to the native-born or foreign-born and is that process of assimilation which guarantees the full functioning of American citizenship. Naturalization papers merely entitle one to the privileges of citizenship."

Jan 1, 1921

By D. S. Sanders

IN the four mills of the Cerro de Pasco Copper Corp. in Peru, some 3000 tons of complex sulphide ores are treated daily, with four kinds of concentrates produced: copper, lead, zinc, and pyrite, each containing values in silver, gold, bismuth, and some other metals. Copper occurs in the various ores as chalcopyrite, enargite, tetrahedrite, tenantite, bournonite, and chalcocite; lead as galena; and zinc as sphalerite and marmatite. Small amounts of silver and tungsten minerals are also present. The gangue consist mainly of shale, quartzite, calcite, rhodochrosite, pyrite, and pyrrhotite. In general the values are freed with a relatively coarse grind, about 70 prr cent minus 200 mesh being the finest to which the pulps are ground. In Morococha and Casapalca however. sphalerite particles much finer than this contain inclusions of chalcopyrit r. At Cerro de Pasco the silver and gold are present in all sizes of the ground pyrite.

Jan 1, 1945

By Paul M. Tyler

THE winning of metals from Nature has been advanced to a degree of efficiency that commands admiration even in this Machine Age. Economy of human effort underground, in surface plants, and in treatment works, and better means of performing all manner of operations have cut costs and im¬proved products to an extent that seems far beyond the wildest imagin¬ings of those that labored in the days of hand mining and muscular metallurgy. Principles and methods borrowed from other professions and sciences - mechanical engineering, chemistry, and physics-all have con¬tributed to the rapid development of ore production and treatment, but no small part of the achievements must be credited to the free exchange of ideas within the industry itself and mass attack upon problems of mutual concern. The esprit de corps or class consciousness that has contributed so effectively to the progress of the metal industries has been less apparent among nonmetallic mineral producers. As a class they have been handicapped by inadequate contact with the metal-mining fraternity as well as among themselves.

Jan 1, 1935

By Partha Sircar

"For Berth 22 modifications at the Port of Oakland, nearly 600 octagonal 24-inch ‘diameter’ precast-prestressed concrete piles were driven, some piles over 160 feet long. Prior to production pile driving, an indicator/test pile program was performed, which included extensive use of dynamic load testing with (Pile Driving Analyzer (PDA) & CAPWAP analyses. The indicator test-pile program resulted in requiring significantly longer piles than the original design based on subsurface borings. The cause of this discrepancy is investigated in light of the available geotechnical information, soil mechanics principles and standard techniques for pile capacity computations. Several interesting phenomena emerged. These include relatively low resistances offered by crushed rockfill than would conventionally be assumed, non-homogeneity of an apparently uniform formation and the effects of jetting on pile side friction. Also revealing was the significant increase in capacity between 1 and 3 weeks of driving for long piles in clay. Recommendations were developed for pile capacity for future use as “lessons learned”.IntroductionThe foundation for the replaced Berth 22 structure at the Port of Oakland in California involved driving approximately 570, 24-inch octagonal precast prestressed concrete piles. A plan and a section for the pile locations are presented in Figure 1.The ultimate loads on the piles used in the design are presented in Table 1 – the loads are quite heavy.The foundation design was followed by an extensive Indicator Pile Program. The contractors (Manson Construction Co. of Richmond, California) opted to use a Delmag D62-02 diesel hammer (Rated Maximum Energy – 165 kip-feet). Per the project specifications, the same hammer was used for both indicator and production pile driving. The production piles of appropriate lengths were ordered based on thr results of the Indicator Pile Program. A number of interesting results were found from the Indicator Program, which is discussed in this paper."

Jan 1, 2015

By AIME AIME

OVER-ALL operations of the oil industry, as measured by production of crude oil and consumption of products, are almost exactly of the same magnitude as a year ago. Does this mean that the great oil industry has been undisturbed by the war? Has this industry, so vital to the prosecution of the war and to the maintenance of our way of life, been unaffected in its operations? No indeed - changes within the industry are great. It has been called upon to revamp its trans¬portation methods so as to move about one fourth of the total amount of crude and refined products by railroad tank car instead of by ocean-going tankers. Its fundamental internal economy, based on maximum gasoline yield from a barrel of crude, has been relegated to memories of the past. Rationing of oil products, which has been forced upon us in face of an abundant supply, is not only disagreeable medicine but is in itself completely disruptive to the marketing end of the-business.-

Jan 1, 1942

By Georgc E. Collins

SEVERAL years ago, I estimated the total stock of gold in the world to be about a thousand million ounces, of which rather over one-third was available for monetary uses. Robert H. Ridgway has estimated the world's production from 1493 to 1927 as slightly over this amount. Of this total, 1.5 per cent was produced between 1493 and 1850 (before the Californian and Australian goldfields began to flood the world with gold), 331/2 per cent from 1851 to 1900, and 511/2 per cent from 1900 to 1927. Allowing for loss by attrition and permanent consumption in the arts, and for loss of buried treas¬ure, my first-mentioned estimate is perhaps not far from the truth; but my estimate of the monetary stock was certainly too low. Of the total production stated by Rid-way. 28 per cent came from North America. 26.9 per cent from Africa, 1.6.8 per cent from Australasia, 12.4 per cent from South America, and 11.2 per cent from Asia. Excepting that from the African conglomerate beds, the ultimate origin of which is still the subject of controversy, by far the greater part of the total production was derived from alluvials. Weighing all contingencies, it is improbable that any such production as has been made during the last forty years will be repeated in any similar period, if the present price level is maintained. The gold standard today seems firmly established except for temporary digressions. Nevertheless, no well-informed mining engineer will venture to assert the probability that the material for its maintenance throughout future generations can be furnished.

Jan 1, 1932

By AIME AIME

PRACTICALLY all the Section delegates as well as a sprinkling of Institute officers and mere members were on hand for the annual business meeting of the Institute on Monday afternoon of the Annual Meeting. President McAuliffe presided, with C. H. Mathewson as associate chairman. Americo Albala was first called on to discuss the work of the Pan American Institute of Mining Engineering and Geology. C. Will Wright said that the need for such an organization was evident, and a resolution was passed asking the incoming President to appoint a committee to investigate cooperation with that body, of which Mr. Albala is executive secretary.

Jan 1, 1943

By John Mould, Gordon Chen, Michael Oakland, William McElwee

"This paper will discuss the design analysis of sheet pile cofferdams for static and dynamic blast loads. Following construction of the new Willis Avenue Bridge across the East River between Brooklyn and Manhattan, in-river piers No. 9 and No. 10 from the former bridge were demolished, partially by explosive charges. The blast at Pier 10 was conducted first and though the demolition charge was relatively small, it gave confidence that the sheeting could be designed to resist the blast load. This paper primarily summarizes our analysis and performance of a sheet pile cofferdam at Pier 9 used to withstand the larger blast loads, contain the blast debris, and allow excavation of the pier below the existing river bed mudline. The program NLFlex was used to predict stresses and deformations of the cofferdams under dynamic blast loads, using simplified equations to estimate the underwater blast pressures. Specifically, the analysis focused on the stresses in the struts, waler beam, sheet pile interlocks and connection of the sheeting to the waler beam. Design included allowing plastic deformations and limited rupture of the sheet pile interlocks under the blast loading. Comparisons are made between stresses assessed by the dynamic finite element modeling and empirical relationships used within the industry. The performance of the system after the actual blast is discussed as well as details of the performance of welded vs. bolted connections within the system. IntroductionThe Willis Avenue Bridge is one of the major access ways from the Bronx into Manhattan. The location is shown on Figure 1. The original bridge constructed in 1901 was a swing bridge over the East River. The bridge was in disrepair and outdated with regards to its ability to handle the flow of traffic resulting in numerousaccidents.In 2007, Kiewit Constructors Inc./Weeks Marine, Inc., A Joint Venture was selected to construct a replacement bridge. The $612 million project included construction of a new bridge just to the south of the original bridge. The most notable aspect of the construction was floating and lifting the new 350 ft. long swing span in place as a single piece. However, another significant challenge was using blasting to demolish two of the abandoned piers which were within the East River. The blast would be near existing structures in both Manhattan and Brooklyn and would be within 30 ft. of the new bridge."

Jan 1, 2017

By Courtenay de Kalb

THE Exposed Treasure gold-mine has, for the past four years, been one of the largest producing mines of Southern California, its annual output having constituted 1 per cent of the total gold and silver production of the entire State. At the present moment the property is idle, owing to the large quantity of water encountered oil the lower levels, which will require the installation of a powerful pumping-plant before operations can be recommenced. Moreover, a prompt change in the character of the ore has occurred at water-level, which makes imperative an extensive campaign of development in the region of the unoxidized ores before a plant adapted to their treatment can be definitely decided upon. The character of the changes encountered in these deeper ores makes the geology of this deposit a matter of importance, not only for the immediate district, but for the desert region of Southern California in general, where many mines exist having in the oxidized belt conditions that, in many respects, resemble those in the Exposed Treasure mine. The deposit is situated in an apparently isolated butte about 2.5 miles south from the town of Mojave, on the Mojave desert; The butte, though apparently isolated, is in fact geologically part of an extinct volcano, known as Soledad butte, which rises out of the plain 1,5 miles SW. of the mine, to an altitude of 4,650 ft. above sea-level. Other buttes also rise from the desert plain toward the south and east, and again to the westward, all being closely related geologically to Soledad butte,-the whole constituting a single system as to origin and time. Since the end of the period of active volcanism in this region, there has been extensive denudation, the ancient plateau having been dissected during an epoch of apparently exces-

Jan 1, 1907

By H. LIVINGSTONE LMAN

A GOOD DEAL of information concerning flotation has come out during the patent litigation of recent years, and the legal situation has cleared considerably, to the satisfaction of Minerals Separation, Limited. Hence, Mr. H. Livingstone Sulman, one of the originators of the successful process of that company, felt at liberty to explain, on Thursday, Nov. 20, his experience and his views in a "Contribution to the Study of Flotation," before the Institution of Mining and Metallurgy. He did not give technical details. He dealt with the physical problems, so simple, as he remarked, that he had wanted 96 pages to express his views. He presented much data, partly new and based on observations of his own, bearing upon the very complex flotation phenomena in an instructive wav and made frequent references to the valuable researches especially of Prof. Edwin Edser and Mr. Emil Hatschek.

Jan 1, 1920