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By Thiann R. Yu, William J. Quesnel

At Kidd Creek, the annual production of 4.5 million tonnes of ore has been achieved primarily with sublevel blasthole stoping. This mining method has allowed underground operations to meet the designed production capacity while maintaining an outstanding safety record. To achieve this goal, rock mechanics principles have been integrated into each facet of mining in the planning stage, in the production stage, and in various stages of ground support. This paper evaluates the two adopted mining sequences based on ground stress patterns, blasting control, ground reinforcement, backfill support, and numerical modelling for stope stability at the mines.

Jan 1, 1984

Background The annual awards, which have been given by the US National Committee for Rock Mechanics since its inception in 1969, recognize out- standing research in rock mechanics. Such recognition has always been accompanied by a plaque or certificate for the winners and a presentation at the symposium awards banquet. Starting this year, the US National Committee will give the winners even more recognition and allow the rock mechanics community to benefit from the papers by publishing abstracts of the work in the proceedings of the 25th US Symposium on Rock Mechanics and in various society journals and news letters. "We hope this will stimulate the production of more research papers," said William R. Judd, former chairman on the subpanel of awards. "It's beneficial for researchers to have their work published as an award paper." There are four categories of awards: Basic Research, Applied Research, Case History, and Student Masters' Thesis. Approximately ten papers are nominated annually for each category; however, in some years awards are not made in all four categories. For instance, there were not enough case history nominations in 1983 for an award, but there were two equally outstanding recipients of the award for applied research. The winners of the 1983 research awards reflect the wide variety of professions involved with rock mechanics. They are introduced on the following pages by category, and accompanied by an abstract of the paper

Jan 1, 1984

THE first session of the Institute was held at the Smithsonian Institution, on Tuesday evening, February 22d. The members were welcomed to Washington and to the Smithsonian by Prof. Joseph Henry. President Holley responded to the cordial welcome of Professor Henry, and then read an introductory address on the subject of Technical Education. Following the discussion on President Holley's address the following persons, duly proposed and indorsed by the Council, were elected members and associates of the Institute : MEMBERS. Emile R. Abadie, - St. Louis, Ma. R. J. Anderson, - Pittsburgh, Pa. Commander L. A. Beardslee, - Washington, D. C. Charles Bender, - New York City. Channing M. Bolton, - Richmond, Va. Thomas E. Bowman, - Silverton, Colorado. Calvin E. Brodhead, - Bethlehem, Pa. M. L. Brosius, - Lewistown, Pa. Harvey H. Brown, - Cleveland, Ohio. James A. Burden, - Troy, N. Y. J. P. Clemes, - Sonora, Mexico. N. H. Cone, - Nederland, Colorado. W. F. Durfee, - New York City. Robert Frazer, Jr., - Ashland, Pa. Joseph E. Galigher, - Bingham, Utah. William Golding, - Steel Works P. O., Pa. Samuel E. Griscom, - Pottsville, Pa. Gen. E. Burd Grubb, - Beverly, N. J. Arthur R. Guerard, - Charleston, S. C. Edward Hart, - Easton, Pa. Prof. Lewis M. Haupt, - Philadelphia. . R. S. Hawley, - Buffalo, N.Y. John W. Hoffman, - Philadelphia. Nelson P. Hulst, - Milwaukee, Wis. H. C. Humphrey, - Philadelphia. Ed. P. Jennings, - Ithaca, N. Y. B. F. Jones, - Pittsburgh, Pa.

Jan 1, 1876

By Sir Nathaniel Barnaby

We must not conceal from ourselves that, against the perils arising from perforation of the shells or hulls of ships, we are greatly worse off in these days of steel and iron than we were when our ships were built of oak, teak and pine. Apart from the greater

Jan 1, 1891

By Forbes Wilson

IN February 1952 Freeport Sulphur Company started exploration work on a group of lateritic deposits at Moa Bay, Cuba. As a result of successful exploration work and a vast amount of metallurgical research over the past five years, these deposits will soon become a new Free World source of nickel and cobalt. Moa Bay lies on the north coast of Oriente Province, the easternmost part of the island, about 600 miles east of Havana and about 40 miles east of the U. S. Government nickel plant at Nicaro.

Jan 5, 1958

By W. A. Hockings, G. W. Lower, K. A. Smith

The kinetics of dissolution of metallic copper in aqueous cupric ammonium carbonate solutions were investigated. The major variables studied were temperature, agitation, and the cupric, cuprous, ammonia and carbonate concentrations. The rates of copper dissolution from rotating discs were determined by measuring the weight loss. The dissolution rate increased with the square root of the disc rpm and doubled when the temperature was increased from 20°c to 40°C.

Jan 1, 1973

By Fred W. Gordon

The heading of this paper was prompted by the knowledge that experience, up to this time, seemed to indicate that smaller furnaces were preferable for smelting the material of this section. Since the reasonable success thus far achieved by the first furnace of this plant tends to change the above opinion, and unsettle the generally-accepted views of furnace-men as to "weak " coke, a few words as to the design of the plant and the mode of operation adopted may prove interesting.

Jan 1, 1889

By K. J. Miller, R. E. Hucko

The Coal Reparation Division of the Pittsburgh Mining Technology Center conducted an investigation to assess and compare the pyritic sulfur reduction potential of coal-pyrite flotation and high-gradient magnetic separation (HGMS). Tests were run on three coals - an Upper Freeport bed coal, a Lower Kittanning bed coal, and a Pittsburgh bed coal - to establish grade-recovery relationships characteristic of both processes. Representative portions of each coal sample were crushed to two top sizes-nominal - 500 pm (-35 mesh) and nominal - 149 pm (-100 mesh)-and subjected to conventional froth flotation. The froth product was then beneficiated by coal- pyrite flotation or HGMS, to provide a direct technical companion of the two processes. At - 500 pm (- 35 mesh), the size normally employed for coal flotation, both coal-pyrite flotation and HGMS effectively separated pyrite from coal, and the performance of the two processes was essentially the same. At a - 149 pm (- 100 mesh) sire, however, the performance of HGMS exceeded that of coal-pyrite flotation. The separation effected by HGMS were more efficient at - 149 pm (- 100 mesh) than at - 500 pm (- 35 mesh). On the other hand, it was concluded that either the effectiveness of coal-pyrite flotation decreases with diminishing top size or the process has not been optimized to treat material finer than 500 pm (35 mesh).

Jan 1, 1983

By H. D. Dahl, Roger C. Parsons

In order to improve roof stability, Continental Oil Co.'s research program, initiated in 1969, was directed toward defining the geological parameters that affect the severity of roof conditions in any particular area of the mine. In addition, the program was seeking to define why roof falls in the Humphrey No. 7 mine (and in northern West Virginia-southwestern Pennsylvania coal mining areas) are oriented so that they occur primarily in north-south rooms or entries. Conclusions and recommendations from this study of roof fall orientation are given.

Jan 1, 1973

Jan 1, 1954

By W. R. Ingalls

MANY years ago, I expressed the opinion, in writings and otherwise, that it was possible to desulfurize zinc blende autogenously, i.e., without the use of extraneous fuel, and that at some time this would be accomplished. This opinion was based on thermal calculations and also on observations of the behavior of blende during roasting in different ways, all of which observations tended to confirm the theoretical calculations. Among such observations were things like the following: Once in carrying out the stall roast of cupriferous pyrites as a regular metal-lurgical operation, I was minded to charge a stall with lump blende, ranging from walnut to egg size, as I recollect, following the same procedure as with pyrites, and setting fire to the kindling wood, observe what would happen. The blende charge ignited well enough and bravely began to burn, quite actively the first day, at a diminished rate the second day, while on the third day burning ceased and the charge quickly became cold. It was just like trying to set a grate full of anthracite afire with insufficient kindling wood. The volume of air drawn through the stall was too great, quickly cooling the entire contents below the ignition temperature, which means, of course, that burning ceased.

Jan 12, 1922

Copper from Central Africa was well known to the Arab slave traders who depredated the country in the nineteenth century. By the 1870's slave raiding was so intense that the habits of the tribes were disrupted, and they no longer worked the copper deposits or made the crosses and bars of copper which had been their custom. In fact, the country had been greatly depopulated by the slave raiders. News of this horror was spread to the civilized world by missionaries and, in particular, by David Livingstone's writings. Whether to extend geographic knowledge, to suppress slavery or for national aggrandizement, the rush for African territory was on at the end of the nineteenth century. Cecil Rhodes at this time was established by his successes in diamonds and gold. He obtained the blessing of Lord Salisbury in 1889 to form the British South Africa Company under crown charter. His objectives were to occupy the lands north of the Zambezi for England and pay for development out of the country's mineral deposits. He planned to occupy the territory and close the gap to form an all-British route from the Cape to Cairo, one of his great dreams. With this master plan in mind he sent his agents into the field to make treaties with the tribes.

Jan 12, 1962

By I. Iwasaki, R. H. Heerema

The presence of calcium and magnesium ions in iron ore pulps that are upgraded by selective desliming can result in indiscriminate flocculation of both iron oxide and siliceous gangue slimes. The removal of these alkaline earth cations in pulp solutions by chemical precipitation was ineffective as a means of deflocculation of quartz. It was shown by using various techniques (electron micrographs, abstraction, and streaming potential measurements, and cationic flotation tests) that heterocoagulation between the precipitates [Mg(OH)2, hydroxyapatite, and CaCO3] and quartz particles was the reason behind that observation. In addition, the precipitates adversely affected the recovery of quartz by cationic flotation, due to slime coating, a case of heterocoagulation. Magnesium hydroxide produced a uniform layer of coating across the quartz surface, while hydroxyapatite and calcite produced discrete, localized deposits dotting the surface.

Jan 1, 1981

By Byron Pickard

AT MIDNIGHT of Sunday, Aug. 27, 1922, a fire was discovered in the main shaft of the Argonaut mine, Jackson, Cal. With the excep-tion of a shift boss and two skip tenders who escaped, the entire night shift of 47 men was trapped in the mine and entombed for 22 days, when the bodies were recovered. The entombed miners made a valiant but fruitless effort to save their lives. Rescue crews toiled strenu-ously day and night for 21 days to save the entombed men, only to find they had arrived too late. From the experiences of the entombed miners and of the rescue crews, valuable lessons may be learned to prevent future catastrophes.

Jan 11, 1922

NEW MEMBERS The following list comprises the names of those persons who became members during the period Apr. 10, 1919, to May 10, 1919. BEAVER, JAMES J., Supt., Mech. Ore Loaders, Tennessee Coal, Iron & R.R. Co., Box 62, Bessemer, Ala. BLACKWELDER, ELIOT Geol. & Prof. of Geol., Univ. of Ill., Urbana, Ill. BRAECKE, GUSTAVE E., -Min. Engr., Mgr., Societe Curas et Soldado, La Carolina, Spain. BRINK, CYRIL GORDON, Reduction Officer, Charge of Reduction Works. Fairview Devonian Montrose Gold Mines, Ltd., P. O. Sheba, Transvaal, So. Africa. COMERFORD, JOSEPH S., Chief Chem. & Met., American Manganese Steel Co., New Castle, Delaware. DROSDOWSKI, N. C. V., Asst. Supt.,, The Spassky Copper Mine, Ltd., Karagandy, Akmolinsk, Oblast, Siberia. DUNGLINSON, GEORGE, JR., Asst. to Gen'l Mgr., Norfolk & Western Railroad, Bluefield, W. Va. FARAGHER, PAUL VANCE, Research Fellow on Light Metals, Mellon Institute, Pittsburgh, Pa.

Jan 6, 1919

By S. F. Shaw

Fox some time it has been more or less recognized within the industry that a scientific control of flowing wells would result in increased production and a greater ultimate recovery of oil. About two years ago it was proposed by the writer that this control should follow principles worked out by him while handling large air-life operations. In the case of wells that had ceased to flow where a large quantity of liquid was present, the use of these principles would result in a large increase of production by using compressed air or gas to flow the well; in the case of a well flowing naturally it would take the form of controlling the gas associated with the oil, resulting either in immediate increase of production or in a reduction of the gas consumed per barrel of oil, and in both cases would result in a greater ultimate recovery from the sand. The Roxana Petroleum Corp., appreciating the advantages to be obtained by a scientific application of the principles of the air lift to oil wells, recently engaged, for a limited time, the services of the writer to work out some of the problems involved. The work was carried out at Braman, Garber and Tonkawa in Oklahoma, and at Oxford in Kansas. Following some suggestions of the writer a well was also equipped by the Roxana company at Smackover by A. S. Field.

Jan 11, 1926

By Richard B. Greenwalt, John M. Bertram, George E. Aiken

Agglomeration developments in the iron ore industry of North America over the past twenty years are closely related to shifting patterns in commercially acceptable ore grades and even the definition of iron ores. As early as WW II the rich Mesabi hematites were depleted, ending a 50-year era of direct shipping ores that included reserves of an estimated three billion tons. Decreasing ore grades and rising costs began to force the closing of many underground iron mines and processes were being developed to use domestic low-grade iron deposits. This resulted in the rapid development of iron ore beneficiation processes and signaled the coming trend toward concentration, sintering and pelletizing. Yet even today when agglomeration facilities are treating 90 % of the Mesabi Range product much remains to be done in keeping world-wide competitive forces in check and in ensuring the long- term utilization of these expansive ore supplies in an up-until-now captive U.S. market.

Jan 10, 1973

By G. R. Green, R. C. McDonald

I n 1966 a major expansion program in Canada was undertaken by Inco to meet increasing nickel requirements. Coinciding as it did with a severe labor shortage, a large portion of this expanded production had to be accomplished through increasing productivity in tons per man-shift in every phase of the operation. In the mining section of the company the first step to this end was the adoption of load-haul-dump equipment for ore removal. Concurrent with the expanding use of this equipment, a program to improve drilling and breaking efficiency was also undertaken. The first drilling machine added in the program was 3-boom unit capable of drilling a complete cut-and-fill bench 28 ft wide, and 10 ft high with 12 ft horizontal holes from a single setup. Using one-pass steel, one operator could drill the complete face with- out leaving the controls except to change bits. The unit was mounted on a 4-wheeled, rubber-tired chassis powered by a 66-hp air-cooled Deutz diesel motor. When in position it was connected to min

Jan 6, 1972

By D. J. Dunn, J. L. Huiatt, T. E. Norman

Corrosion studies in laboratory ball mills and grinding environment simulations produce corrision rates and total metal removal rates much lower than those recorded in operating production ball mills. The corrosion component of ball metal loss in many mills probably represents less than 10% of the total loss, judging from AMAX experience and recent US Bureau of Mines (USBM) tests. Such small absolute losses are consistent with ball metal loss measured in production ball mill marked ball wear tests to determine effects of corrosion and abrasion resisting properties of alloys in operating mills. These indicate that metal hardness and microstructure determine relative metal loss rates of a given situation. The combination of ore characteristics and grinding process dynamics determine metal loss severity. Alloying for corrosion resistance and modification of the milling corrosion environment yield relatively small metal loss reductions. Alloying and heat treatment to produce high hardness and microstructures of high carbon martensite and, for cast irons M7C3 carbides, produces the lowest metal losses in typical wet grinding applications.

Jan 1, 1986

By John B. Goddard, David R. Brosnahan

Leaching of uranium in situ from sandstone deposits with ammonium carbonate solution containing dissolved oxygen occurs rapidly compared with the leaching of the bulk of the sulfur present as FeS2. However, because of their high reducing capacity and their relative abundance, the FeS2 minerals consume the bulk of the oxidant. A pressure leach apparatus was constructed that permitted measuring oxygen consumption by FeS2, best described by a first-order reaction. The experimental rate constants for various cores are roughly proportional to their FeS2 contents.

Jan 1, 1983