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By E. J. MCOAUSTLAND

THE behavior of steel after overstrain and at moderate temperatures is fairly well known. It has been made the subject of much investigation, and our knowledge is clear and definite on many points. The ultimate raising of the elastic limit, after moderate overstrain, and the consequent lowering of the ductility, seem to be well established. It is also well understood that the immediate effect of overstrain is to lower the elastic limit, possibly to zero, but that if not interfered with, this limit will subsequently rise higher than before. The "tests after moderate temperature," reported in this paper, were undertaken to verify the above statements for the particular steel under investigation, and also to determine, if possible, the total time required for complete recovery from this state of overstrain. The behavior of overstrained steel at temperatures at or below 32° F. is not so well known. Tests made by Prof E. G. Coker, at McGill University,' show that steel, overstrained and subjected to cold, will remain in a state of overstrain for an indefinite period. I am not aware of any other published results of tests along this particular line. The effect of time and temperature on the recovery of steel from overstrain was made in 1902-3 the subject of sortie investigation in the laboratories of the College of Civil Engineering of Cornell University. A general plan was outlined in connection with the regular courses of instruction in testing of materials; but the press of routine work and the demands of the schedules on the time of the students were so great as to presage long delay in the completion of the work. Not much had been accomplished up to 1904-05, when Messrs. E. C.

May 1, 1906

By E. Henderson, L. K. Daneshmend

Drawpoint control is critical in determining the cutoff point for load-haul-dump mucking operations to minimize dilution. It is also necessary to ensure even mucking distribution and to prevent possible hang-up of material within a stope. A prototype production monitoring and reporting system has been developed for load-haul-dump operations in under-ground mines. The system generates accurate and timely information regarding mucked tonnages and drawpoint and ore/waste pass utilization. The monitoring system integrates a PLC-based load weighing system with a radio frequency identification (RFID) system for locating the vehicle. The system records the identification and time of entry and exit of each draw-point and ore/waste pass visited during a shift, as well as the weight of each bucket load. A trial of the system was conducted at the CAN-MET Experimental Mine near Val d’Or, Quebec. The monitoring and reporting system functioned as designed, with the exception that the maximum read range of the RFID tags under dynamic conditions was found to be a limitation. RFID systems with greater range capabilities have been identified for a second generation system. The system is the first of its type in North America to demonstrate that RFID tagscan be successfully applied to locate trackless underground equipment. Because of their ability to locate equipment and personnel within underground mines, RFID systems should be considered a key technology for future mine information and process control systems.

Jan 1, 1996

By Mostafa Benzaazoua, Mariam El Adnani, My Ahmed Boumehdi, Rachid Hakkou, Salah Ouhamdouch, Abdelmalek Goumih

This study focuses on the environmental characterization and assessment of long-term neutral mine drainage (CND) potential from waste rock piles at the abandoned Erdouz mine in Morocco. The study involved metallographic analysis, static tests, and column tests. Results indicate that the waste rock is not an acid mine drainage generator but produces CND, mainly with sulfates exceeding Moroccan standards. The waste rock is relatively stable and could be reused after pretreatment.

Jan 25, 2022

By P. Duran

The metallurgical gas handling system at Chagres Smelter, like that of many smelters, can be the limiting constraint to processing more concentrate through the smelter. Mass and energy balances for the metallurgical gas handling system processing off-gases from the flash furnace and Peirce-Smith converters have been used by both operations and process engineering groups to help evaluate different operational scenarios in which the use of the installed capacity could be maximized and/or an operational strategy can be change with the purpose of removing a bottleneck or justifying an investment to relieve a constraint in the gas handling system. The present work describes the development of these process balances that were carried out in Exce®. The results were validated with operational data and, subsequently, some cases of industrial interest were simulated, detecting some conditions that were limiting the operation due to the present installed capacity in the Chagres Smelter.

Jan 1, 2007

Geostatistics originated as an application of a classical statistical concept, multivariate linear regression, to the solution of a practical problem, estimation of reserves in the South African gold mines. In this respect, geostatistics should only be considered as one statistical method among many that can be used to evaluate mineral deposits. R.F. Shurtz has studied possible applications of power spectrum analysis to the same problem, and these studies may result in future improvements over the presently accepted geostatistical methodology. The intention of R.F. Shurtz's paper, as stated by the author, is to "relate geostatistical doctrine to classical statistical and mathematical concepts." However, in this comparison the "geostatistical doctrine" appears to include only the simplest among the geostatistical concepts advocated by G. Matheron, while "classical statistical and mathematical concepts" are limited nearly exclusively to power spectrum analysis. The author attempts to compare the two methods, and to prove the theoretical superiority of power spectrum analysis. Unfortunately, a number of errors and incorrect statements are made concerning both the theory and application of geostatistics, which invalidate the comparison and the conclusions drawn from it. The errors made in this comparison are understandable since few scientists can claim to have expertise in two theories as diverse as those compared here. In many respects, this paper is reminiscent of polemics which occurred 15 to 20 years ago when geostatistics and trend surface analysis were compared. Each method has its own merit and limitations, and none can claim absolute superiority. The most misleading statements found in R.F. Shurtz's paper are: The definition of the semivariogram given on page 1923 is incorrect. If the maximum difference between two assays is 1, the maximum value of the semivariogram is not 1, as stated, but 0.5. The comparison of geostatistics and linear regression made in the section entitled "Insufficiency of Classical Statistics?" is not valid. The semivariogram of the sample values given in Table 1 (page 1919) has a parabolic shape indicative of a linear drift. When such a semivariogram is observed, the simplest method of geostatistical estimation (linear kriging with unknown mean) is not applicable. Universal kriging must be used that takes trends into account. On page 1921 it is stated that the use of trends "is officially disparaged in geostatistics." Again on page 1924 mention is made to "Matheron's commitment to random process (intrinsic) models and his present categorical rejection of deterministic (trend) models for mineral deposit evaluation." Indeed, from articles published by geostatisticians in the 1960s one could infer that geostatistical methods are not compatible with the presence of trends. However, even the simplest

Jan 1, 1984

University of Alabama University, Alabama Mining and Metallurgical Society JOSEPH CHARLES MEAD, President WAYNE G. BRIGGS, Secretary J. R. CUDWORTH, Faculty Sponsor RICHARD L. BOWRON, Counselor University of Arizona Tucson, Arizona Miners' Society W. JAMES THOMAS, President LAMONT WEST, Secretary J. B. CUNNINGHAM, Faculty Sponsor B. R. HATCHER, Counselor

Jan 1, 1938

Mining Methods GERALD F. SHERMAN, Chairman JOHN A. CHURCH, Vice-chaiman CHARLES W. WRIGHT, Secretary Alluvial Mining CLINTON BERNARD CHARLES JANIN H.R. NORSWORTHY Open-cut Mining Iron MAX H. BARBER J. A. MACKILLICAN Copper MICHAEL CURLEY R.B. TEMPEST Underground Mining Iron C. H. BAXTER TENNEY C. DESOLLAR

Jan 1, 1934

Extractive Metallurgy Division Institute of Metals Division Iron and Steel Division OFFICERS AND COMMITTEES W R Hibbard, Jr , President J C Kinnear, Jr , Past President John Chipman, Vice-President T D Jones, Treasurer R W Shearman, Secretary AIME, 29 West 39th Street New York 18, N Y

Jan 1, 1958

Elected Died 1895 *ABBOTT, AI ATTHUR 1908 1882 *ABBOTT, ARTHUR V 1906 1905 * ABE, MASAYOSHI 1909 1903 * ADAMS, CHARLES C. 1905 1905 * ADAMS, WILLAMS 1909 1903 * ADAMS, W. EDWARDS 1910 1884 *ADDY, MATTHEW 1896 1906 * AFFLECK, WILLIAM A. 1911 1889 * AKERS, WILLIAMS 1906 1905 * ALABASTER, RUPPERT C. 1911 1899 * ALBERGER, LOUIS R. 1911 1894 *ALLEN R B 1896 1905 * ALLEN, R. SCOTT 1906 1874 * AMIOT, H. 1892 1886 *AMSLER, CARL 1894 1898 ** ANFERSON, JOHN w. 1905 1895 *ÅNGSTROM, CARL 1901 1887 * ARCHBALD, JAMES 1910 1900 * ARLETT, GEORGE H 1906 1895 *ARMSTRONG, JOHN F 1898 1882 *ARNOLDS, HUGO 1886 1875 *ASHBURNER, CHARLES A 1889 1872 *ASIIBURNER, WILLIAM 1887 1883 *ATKINS, C M , JR 1885 1905 * AUSTEN, PETER T 1907

Jan 1, 1917

By D S. Collins, Z Hosseini, I Pinnock, Y Toya

Microseismic monitoring is regularly used in the mining and geotechnical industries to provide detailed information about rock mass response to operational activities. This paper implements a variable 3D velocity model (VM) at a North American hard rock mine with the aim of further improving the accuracy of seismic event locations. A collapsing method is also used to help analyse two individual seismic event clusters at another North American hard rock mine. In the first case study, the location accuracy of events is shown to improve by moving from a conventional single VM to a variable 3D VM that accounts for voids and different geological domains. The modal average for the event location accuracy improved from 14 m to 5 m when the 3D VM was used. Additionally, the single VM failed to locate 26 per cent of the seismic events that were located by the 3D VM. In the second case study, the distribution of seismic events was further enhanced by using a collapsing method that highlighted planar structures. The collapsing method was performed on two large event sequences that occurred in close proximity and identified different seismic event distributions. One aftershock sequence aligned along a plane, suggesting an activated structure, while the other large event sequence had a more 3D distribution of events, suggesting a complex stress redistribution on smaller structures.CITATION:Pinnock, I, Collins, D S, Toya, Y and Hosseini, Z, 2016. Large event sequence analysis and 3D velocity models for seismic event location accuracy, in Proceedings Seventh International Conference and Exhibition on Mass Mining (MassMin 2016), pp 879–884 (The Australasian Institute of Mining and Metallurgy: Melbourne).

May 9, 2016

By Tyler Acorn, Paul Worsey, Nathan Rouse

The effect of the hole diameter on vibration attenuation has not been incorporated in most vibration models in the blasting industry. In current vibration models, the charge weight and the distance from the blast are the two primary variables that are addressed. Charge weight is a function of explosive density, charge length, and charge diameter. This geometry-weight can complicate the isolation of the charge diameter variable.

Jan 1, 2013

By R. E. Moore

The lining systems currently in use in BOF furnaces, certain steel ladles, and the slag line of electric are furnaces were developed during the late seventies through the mid-eighties using a trial and error method of combining aggregate, carbon sources, additives and binders. They are currently based on magnesia, graphite, metal additives and resin binders, the selections of each being tied to the anticipated intensity of the use conditions. The general functions of the respective constituents are well appreciated, however, there is still a great deal that is not known about how the socalled antioxidants protect the graphite nor how impurities from the graphite and the aggregate enter into the wear processes. In a simplified assessment of wear processes, it appears that if the deoxidized layer can be kept very thin, less than 810 mm in depth, and if the viscosity and quantity of the matrix glassy phases can be controlled to resist erosion of the deoxidized layer, lining life can be maximized for the various applications. This paper will discuss the characteristics of the starting materials systems currently being employed for applications requiring a deoxidation function to realize extended wear. It will not attempt to explain all the complex interrelationships between the respective constituents but will point to the potential for improvements through the use of improved constituents.

Jan 1, 1991

By Richard M. Whiting

Thank you very much for that introduction. I spent part of my early career in the coal industry here in Colorado, and I am always happy to return. In such a beautiful setting, it seems out of place to talk about "Improving the Climate". But in our work-a-day worlds, we know the climate for the coal industry is something less than picture perfect. But unlike Mother Nature's climate, there are some things we can do about the climate for coal. Today, I want to talk to you about sonic of the activities that we are engaged in... and that you can support... to improve that climate. A number of challenges and opportunities face our industry. I will try to set the stage for this conference by briefly describing the current climate for coal - which is indeed very challenging. I will then outline some of the steps we are taking to broaden our base to include our allies in the rail and electricity industries and the public at large.

Jan 1, 2000

By AIME AIME

M R. WEIGEL'S present position as Chairman of the Institute's nonmetallics group arises from twenty years of experience in that field, from 1921 to 1926 as mineral technologist for the Bureau of Mines, in Washington, and since then for the Missouri Pacific R.R. Co., with headquarters in St. Louis. This rail- road serves an extensive region in and about the southern central states, from Omaha to the extreme southern tip of Texas, and from southern Illinois to Pueblo, Colorado, and it is Mr. Weigel's job to get as much freight for the road as possible from the mineral industry in this area. Much of the present and potential mineral production is in the non- metallic group.

Jan 1, 1940

By O. W. Kamper

To most of you present here the word "refractories" is not new and you are familiar with the materials and use. To many people though the question is asked, "What are refractoriness and what are they used for?" Refractories are non-metallic products which are so resistant too melting at very high temperatures that they can be used for building or lining furnaces of all kinds. A large variation occurs in the size, form, and composition depending on the service for which they are intended. They are made from a wide variety of raw materials, of which fire clay and quartzite are used in largest quantities. Other refractory raw materials include magnesite, chrome, diaspore, bauxite, kyanite, sillimanite, olivine, zircon, and many others. Most of these are assembled from-widely-'separated points in the United States while others come from the far corners of the earth. Chrome is imported from the Philippines and South Africa, and, to a lesser extent, Turkey and Greece Kyanite and sillimanite come: from India and bauxite from the Guianas. And there's "magnesite from brines," produced in chemical plant's by treatment of sea water or inland deep-well brines with hydrated lime. The proportion of magnesia available in sea water is so small, less than one pound from 500 pounds of water,, that millions of gallons must be pumped and processed each day in a sea water magnesite plant. The realm of refractory raw materials, therefore, is very extensive and continues to grow because of the endeavor to find-better raw materials from which to produce better products for refractory service.

Jan 1, 1960

By Z. H. Li

In connection with the features of characteristic waste water (containing cyanogen, arsenic and heavy metal) pollutants discharged by gold industry as well as the environmental features at the location of gold production enterprises, this paper briefly described the traditional method of treatment, and focused on the argument for technologies of clean production, advanced treatment and process control technology. Moreover, it clarified the future policies and development trend for treatment on characteristic waste water from gold industry.

Jan 1, 2014

By Brandon Smith, William Bohlen

Riverbank erosion along the Brazos River has modified the structural support conditions for an existing bridge structure in Southeast Texas. The 8-span, 1,200-foot long bridge was completed in 1992 along Highway 99, a key corridor for the Houston area. Foundation support conditions have been altered due to natural, ongoing river morphology for three bents on the affected riverbank. Recent events include three storms within a three-year period that each exceeded the 500-year return probability. This resulted in accelerated erosion along the northern riverbank. Over forty vertical feet of soil has been removed in some locations. Drilled shaft foundations are now functioning as columns. This review considers the behavior of columns and deep foundation elements due to the modified support conditions. The review ultimately presents a rational methodology for the review of the present and anticipated future bridge configuration with respect to current strength, service, and extreme event limits, with corresponding safety factors for the design. Introduction and Background The Fort Bend Grand Parkway Toll Road Authority (Owner) oversees the State Highway 99 Judge Jodie Stavinoha Bridge over the Brazos River. The 8-span, 1,200-foot long bridge was originally designed with four southern approach spans of 115 feet; a three-span continuous river crossing with span lengths of 195 feet-235 feet-195 feet; and a single northern approach span of 115 feet. Figure 1 provides an overview of the northern portion of the bridge. Table 1 provides a summary of the original bridge substructure configuration. When the bridge was completed, the centerline of the Brazos River was located at midpsan of the main span and the northern high bank was originally located at Bent 7. Erosion process has forced the northern high bank to Abutment 9 (also called Bent 9), and the river centerline during normal flow conditions is located south of Bent 8. The overall estimated river excursion at present day is approximately 270 feet to the north from its original location. An erosion wall that was installed in 2017 limits further erosion of the north river bank within the 300-foot width of the roadway corridor right-of-way. This study was developed to better understand the existing conditions, and to forecast the need, nature, and criteria for potential future improvements.

Jan 1, 2019

By Junzo Hino

Most of the waste that contains a small portion of copper is landfilled. The recycling process of copper from the waste, such as shredder residue, should be developed in order to save mineral resources and prevent environmental pollution. Shredder residue, generated from disposed automobiles and electric appliances, consists of many types of plastics, glasses and metals. The combustion heat of plastics is efficiently used for smelting in the recycling process that consists of melting and reduction. Because the waste contains numerous components the knowledge of the distribution behaviors of the main components is necessary to develop the recycling process. The distribution behaviors in the recycling process are evaluated by using the thermodynamic calculation program, HSC Chemistry. The calculation results are compared with the practical operation data of the recycling process and discussed.

Jan 1, 2003

FEBRUARY 26TH. MORNING SESSION: The sixteenth regular meeting of the Rocky Mountain Coal Mining Institute was called to order in one of the private dining rooms of the Albany Hotel, Monday morning, at 11 o'clock, with the President, F. W. Whiteside, in the chair, one hundred and one members being registered. The minutes of the previous meeting were read and approved. The Treasurer reported the finances of the Institute in excellent shape. The President appointed J. B. Marks, J. S. Veach and W. A. Ream as a Resolution Committee, and Frank A. Young, M. B. Urquhart and G. A. Murphy a Nominating Committee. There being no further business the meeting adjourned. AFTERNOON SESSION: The afternoon session was called to order in the Ball Room of the Albany Hotel, with approximately one hundred members present, President Whiteside presiding. A. L. Jones read his paper entitled, "The Power Problem of the Coal Mine," and C. E. Drennan, his paper, "Why Alternating Current." These papers were thoroughly discussed, after which the meeting adjourned. EVENING SESSION: At 6:45 p. m. two hundred and fifty-three members and invited guests met in the Ball Room of the Albany Hotel for the banquet. Harry F. Nash was toastmaster, and George Sanford Holmes the principal speaker. Following Mr. Holmes speech, H. N. Wheeler delivered his humorous oration of the "Annexation of Cuba;" following this certain members of the Institute gave an entertainment depicting a fictitious meeting of the United States Coal Commission. Chester Mott, formerly a member of the Institute wrote the words and songs of the entertainment, and directed it. After the show the assembly enjoyed a dance.

Jan 1, 1923

By R. T. Richins

Coeur d'Alene Mines Corporation (CDE) is a precious metals mining company. The company's three mining operations are located In Nevada and Idaho. Collectively, these mines (Rochester in Nevada, and the Galena and Coeur In Idaho) produced about 61,000 ounces of gold and more than 7.5 million ounces of silver in 1991. The company is currently planning the development of two major properties; the Fachinal gold-silver project in Chile and the Kensington gold project near Juneau, Alaska. Fachinal and Kensington hold encouraging potential to significantly expand CDE's gold production during this decade. The permitting process for these two distinctly contrasting environmental settings, project design requirements and regulatory/political circumstances provide the basis for a comparative analysis of licensing and permitting requirements, timeliness of the permitting process and costs in the U.S. and Chile.

Jan 1, 1993