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By Donald A. Bruce

Pin Piles are small diameter, bored, cast-in-place piles used to underpin structures. They were first employed over 40 years ago in Italy, and have been used in the U.S. since the late 1970's. However, it is only in the last few years that their full potential in terms of load holding capacity has been exploited: whereas 100 kip working loads typified former practice, ultimate loads approaching 700 kips have recently been recorded for Pin Piles founded in sand. In order to better understand the actual performance of these piles, fundamental research has been conducted by a consortium of industry and academia. This paper describes the advances made in the laboratory and full scale field testing programs. In particular, the extensive field tests have been conducted in a variety of materials in which different pile configurations have been cyclically tested to failure. By using this test method, the elastic performance of the piles has been examined and so the progressive interfacial debonding phenomenon has been studied. This has led to the development of the Elastic Ratio concept which is proving extremely useful in analyzing and predicting Pin Pile performance. Data are provided from the full scale Test Pile Programs conducted at Mobile, AL and Port Vancouver, WA. Given that Pin Piles are usually installed in areas of low headroom or restricted access, and through difficult, occasionally contaminated soils, the paper also describes key aspects of construction.

Jan 1, 1993

By Mayfield P. L J, Honeyands T. A

BHP's two million tonne per annum nominal capacity Hot Briquetted Iron (HBI) plant at Port Hedland in the Pilbara region of Western Australia is based on FINMET¦¦ direct reduction technology. The FINMET¦¦ process produces direct reduced iron (DRI) by reacting fine iron ore with reformed natural gas in a series of fluid bed reactors and then hot briquetting this DRI into dense, high quality iron briquettes. The Port Hedland HBI project represents a major investment in the chemical processing of Australian minerals to higher value products prior to export to Asian markets. This paper describes the FINMET" process and technical aspects of the high-quality HBI product, and provides an update of the current status of the project.

Jan 1, 1999

Impala Platinum?s No.16 Shaft mine is currently under construction and is expected to reach full production of 256 500 tons per month by 2014. Mining will start at 1 260 m below surface with a maximum mining depth of 1 535 m where virgin rock temperatures of 56.6°C will be experienced. As a result of depth, high virgin rock temperature and narrow reef mining, an expected total of 31.5 MW[R] of air cooling capacity will be required to achieve acceptable underground conditions. This will be achieved by cooling mine intake air in a single dedicated air cooling installation located on surface. The compact installation includes air cooling spray chamber, refrigeration machines, condenser cooling towers, evaporator and condenser water reticulation as well as all electrical and control systems. Construction and commissioning of the first phase of this air cooling installation has recently been completed on a turn-key contract basis.

Jan 1, 2009

By R. A. Isberg

This report describes the design and implementation of UHF radio and closed-circuit television systems in the Black River room and pillar limestone mine near Butler, Pendleton County, Kentucky. Prior to designing the radio system, measurements of signal attenuation on 812 and 466 mHz were made in the slope tunnel and in the straight and level crosscuts in the mine. Two distributed antenna systems fed by two sets of base stations provide approximately 75o coverage of the mine. Passive reflectors are used for extending signals into intersecting crosscuts and two-way signal boosters will be used to extend signals to the perimeter and obstructed areas of the mine. Fourteen mine vehicles were equipped with mobile radios equipped with digital identification, alarm and status encoders. Fifteen portable transceivers also were used. Six closed-circuit television cameras provide surveillance of critical transfer points of the belt conveyor system, and the loading dock at the base of the slope and an ash disposal area in the mine. Two-way radio communication and closed-circuit television have saved considerable man. hours, increased production, reduced maintenance costs and enhanced safety. Innovative developments were the use of passive reflectors and two-way signal boosters for extending signals into intersecting crosscuts, development of lightweight signal margin measuring equipment, modifications of mobile digital encoders to automatically send status information from mine vehicles such as numbers of loads of ore delivered, hot engine, etc., and the use of CATV technology for multiplexing audio, digital and video signals onto coaxial cables from the surface to the mine.

Jan 1, 1981

By D. Potter

In 1990, Freeport Exploration began regional reconnaissance exploration programs in Irian Jaya, the easternmost province of the republic of Indonesia (Fig. 1). Irian Jaya occupies the western half of the island of New Guinea. Freeport was awarded an initial contract of work that totaled 2.6 million hm2 (6.4 million acres). The company was subsequently awarded additional concessions that added 1 million hm2 (2.5 million acres). The concessions require work commitments and periodic relinquishments. Due to these relinquishments, Freeport’s current land position totals 1.9 million hm2 (4.7 million acres). Freeport began the exploration program to locate additional Grasberg deposits, the largest deposit in the Ertsberg district. But the company recognized that other types of deposits could be present in the largely unexplored area of Irian Jaya.

Jan 1, 1999

By Stephen H. Chung

The SABREX computer blast simulation program permits the study of the effective use of explosive energies and predicts the total performance of a blast in terms of:fragment size distribution: muckpile profile; breakage at grade, column and collar with respect to the control case; crack penetration; damage envelope behind and beneath blastholes; a complete cost analysis including explosives, drilling and accessory costs

Jan 1, 1995

By R. F. Tenney

The performances of four anthracite-burning stokers have been observed under identical 74-hp. steam boilers. Fifty runs of 12 and 24 hours' duration were made in accordance with the test code of the American Society of Mechanical Engineers (ASME). The capacity of each stoker for burning anthracite has been determined, the heat efficiency at each fuel rate has been computed, and the various significant items of hear loss have been estimated. The operating data and results from each run are tabulated in this report in the form used in the test code. The heat efficiencies and most significant operating data for each run are also presented graphically for each stoker to establish the trends with increasing boiler outputs, The tests show that rice anthracite can be burned on stokers adapted to its use at heat-conversion efficiencies of 82 percent or more under continuous firing. These high efficiencies are maintained with fuel inputs 30 percent higher and lower than the peak efficiency rate. Moreover, a heat efficiency of 70 percent or more is obtained at 50 percent of the optimum fuel rate, even though the excess air into the furnace cannot be held below 150 percent.

Jan 1, 1960

Who's Who in Mineral Engineering - The 1978 Membership Directory of the Society of Mining Engineers of AIME

Jan 7, 1978

By Harold Price

ONE year ago, that is in January, 1923, there had not been constructed a single oil-storage tank of 55,000-bbl. or more capacity with a completely electric welded roof and bottom. Today, there are at least fifty 80,000-bbl. storage tanks completed, or nearing completion, on which both the roofs and the bottoms are electric welded. It is the purpose of this paper to describe, in a general way, the construction of these FIG. 1.-ELECTRIC-WELDED SEAMS AND RIVETS OF BOTTOM IN 55,000-BBL. TANK AT EL DORADO, KANS., SHOWING ALSO PATCH PLATE WELDED TO BOTTOM. welded roofs and bottoms, and to give their advantages over riveted construction. All of the following data and conclusions were obtained from observations made during the welding of tanks by the Welding Engineering Co. at Texas City, Tex., and Tonkawa and Burbank, Okla. As far as can be determined, the first electric welding on large tankage was completed in May, 1922. At that time the Empire Companies of Bartlesville, Okla., discovered a badly leaking bottom in a 55,000-bbl. tank at El Dorado, Kans. They had considered concreting this bottom, but because of the much smaller cost, decided to try electric welding; so a- contract was given the Welding Engineering Co. of Bartlesville, Okla. In this instance, no new sheets were added, the bottom being repaired by electric welding of all seams and rivets, Fig. 1. In some places where the original rivets were missing, the holes were filled by welding; patch plates were also added at certain badly worn spots. This tank has since been in service over a year and half, but no other

Jan 6, 1924

By Flavio Begazo Mamani

Recientemente Southern Perú desarrolló un nuevo proyecto donde se modernizaba la planta de Fundicion y se reemplazaba el convencional horno reverbero por la tecnología del ISASMELT, capturando más del 92% de los gases generados durante el proceso de fusión de los concentrados de cobre. En ese sentido, el presente texto describo los efectos de la modernización de la Fundición sobre la calidad anódica. Antes de la modernización de la Fundición, los ánodos fueron producidos en la planta de ánodos ubicada en la Refinería de Cobre de Ilo. Ahora los ánodos son producidos directamente en la Fundición y como resultado, la composición química de los ánodos ha cambiado, principalmente en el contenido de bismuto, antimonio, plomo y zinc, siendo diferentes a los parámetros de diseño original de la Refinería. Asimismo, este factor impulsó a revisar el proceso de remoción de impurezas y los parámetros de la refinación electrolítica en la Refinería para evitar la contaminación del cobre refinado, logrando mantener la continuidad de la producción de cátodos de cobre de alta calidad superando los estándares interna-cionales de la norma ASTM-B115.

Sep 12, 2011

By Kumar A, Mishra N. C

For each tonne of chromite ore mined in Sukinda, approximately ten tonnes of fine overburden material is generated. The overburden typically contains about 30 - 60 per cent Fe2O3, 0.3 - 1.1 per cent Ni, four to nine per cent Cr2O3 and 0.04 - 0.2 per cent cobalt and is being discarded leading to loss of valuable metals and creating environmental pollution. In order to take the advantage of presence of iron, nickel and chromium, the present studies advocate the utilisation of nickel lateritic chromite overburden for production of Ni bearing pig iron through blast furnace extracting maximum iron and nickel from the chromite overburden. The present paper deals mainly with the beneficiation of chromite overburden, sintering characteristics and thermodynamic studies. The beneficiation study shows that a beneficiated concentrate having Fe - 50 per cent and Ni -- 1.1 per cent can be achieved from chromite overburden having Fe - 30 per cent and Ni -- 0.7 per cent. Sintering studies have been carried out with bed height of 300 and 450 mm at a suction of 600 and 900 WG respectively. The results reveal that good quality sinter can be produced from chromite overburden concentrate with a basicity of about 1.0 and coke breeze consumption rate about 16 per cent. In all the experiments, Tumbler Index, Abrasion Index and Shatter Index was found to be in the range of 65 - 70, 4.5 - 5.5 and 85 - 90 respectively. The other parameters namely softening temperature, melt down temperature, reduction degradation test and relative reducibility have also been determined. A thermodynamic analysis has also been carried out to make a technological assessment of the process for the production of alloyed pig iron from chromite overburden in blast furnace which shows that it is possible to produce nickel bearing pig iron in blast furnace using the sinter up to 80 per cent. Techno-economic analysis reveals that this route will yield a substantial profit even after accounting for cost of beneficiation, extra coke, raw materials and extra slag produced.

Jan 1, 1999

By L. V. Clark, Arthur La Motte

"INTRODUCTION The U. S. Bureau of Mines in 1930 and 1931 made a study of the properties and characteristics of liquid-oxygen explosives (L.O.X.) at the request of one of the largest users, in order to determine and eliminate the hazards attending its use.This report deals with the examination of absorbents for L.O.X. to (1) determine their most desirable and most undesirable characteristics, (2) to find ways and means of desensitizing absorbents to mechanical shock, and (3) to determine the effect that such desensitization of absorbents has on the explosive Characteristics of L.O.X.ABSORBENT MATERIALS The absorbent used in driving the Simplon Tunnel, the earliest project in which L.O.X. was used, was composed of crude petroleum, soot, and kieselguhr. During the World War, powdered cork, soot, sawdust, powdered straw, or other similar powdered materials were mentioned in the German military instructions for use of ""liquid air"" explosives. At that time the common types of absorbent, materials were compounded ones containing the above ingredients as well as kieselguhr, paraffin, gas oils, charcoal, bituminous coal, etc.Kuryla and Clevenger4 investigated absorbents of the above type and made the following statement concerning them:"

Apr 1, 1932

In a previous paper of this series (1) ,t it was shown that during the creep of single crystals of lead, deformation proceeded to some extent by means of slip on the octahedral plane. This was demonstrated by the formation of slip lines on the surface of the specimens. At first, a few broad bands appeared after a small amount of extension had taken place; then, as extension proceeded, more and finer lines made their appearance until the whole of the specimen surface was covered.The present paper deals with the process of deformation of the creep specimens as revealed by X-ray examination..By the use of this method, the changes taking place in the crystal structure can be observed.EXPERIMENTAL METHODThe method of preparation of the specimens, their size and the purity of the lead employed have been reported elsewhere (1). At frequent intervals, the specimens were dismantled from the test rack and X-ray back reflection photographs were taken. The specimens were so marked and set up on the X-ray machine that the same spot on the specimen surface was always examined.Copper radiation was employed, the tube voltage and current being 45 kV. and 25 m.a. respectively and the exposure time 2 hrs. The slit diameter was 1 mm.

Jan 1, 1941

Electroosmotic Dewatering and Consolidation of Mineral Waste Tailings

Sep 13, 2010

By M. C. Makepeace

"It is the objective of designed experiments to obtain more information for less material and process cost than can be obtained by traditional experimentation. In this paper, the fundamental concepts on which the statistical design of experiments is based are briefly re-viewed according to the following outline: The Experiment The Design The Analysis Two simple 2"" factorial experiments are presented as examples."

Jan 1, 1967

By J. D. Noll, S. E. Mischler

Measurement and sampling of diesel particulate matter in mine air presents a challenge due to the complexity of the diesel aerosol. The results of a series of tests carried out by the National Institute for Occupation Safety and Health, Pittsburgh Research Laboratory, in an underground mine were used to evaluate several measurement methods that are currently used to characterize particulate matter emitted by diesel-powered equipment. This paper presents an overview of these techniques and examples of the results along with a discussion of the advantages and information gained by each technique. The measurement methods discussed include particle size measurements using a scanning mobility particle sizer, total particulate matter measurements using a tapered elemental oscillating microbalance, a size selective sampling method for workplace and personal exposure assessment and a size-selective high volume sampling method for carbon analysis.

By Michael L. Clar

This volume is an annotated bibliography of published literature pertaining to the occurrence and control of surface and groundwater in underground coal mines. This literature was used to develop Volume 1 of this report, which assesses the feasibility of water diversion and overburden dewatering for underground coal mines in the Appalachian Region. Each abstract is followed by subject descriptors. the abstracts are listed alphabetically by title and are numbered consecutively. These numbers are used in the subject index to help the reader locate the appropriate articles.

Jan 1, 1981

By K. Morita, N. Sano

Thermodynamic properties of chromium oxides in molten slags are very important for optimization of stainless steel refining processes as well as reduction processes of chromium ores. The solubility of chromite into molten slags has been found to vary considerably with oxygen partial pressure and slag composition in former studies by the authors. In the present study, activity data and redox equilibria of chromium oxides measured under moderately reducing conditions, PO2= 6.95x10–11atm, at 1873 K are summarized. For the CaO-SiO2-CrOXsystem, the activity coefficient of chromium oxide increased with increasing basicity, and the optimized slag composition for stainless steel refining is assessed as that saturated with CaCr2O4and Cr2O3usingthe phase relations determined. On the other hand, the presence of MgO and Al2O3brings about different behaviour of chromium oxide activity and redox equilibiria and the 44 mass per centCaO-39 mass per cent SiO2-11 mass per cent Al2O3-6 mass per cent MgO slag is recommended toreduce the chromium oxidation loss in the practical stainless steel refining process at 1873 K. Keywords: chromium, activity, stainless steel, AOD, VOD, oxidation loss, redox, CaO-SiO2-Al2O3-MgO slag

Jan 1, 2004

By Z S Chang, T F. Zhou, G X. Zhong

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Yaojialing zinc-gold polymetallic deposit is a newly discovered, large skarn deposit in the Middle-Lower Yangtze metallogenic belt, East China. It is located in the transitional zone between the Tongling uplift block and the Fanchang faulted basin. It is mainly hosted in the contact zone between early Cretaceous granodiorite porphyry and Carboniferous-Triassic limestone, or occurs in limestone xenoliths within the intrusion. Skarn and stratabound massive sulfide orebodies are the primary ore styles. Sulfide ?34SV-CDT values indicate a magmatic sulfur source, in common with most deposits in the Tongling block. Calcite d13CV-PDB and d18OV-SMOW ratios reveal that marine carbonates were the major source of carbon in late-stage hydrothermal fluids. The calcite probably formed during interaction between magmatic fluids and carbonate wall rock.CITATION:Zhong, G X, Zhou, T F and Chang, Z S, 2015. Geology, chronology and isotope geochemistry of the Yaojialing zinc-gold deposit, Tongling ore district, Anhui Province, China, in Proceedings PACRIM 2015 Congress, pp 457–462 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015

By Michael S. Kucker, Stuart Warren, Robert A. Robinson, Michael J. Lehnen, David McAllister

Geotechnical conditions exposed by the phased exploration programs have had a major impact on the selection of excavation and support methods, dewatering requirements, size of openings, vertical alignment, and estimated cost of construction for the Beacon Hill Tunnel and Station section of the “Link” Light Rail. Beacon Hill is comprised of a very complex glacial geology, including numerous slickensided fractures, injected sand dikes, and multiple perched groundwater levels as revealed by a phased boring program and exposed in a test shaft. The Geotechnical Baseline Report (GBR) presents this complex geology along with a “tool box” of alternative additional support systems to accommodate the varying ground conditions during construction of the station excavation. Additional explorations will also be accomplished during construction to further refine the geotechnical interpretations and provide an opportunity to use pro-active ground improvement techniques to optimize the station excavation and support requirements.

Jan 1, 2005