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By F. J. Klingler, R. Hausmann, K. M. Swaffar, J. C. Neyer

This paper presents the results of a study of case histories of projects on which sinking caissons were used to construct shafts for tunnel construction and other underground works. Design methodologies are reviewed with respect to the impact of soil and groundwater conditions on the performance and constructability of sinking caissons. Factors which have led to success or failure are reviewed and evaluated, and recommendations for future investigation, design and construction activities are presented. Cost data for five recent projects are reviewed and compared to the cost of shaft installation by other means.

Jan 1, 1997

By S. Rupprecht

Project evaluations of mineral deposits are necessary for mineral rights, owners and investors alike. A feasibility study provides a definitive technical, environmental and commercial base and is the key element leading to a decision to invest or not to invest. For example, the study may be used to justify further exploration and development expenditure or to provide a basis for a major underwriting to raise the required capital. There are three distinct phases in the development of a project and the type of study will differ depending on the quality of information available or the level of decision to be made. This paper looks at these three phases in the development of a mineral project and the type of study required; namely, a scoping study, prefeasibility, and a full feasibility study. Keywords: scoping studies, feasibility studies, mining projects.

Jan 1, 2004

By Anand Bhagwat

Surface control can prevent the falls of ground between primary roof support systems and rib support. Using existing industrial products, and adopting them for mining applications, has historically attained surface control in underground mining. However, the latest innovative solution, a revolutionary wire mesh product, is designed specifically for underground mining applications jointly by Bekaert and Orica. This knotted wire mesh, FlexKnot? 2500 and FlexKnot? 3500, uses smaller gauge, higher tensile strength wires, than a chain link fence or welded wire mesh. The higher tensile wire enables the mesh to achieve greater ultimate load-bearing capacity, with significantly lower overall weight. Test results, obtained at the National Institute for Occupational Safety & Health (NIOSH) Mine Roof Simulator facility, illustrate the comparisons of the new FlexKnot with traditional 8- and 10-gauge welded steel mesh. The FlexKnot is superior in deflection, load-bearing capacity, and stiffness?categories that are critical in achieving safer surface control. It also offers enhanced corrosion resistance because of the galvanized coating applied on the individual wires prior to the knotting process. Case studies from underground coal mine installations confirm that FlexKnot has the ability to significantly reduce installation cycle time and to minimize use and repetitive manual handling of individual mesh panels. An added advantage is the ability to supply FlexKnot in rolls for quick and easy handling for either rib or roof support application. When using rolls, the bolter can install the entire roll with one continuous forward motion, unlike the wasteful back and forth travel for mesh panel.

Jan 1, 2014

Jan 1, 1948

Jan 1, 1948

By Roger M. Sherman

[Investigation of mine land characteristics, evaluation of irrigation systems, and evaluations by the mining industry, determined that irrigation is a feasible method for aiding revegetation of coal mined lands in western arid and semi-arid regions. The various regions studied displayed a commonality of characteristics which enables, independent of the site or region, the recommendation of solid set irrigation. Irrigation should be supplemental by complimenting natural precipitation and be should implemented on a temporary basis.]

Jan 1, 1980

By Oliver Bowles

"Asbestos" is a name applied to a group of naturally fibrous minerals. Because it has the fibrous characteristics of silk or cotton and at the same time will not burn and has other advantageous properties as well, asbestos has specialized uses for which no adequate substitutes are yet available. Asbestos furnishes a major raw material for a great variety of essential products, the manufacture of which constitutes a vast industry. Asbestos generally occurs in irregular veins scattered throughout rock masses. Most of the fiber-bearing rock is mined in huge open-pit or underground workings. The fibers are separated from the rock and sorted into groups, according to length, in large, complex mills. The longer fibers are stripped to textile plants, where they are further fiberized and prepared in special machines and are used for spinning into yarn and weaving into unburnable cloth that has many important uses. The shorter fibers, which are much more abundant than the long ones, are used in asbestos-cement building materials in heat-insulating products and for a multitude of other applications. These processes and uses are covered in considerable detail in later sections of this report.

Jan 1, 1959

By Eugene Fry

The Huber-Rydalch manganese property is in the Erickson mining district of Tooele County, Utah. The district covers the southern part of Simpson Mountains, a block rising abruptly above the surrounding desert floor (fig. 1). The Ruber-Rydalch deposits and other deposits in the Simpson Mountains manganese area were examined by Bureau of Mines engineers during 1940 and 1942 under the strategic minerals program. J. T. Pardee visited the district briefly in 1918. A. E. Granger and A. F. Shride, of the Federal Geological Survey, mapped the geology of the area in 1942 and 1943. The manganese deposits occur as veinlike masses in brecciated fault zones that traverse Cambrian and pre-Cambrian quartzite, quartzite conglomerate, and phyllite. The deposits now exposed near the surface represent the oxidized portions of primary mineralization originally containing rhodochrosite and rhodonite associated with quartz and calcite and small quantities of pyrite, galena, sphalerite, and chalcopyrite. The oxide ore is composed of manganite, pyrolusite, psilomelans, and wad in a gangue of quartz, calcite, and brecciated quartzite.

Jan 1, 1949

By Oscar Restrepo, Juan C. Nino, Henry A. Colorado

New and extraordinary physical-chemical properties of materials at nanoscale open up new applications for the building and infrastructure industry such as structural reinforcements, electronic properties and energy harvesting. Therefore the issues and risks associated with the manufacturing of nanomaterials are now of big concern due to the large volumes and typical processing involved in this industry. This paper presents a discussion and selected applications of nanotechnology in the construction and building materials: from metals and alloys, clay and minerals, ceramics, cement and concrete, asphalt, wood and composites, to finishing systems and some of the most used characterization techniques. Besides the progress in some areas, nanotechnology is just emerging in this field, with many challenges and opportunities, problems unsolved and business opportunities. A discussion regarding the potential health issues and risks of using nanomaterials for workers and the potential environment effects is included as well. New images and diagrams are presented and discussed.

Mar 1, 2018

Many USBM research and information products are available through the systems or formats listed below: Mines FaxBack: Return fax service. 1. Use the touch-tone handset attached to your fax machine's telephone jack. (ISDN [digital] telephones cannot be used with fax machines.) 2. Dial 202/219 3644. 3. Listen to the menu options and punch in the number of your selection, using the touch-tone telephone. 4. After completing your selection, press the start button o your fax machine. Mines Data: Computer bulletin board. Log on via modem through 202/501-0373, or call 202/501-0406 for technical assistance. CD-ROM: This USBM disk is updated quarterly and sold by GPO's Superintendent of Documents. For information on the latest product, please contact Rodger Wedgeworth, 202/501-9557. Internet/World Wide Web: Text and graphics. Access via PC-based browsing software such as Netscape or Mosaic. Universal Resource Locator (URL) is: http:/www.usbm.gov Internet/Gopher Server Text and tables only. Using Gopher client software, access via port 70 as follows: gopher.usbm.gov Internet System Administrator: webmaster@usbm.gov (or contact your local System Administrator).

Jan 1, 1995

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 T. Hawthorne, H. Barnes

Homestake Mining Company has developed an estimating model, based on other closed projects, to audit and prepare new estimating plans. The results of recent closure audits reveal that the original budgets were often insufficient to cover the present expected expenses. Some of the major areas where technical challenges and costs are increasing include heap leach pile detoxification and rinsing, tailings dam closure, water management and treatment, abatement of contaminated soils, and many others. Risk and sensitivity analysis of each category will develop a level of confidence in the estimate and allow management to focus on the pertinent issues. Periodic audits of closure plans and costs throughout the life of mine serves to focus management attention on the complete costs of production. This will result in improved overall planning and management, and reduce the number of missed opportunities for savings.

Jan 1, 2000

By M. Boodman, E. Gertner

"At first glance, the activities related to mining and mineral exploration appear to be local or domestic, rather than international, in nature. Minerals, as corporeal or tangible property, form an integral part of the land in which they are found until extracted and exploited commercially. Even in the latter phase, the tangible nature of minerals gives the impression that the law governing the commercialization of minerals is the law of their situs at any given time. The nature of minerals appears to negate the international aspect of mineral enterprises.The fundamental flaw in the above analysis is its focus upon the nature of minerals, rather than the role of persons in mineral enterprises. The high costs of mineral exploration and commercialization invariably require the involvement of international consortiums or joint ventures. Governments may not have access to the funds necessary to exploit the mineral resources that they control. Local or domestic enterprises may not have sufficient expertise for mineral exploration. Further, markets for various types of minerals are far from localized or static. For these and other reasons, the tangible and localized nature of minerals belies the fundamentally international nature of mineral exploration and commercialization."

Jan 1, 2004

The Mineral Industry, Published by McGraw-Hill Book Co, New York, N Y. The Mineral Industry is an annual review of the mineral industry It is a standard and complete reference on the mineral industry for the year covered Through the cooperation of the A I M E its publication in 1933 was made possible Mineral Industry for 1930 contains sections devoted to the production, consumption, trade, market, uses and technology of the following headings: Abrasives, aluminum and bauxite, antimony, arsenic, asbestos (b), asphalt, barium and strontium, chromium (b), coal and coke, cobalt (b), copper, diatomite, fluorspar, gold and silver, graphite, gypsum, iron and steel (b), lead, magnesite, manganese, mica, molybdenum, nickel, petroleum and petroleum products, phosphate rock (b), platinum group metals (b), potash, precious and semiprecious stones (b), quicksilver, radium (b), uranium and vanadium, slate (b), sodium salts, sulfur, pyrite, sulfuric acid, talc and soapstone, tin, titanium and zirconium, tungsten (b), zinc, minor metals, minor nonmetals, ore dressing and coal washing (b). Sections marked (b) have appended a bibliography of recent literature on the subject. Each section is written by an acknowledged expert. Other volumes contain similar material Prices -The Mineral Industry, 1892-1930, vols. 1 to 39. Complete sets of this work, uniformly bound, except vols 25 and 26,

Jan 1, 1933

By Fernando Pajuelo Rincón

El presente trabajo describe la explotación del cuerpo mineralizado Barnabé en Huarón, donde es interceptado por una veta a través del uso de un equipo LHD neumático y del vehículo LHD -EH. No obstante, es válido mencionar algunas variantes aplicados al método del minado a partir de la estructura de la veta Rey, a fin de alcanzar una explotación selectiva y aumentar el valor de la tonelada del mineral. En ese sentido, las variantes aplicadas al método se dan en base a la flexibilidad del equipo de limpieza, reduciendo los costos de minado en los tajeos Barnabé y Rey.

Aug 26, 1988

By Eugene T. Sheridan

The United States has extensive reserves of peat. Peat and muck lands are estimated at approximately 79 million acres, with reserves of 13.8 billion net tons. Within the past decade domestic production of peat has increased 2-1/2 times, and apparent consumption has tripled. During the same period imports have increased greatly, and in 1955 they almost equaled domestic production. The substantial increase in the demand for peat in the United States was due chiefly to expanding markets in agriculture and horticulture, for the reason that in this country peat is used primarily as a source of organic matter to improve the physical condition of mineral soils and as a mulch for shrubbery. A valuable constituent of any soil is its organic matter, and its depletion will injure cultivated soils and subject them to greater erosion.

Jan 1, 1957

By J J. Boshoff

This iron ore mine site, located in the Pilbara region of Western Australia, commenced operations in 1998, with ore derived by mining of open-cut pits in Channel Iron Deposits (CIDs). A portion of the ore extracted at the mine is processed at wet processing plants that produce both ore saleable product and waste fines (i.e. tailings) slurry. The waste fines produced at the wet plants are presently stored within Waste Fines Cells (WFCs).Waste fines cells A (WFCA) and B (WFCB) are located within an Autonomous Haul System (AHS) area and consist of embankments that span the width of the pit in east-west alignments. Technical studies and design analyses were carried out to support embankment raises and ongoing development of the WFCs. During operation and development of the WFCs, a multitude of simultaneous activities took place to the immediate north and south of WFCA respectively. These activities included the construction of the embankment raises using the AHS fleet, mining of the CID to not only mine the ore but to also create future deposition space for WFCB, blasting next to the WFC embankments as part of the mining activities, seepage collection and dewatering of the pit in the vicinity of the WFC.This paper discusses the material characteristics, design approach, construction staging and equipment requirements, blasting near embankments, water management, facility consequence category and closure concept.CITATION:Boshoff, J J, 2018. A waste fines cell with a multitude of concurrent activities, in Proceedings Mine Waste and Tailings Stewardship Conference 2018, pp 39–49 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 23, 2018

By Luiz Guilherme Isfer Maciel, Marilena Cardu, Fernando Golin, Jacopo Seccatore

"This study applies the concept of the difficulty of tunnelling by drilling an blasting (D&B) to selectedcases from the Brazilian tunnelling industry. The difficulty of tunnelling has been defined in previouswork as the difference of specific drilling (SD) from industrial average trend: easier when SD is lowerthan average, more difficult when SD is higher than average. Results show how tunnels in Brazil tend tobe unrealistically more difficult to excavate when compared to similar excavations in similar geologies elsewhere in the world. It is thoroughly discussed the reason for such anomaly (up to +90% SD compared to industrial average). One reason could be the lack of options amongst explosive products on the brazilian market. Only ANFO and explosive emulsions are available in Brazil. Lacking high VOD(Velocity of Detonation) products might result in reducing the maximum allowable burden amongstproduction holes, therefore increasing SD. Another reason could be found in the tunnel designers’tendency of choosing D&B as excavation method for weak rock masses that would benefit from mechanical excavation. The reason to this tendency can be partly found in the lack of availability of mechanical excavation machines in the brazilian market. Blasting in weak rock masses requires more careful smooth blasting, hence a closer spacing amongst contour holes to avoid costly overbreak: this increases SD. A third reason could be found in the lack of skill amongst the local workforce. When dealing with unskilled workers the blast designers naturally tend to avoid highly optimized blasts thatrequire very skilled workforce to be realized on field. The designer in this case tends to leave the blastdesign simpler but more robust, at the cost of higher specific drilling and specific charge. The conclusions suggest that this unrealistic difficulty when compared to world average could be a simptom of the so-called “Brazilian cost” within the tunnelling industry."

Jan 1, 2017

By S. Kwon, J. W. Wilson

"In salt and potash mines, the time-dependent deformation mechanism should be clearly understood based on in situ measurements to predict the performance of a mining design. In this study, in situ deformation measurements from the Waste Isolation Pilot Plant (WIPP) and other salt and potash mines were used to determine the transition time from the primary to the secondary creep stage and to investigate the influence of adjacent excavations such as a nearby tunnel excavation, panel excavation and/or pillar extraction on rock deformation. IntroductionThe deformational behaviour of underground excavations in salt and potash mines is complex due to the time-dependency of the rocks. When the material properties are determined from laboratory tests, they should be carefully applied to in situ conditions, because in situ conditions are completely different from laboratory conditions. For instance, in situ deformation measurements show that the deformation rate decreases with time similar to those observed in the laboratory during the early stages. However, the rapid decrease of deformation rate does not come from the microscopic strain hardening effect observed in laboratory tests, but mainly from stress relief around the opening after its excavation (Baar, 1977). It is, therefore, recommended to undertake in situ measurements and use them to understand the deformation mechanism.Even though in situ measurements are widely accepted as important information for understanding the deformation mechanism of salt and potash (Barr, 1971; Kovari and Amstad, 1993), not many publications have focused on the fundamentals of data measurement, the application of the measured data, and the development of data analysis techniques. Recently, several new techniques for better understanding the deformation mechanism of rock salt have been developed that are based on in situ measurements. Kwon and Miller (1995) developed a new technique for describing the actual deformational behaviour of an underground excavation in rock salt. The migration of “zero strain boundary,” which represents a no movement boundary around an underground excavation, could be calculated by the technique developed by Kwon and Miller (1996). Kwon and Wilson (1997, 1998) applied neural network techniques to in situ deformation measurements to predict the deformational behaviour of the underground excavations at the Waste Isolation Pilot Plant (WIPP) located in the United States.In this study, in situ deformation measurementsfrom the WIPP site and other salt and potash mines in the United States were extensively analyzed to understand the deformation mechanism of the underground excavations in the rock mass."

Jan 1, 2002

By James R. Boyle

The value of Alabama's nonfuel mineral production in 1980 was $328.6 million, a decrease of $7.8 million from 1979. Cement, crushed stone, lime, clays, and sand and gravel continued as the major commodities produced. Alabama led the Nation in the production of crushed marble; was second in bauxite; third in native asphalt, ferroalloys, kaolin, and oyster shell; fourth in dimension marble, masonry cement, and bentonite; and fifth in fire clay and lime. Alabama ranked in the top 20 States in total value of non-metallic minerals produced. Adverse economic conditions in the construction and metals industries impacted on the minerals industry in Alabama. Mineral producers supplying raw or finished materials to these industries experienced periodic reductions in sales during the year. Unit price increases did not keep up with inflation.

Jan 1, 1982