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"1 INTRODUCTIONThe use of nondestructive testing (NDT) methods to evaluate the integrity of Augered Cast-in-Place (ACIP) and Drilled Displacement (DD) piles has been a subject of significant debate among engineers, contractors and NDT practitioners. This guideline document will illustrate the importance of reviewing all available information in conjunction with the NDT records. ACIP and DD piles have unique properties that must be considered when using a specific NDT method. Any evaluation of the integrity of an ACIP or DD pile must also include a thorough review of the detailed pile installation records and the site specific soil conditions. Long or theoretical descriptions of the methods have not been included in this publication. More detailed information about these NDT methods including their theoretical and historical backgrounds can be found in DFI’s Manual for Non Destructive Testing and Evaluation of Drilled Shafts (2004). Additional information can also be found in the more comprehensive textbook Nondestructive Testing of Deep Foundations by Hertlein and Davis (2006).1.1 PurposeThe intent of this guideline is to provide practical guidance for the proper interpretation of NDT results on ACIP and DD piles. Short descriptions of the main integrity methods available are provided along with several examples of how to use all of the information available to make sound engineering judgments about the results. This publication is a state-of-the-practice guideline to promote accurate engineering evaluations.For engineers inexperienced with NDT, these guidelines provide sufficient background information on NDT methods to help understand the limitations of the testing, assess the results presented to them, and formulate appropriate questions. This is particularly important for engineers charged with the responsibility to determine from those results what, if any, consequences there may be on the performance of the structure under construction."

Jan 1, 2016

By Jhon Melo

Los “softwares de aplicación” como herramientas en la exploración geológica, generan importante información geográfica sobre el área a estudiar, así como la cartografía y la toma de muestras en laboratorio. En ese sentido, el presente texto señala el manejo adecuado de dichas herramientas a través del uso de una base de datos, donde existe una estructura basada en el software (VISUAL FOXPRO, PARADOX, etc) y asi ejecutarla mediante una aplicación gráfica que permita tener una representación de lo estudiado como ocurre en un muestreo geoquímico.

May 25, 1998

By CASSANDRA L. HOEBBEL, Jennica L. Bellanca

High-fidelity, immersive training is known for its learning and logistical benefits. While other industries have used virtual reality (VR) for decades, the same uptake has not been seen in mining. NIOSH recently developed an adaptable, scalable VR training platform, VR Mine Rescue Training (VR-MRT), which has attracted significant industry interest. NIOSH is using VR-MRT to understand the barriers to adoption and implementation of VR. As a part of a larger effort to assess the effectiveness and implementation of VR-MRT, researchers have conducted pre-implementation interviews. In this paper, the authors use feedback from individuals at various implementation levels to assess the acceptability and appropriateness of VR-MRT and identify potential implementation barriers for VR more generally. Researchers also describe ongoing efforts to overcome these barriers as NIOSH works to position VR-MRT as a supplemental resource more generally for mine safety training.

Feb 1, 2025

By M. F. Goudge

LIMESTONE surpasses any other rock or mineral in the number and diversity of its uses and in the quantity consumed fur industrial purposes. Either in the raw state or when calcined to lime it enters directly or indirectly into the manufacture of a great variety of products and its sphere of usefulness is continually expanding. The term "limestone" as here employed includes all varieties from high-calcium limestone, consisting almost entirely of the mineral calcite, to the highly magnesian variety, largely dolomite. Lime is also discussed .because lime is simply calcined limestone and often the material may be used in either the calcined or natural state. Limestone has been of service to man since prehistoric times but only in the last hundred years has it become one of the most important raw materials in industry. In every industrial country it comprises the greater part of the total stone produc-

Jan 1, 1937

By Robert Lee, Pertti Paavola

Automated vibration monitoring and web-based data distribution has proven itself on the largest single construction project ever undertaken in Finland. The excavation for the Kamppi Center Project in the center of Helsinki was completed in November of 2003 and involved the removal of over 200,000 m3 (260,000 yd3) of rock and over 1,700 individual blasts. A system was installed, incorporating 37 discrete monitoring points located throughout an underlying metro station, and other surrounding underground and surface facilities. After every blast, vibration data was automatically transferred from the monitoring network to a server database. Stakeholders were able to access and review vibration reports on a password-protected website within 90 seconds of each blast. This allowed engineers to verify that recorded levels were in compliance with established limits, before proceeding with subsequent blasts. The data was also imported into a semi-automated Scaled Distance tool for analysis using linear regression techniques. This was used to determine, and adjust for trends in blast-induced vibration.Copyright

Jan 1, 2004

This Bureau of Mines report and its companion report (Information Circular 9142) have been prepared to assist in the preparation of prefeasibility type estimates for capital and operating costs of beneficiation of various types of mineral occurrences using current technology. The handbook provides a convenient costing procedure based on the summation of the costs for the unit processes required in any particular mining or mineral processing operation. The costing handbook consists of a series of costing sections, each corresponding to a specific mineral processing unit process. Contained within each section is the methodology to estimate either the capital or operating cost for that unit process. The unit process sections may be used to generate, in January 1984 dollars, costs through the use of either costing curves or formulae representing the prevailing technology. The mineral processing handbook includes individual cost estimation sections for unit operations associated with comminution, beneficiation, solid-liquid separation, hydrometallurgy, and special applications as well as infrastructure and plant general and administrative costs. When using this system for estimating cost data for a mineral processing facility or for checking or verifying processing costs from an existing facility, a minimum amount of background information is necessary.

Jan 1, 1987

By M. J. Collins

"Autoclaves were first used in the metallurgical industry in 1893 to recover alumina from bauxite. In the 1940s and 1950s, several high temperature and pressure processes were invented in the laboratory of Professor Frank Forward at The University of British Columbia, in parallel with advances in equipment and processes by the Chemical Construction Corporation. Sherritt Gordon Mines Limited enlisted these groups to help develop the nickel sulfide ammonia leach process that was commercialized in 1954. Autoclave processes that have since been commercialized include high-pressure acid leaching of laterites, zinc pressure leaching, and pressure oxidation of refractory gold feedstocks. RÉSUMÉ En 1893, l’industrie métallurgique est la première à utiliser les autoclaves pour l’extraction de l’alumine dans la bauxite. Dans les années 1940 et 1950, plusieurs procédés à haute température et à haute pression sont inventés dans le laboratoire du Pr Frank Forward de l’université de la Colombie-Britannique (UBC) ; parallèlement, la Chemical Construction Corporation fait de grands progrès en matière d’équipement et de procédés. Sherritt Gordon Mines Limited fait appel à ces groupes pour qu’ils aident la société à développer le procédé de lixiviation du sulfure de nickel dans de l’ammoniaque, commercialisé en 1954. Les procédés de lixiviation en autoclave commercialisés depuis incluent notamment la lixiviation acide à haute pression de latérites, la lixiviation sous pression du zinc et l’oxydation sous pression des matières premières de l’or réfractaire.INTRODUCTION Autoclaves are chemical reactors that are built to contain processes taking place at elevated pressure. They are used in metallurgical refineries throughout the world to take advantage of the increased reaction kinetics and different reaction products that can be obtained in aqueous systems above the boiling temperature at atmospheric pressure. The word autoclave comes from the French “auto” and the Latin “clavis” and literally means self-locking—that is, the core distinguishing feature of an autoclave is that it includes a means for pressure regulation (e.g., a pressure relief valve). Denis Papin (Figure 1a), one of the inventors of the steam engine, was the first to make use of a safety valve to control steam pressure. He is credited with inventing the autoclave in 1679. Papin’s “digester” (Figure 1b) was a type of pressure cooker that was originally used to liquefy bones. Most commercial autoclaves are horizontal, multicompartment vessels with mechanical agitation, as shown in Figure 2a; however, the steam-agitated Pachuca vessels used to leach laterite ore in Moa, Cuba (Figure 2b), are also classified as autoclaves according to the self-locking definition provided above."

Jan 1, 2018

Jan 1, 1985

By J. F. Barkley

To reduce fuel consumption in industrial and commercial fuel-burning plants throughout the Nation, cooperative efforts of thousands of individuals are required. These individuals are scattered over the country and hold various positions in thousands of independent establishments. To accomplish as much as possible on this problem during the Second World War, it was decided that personal contact with fuel users was absolutely necessary; publicity, although an important factor, could not by itself give satisfactory and needed results. It was planned to have qualified engineers visit commercial establishments to go over with them the problem of reducing their fuel consumption. The specific plan, toward which all efforts aimed and around which the rest of the program revolved, consisted in brief of 1. Conference of visiting engineer with management to obtain cooperation. 2. Appointment by management of a plant employee as fuel "waste chaser." 3. Work of engineer with "waste chaser" and, if appropriate, with plant operators on most efficient operation of equipment.

Jan 1, 1948

Another major aluminum company announced intentions to follow other domestic producers recent price actions by raising its unalloyed ingot quotes by 3¢ to 44¢ per pound, effective June 1, 1976. COBALT: All final data for 1975 are included in the table for cobalt on page 23. Demand in March increased significantly for the second month in a row, signaling a recovery from the previous year's relatively low demand levels. Imports of cobalt tripled in March over those of February. This should partially offset reduced sales of cobalt excesses from the National Stockpile. Import projections for the next several months have been lowered because transportation difficulties in Zaire are expected to result in reduced shipments.

Jan 1, 1976

By George Hope, Brigitte Lacouture

"The Red Dog Mine has increased mill throughput for most years since startup. Although flotation equipment has been added over the last 10 years, the Red Dog metallurgical performance has been restricted by a lack of adequate flotation capacity. Two reduced tonnage trials conducted in 1997 as well as numerous SAG relines have consistently indicated the potential to significantly increase both zinc concentrate recovery and grade with additional flotation capacity. Late in 1999, a new circuit was designed with increased flotation capacity while simplifylng the current circuit, providing for three stages of dilution cleaning, and creating a retreat section. The purpose of the retreat section is to target the more complex particles and allow the chemical environment to be fine tuned for improved iron depression. In total, twentyone (21) Outokumpu OK50 mechanical flotation cells and four (4) 3.66m dia. column cells will be added to the current flotation circuit. The VIP (Value Improvement Program) Mill Optimization project is also addressing thickening, water treatment and power issues and has a total budget of $US105 M. Startup of equipment will be phased in to minimize the impact on current operations and is expected to be complete by the end of Q3-2001.INTRODUCTIONRed Dog Operations started production in November 1989. The mine is located above the arctic circle in northwest Alaska. It is linked by an 80 km road to a port-site facility where the concentrate is stored. Concentrate is shipped to markets throughout the world during the one hundred (100) days of open seas. Typical of sedimentary exhalative deposits, the metallurgy proved to be challenging and coupled with many mechanical shortcomings, the initial few years were very difficult. The start-up issues were slowly resolved and in 1998, a major grinding expansion, the PRI (Production Rate Increase) project, was completed. The project was designed to allow a 40% increase over the 1995 throughput. In 2000 mill throughput was 3,050,000 tonnes to produce a total of 960,000 and 140,000 dry tonnes of zinc and lead concentrates respectively, making Red Dog the largest zinc concentrate producer in the world. To address a shortage of flotation capacity remaining from the PRI grinding expansion, a project designated as the VIP (Value Improvement Program) Mill Optimization project was initiated. The mill optimization project is targeted to produce 1,100,000 tonnes of zinc concentrate at 56% zinc grade and 87% zinc recovery. The project will add twenty-one (21) Outokumpu OK50 (50m3) flotation cells, four (4) 3.66mO column cells and address water treatment, thickening and power generation capacities."

Jan 1, 2002

By Karl J. C. Harries

"5.1. INTRODUCTIONThis chapter is intended as a general overview of the subject of royalties between private parties – royalties extracted by governments are not dealt with. This same subject is covered in detail in Volume II, which critiques many sample provisions taken from agreements, giving both pros and cons. If you find something that interests you in this chapter, check Volume II for extra information. Detailed cross-referencing to Volume II has not been attempted, however, most subjects mentioned in this Chapter will also appear in Volume II, usually in greater detail. Reference should be made to the Index.A Brief History of Royalties1In the early days of mining in Canada, the tendency was to sell a claim for cash and to move on, using the stake to look for and stake more prospects. As prospectors became more sophisticated and Canada’s North opened up, the market for properties and the number of mining properties available increased dramatically. Speculation and the practice of consolidating several small properties into one large holding entity became common. In “hot” areas, the speculators2 could far outnumber the prospectors, many of the former having little or no prospecting expertise but lots of market and promotional savvy. However, to consolidate a number of small parcels into one large project can be expensive, and many of the parcel owners became interested in keeping a share in the project, rather than giving up everything. Speculators who were trying to consolidate small parcels wanted to minimize cash payments to parcel holders (usually they did not have much cash and preferred it flowing in their direction rather than away from them). Accordingly, non-cash transactions were developed to meet the aspirations of both owners and speculators."

Jan 1, 2003

By Tom Treleaven

The success of any blast is dependent on the accuracy of the blast design and the field controls used on the shot. This point cannot be over emphasized because when the geometry is not measured and/or field controls are not properly implemented, it can often have devastating effects on the final blast results. Thus drilling accuracy, tiont row burden control, explosive confinement, energy distribution, explosive selection, timing and structural geology become critical parameters in the design of successful blasts. Understanding the actual dynamics of the blast and why certain results were achieved is the fast step in optimizing a blast design. As stated by R. Frank Chiappetta, “Of all the blast monitoring systems available today, high speed videography still remains as the best stand alone instrumentation system for blast diagnostics.” Over the past years I have analyzed hundreds of blasts using either high-speed lowcams (500 frames per second) cameras or standard digital (30 frames per second). These analyses confirm, without a doubt, that shot geometry, in combination with structural geology, is the most important factor in overall blast results. Drilling accuracy is the single most important component in efficient blasting. Having equal mass associated with an equivalent energy is the basis in which blasts are designed. When drilling inaccuracy or borehole deviation occurs, not only is the energy unevenly distributed, but the basis of all design calculations becomes invalid. Over the past several years, quarry and mining operations have employed the use of boretracking measuring devices to measure borehole deviation and hole toe locations. In cases of operations using top hammer drills, it was discovered that the amount of deviation was significant and far greater than they believed they had. Set up error, improper drilling techniques and bit wear were some of the contributing factors. Through video anaysis of boretracked blasts, blast results were directly linked to drilling ..accuracy. The comparisons here took into account blast design, energy factors and hole sequencing.

Jan 1, 2000

By G. T. Lineberry

Underground mine development begins with the positive investment decision to mine and ends with the inception of full-scale exploitation. It incorporates all activities, personnel, and equipment required for creation of underground access to a mineral deposit. Because of the depletion of near-surface mineral resources, the reduced mobility of large surface mining equipment, increasingly stringent environmental constraints, and the introduction of promising innovations to rock penetration and rock excavating equipment (e.g., continuous miners, rock borers), under-ground mining is projected to account for an increased share of worldwide mineral production in the foreseeable future. Without proper engineering during the mine development phase, failure of the underground mining project is axiomatic. A frustration attendant to coverage of the complex area of underground mine development lies not only with the need for treatment of the many disparate specialties within the area but even with the lack of systematization of these specialties in what is recognized as a vital precursor to successful mining. Section17 offers insights into (1) the basic principles of the planning and design process, including baseline assessment, reserve determination, premine planning, and subsystem design (Chapter17.1); (2) equipment selection and sizing, with emphasis on exca-

Jan 1, 2008

This report presents information developed during Bureau of Mines contract H0242016, "Mine Shaft Fire and Smoke Protection Systems" from May, 1974 through June, 1975. Purpose of the metal and nonmetal health and safety project was to evaluate mine shaft fire and smoke hazard problems, and to develop and demonstrate a low-cost, reliable mine shaft fire protection system that would protect against such hazards and would be applicable to a majority of metal and nonmetal mine shafts, including raises and winzes, especially in deep mines. Program effort proceeded through five phases, culminating in the successful in-mine fire demonstration of a prototype system. In addition to this final report, a film is available which depicts components of the system and its successful shaft fire testing at an underground mine.

Jan 1, 1975

By W. G. Freeman

It is unlikely, as In the past, improvement in truck efficiency and capacity can fully offset the effects of inflation, fuel costs/shortages and ever increasing haul distances. There-fore, investigations of haulage systems less sensitive to these problems are warranted. Thus, this U.S.B.M. contract research study on alternative continuous haulage systems was prepared. This study identifies the physical, economic and technological parameters in the application of continuous haulage systems with special attention to under pit slope conveyors and skip hoisting systems. The evaluation data was gathered from extensive literature searches. European/North American mine visits, and industry comments. The study concludes that continuous underground haulage is a viable method within the proper geometric configuration.

Jan 1, 1978

By S. Stoyanov, M. Cross

"Silicon components containing transistor circuitry are at the heart of electronic products such as computers, mobile phones, etc. These components are connected to printed circuit boards (PCB's) using solder material that acts as the conductor for both electricity and heat. During the lifetime of a product it will undergo many thermal cycles where the chip becomes hot during product operation and then cools when the product is switched off. At the product design stage engineers undertake thermo-mechanical simulations to predict the thermal stress in the solder joints due to this thermal cycle and to ensure that the stress magnitude will not result in early fatigue-type failure. The design engineer's aim is to identify component parameters which ensure that the solder will survive beyond a certain number of thermal cycles.The aim of integrating computational mechanics and optimization tools together is to speed up dramatically the design process. From viewpoint of a design engineer in the electronics manufacturing sector, these tools can be used to quickly estimate key design parameters (i.e. material properties, product dimensions, etc) that will guarantee the required product performance. In this paper a modeling approach coupling computational mechanics techniques with numerical optimization is presented and demonstrated. The integrated modeling framework is obtained by coupling the multi-physics framework - PHYSICA - with the design optimisation tool- VisuaLDOC. Thermo-mechanical simulations are presented that predict the creep strains in solder material. Different numerical optimization procedures: Direct and Response Surface based optimization plus Design of Experiments, are tested as a part of this modeling framework."

Jan 1, 2001

By William G. Fischer

This paper attempts to close the gap between extensive rock testing with field measurements and the mine operator's need for safe mine layouts and alternatives. It was found that many of the variables that influence mine geometry and worker safety are relatively unimportant while others are critical. The development of empirical relationships which tie the critical variables to the "safe useful life" of a trona mine layout and observations made in 140 production areas where the variables were researched over a fifteen year period are discussed. The concepts presented may have applicability in mine design for other bedded deposits.

Jan 1, 1984

By W. J. Atkinson

The first recorded discovery of diamonds in Australia was in 1851 in New South Wales. Subsequent prospecting has shown alluvial occurrences of diamond to be widespread through much of the Tasman fold belts of Eastern Australia. Production is estimated to be some 500,000 carats from several small alluvial fields. Despite extensive exploration, though, no primary rock source carrying significant diamond content has ever been confirmed in Eastern Australia. Conversely, diamond exploration of the older Western and Central Cratons of Australia during the past 30 years has discovered 12 fields containing 360 kimberlites, lamproites and lamprophyric volcanic pipes, dykes and other intrusives. Of those, 180 have been confirmed to be diamondiferous. Only one pipe, however, the 1200 Ma high-grade Argyle lamproite and associated nearby alluvials, has proved to be economically exploitable. Its current annual production is 40 million carats valued at about US$400 million. Production from the open pit will be sustainable until at least 2003.

Jan 1, 1995

By David L. Borusiewicz, M. Suri Surendra

"Abstract Helical piles have been used as anchors and for supporting lightly loaded structures as a method of underpinning, etc in the past. Recently, helical piles are being used to support new structures because of their simple installation process using relatively light and mobile equipment. This paper presents the results of evaluation and design performed for the temporary support of existing piers during a bridge rehabilitation project.INTRODUCTIONThe helical screw foundation was invented and patented by Alexander Mitchell in England in 1833. He installed screw piles to support lighthouses in the tidal basins of England. Many applications in the earlier years in the USA were in North Carolina and in Florida to support lighthouses (in coastal plain deposits). A lighthouse of similar foundation design is still in use at Key Biscayne, Florida.In the USA, the helical piles were reintroduced as foundation elements for electrical transmission towers. Helical piles were also used for anchoring guys of self supported towers and as tie-backs for excavation support systems. Typically, helical piles are being used for supporting lightly loaded buildings and for underpinning buildings undergoing distress as a means of remediation. The helical piles are not commonly used in the transportation industry.HELICAL PILESHelical pile is a segmented deep foundation system with helical bearing plates welded to a central steel shaft. Load is transferred from the shaft to the soil through these bearing plates. Central steel shafts are available in either a square shaft (Type SS) or a round shaft (Type RS). The Type SS series are available in 38 mm to 57 mm square sizes. The Type RS series are available in 73 mm to 114 mm diameter sizes. Type SS-RS combinations are also available for compression applications in soil conditions where dense/hard soils must be penetrated with softer/loose soils above the bearing strata.The leading segment consists of a shaft with one or more helical plates that are welded to the shaft. The plates vary in diameter from 203 mm to 355.5 mm and have a thickness of 9.5 mm or 13.7 mm. Typically the plate diameter increases from the bottom of the shaft upward. A helical bearing plate or helix is one pitch of a screw thread. All helices, regardless of their diameter, have a standard 76 mm pitch. Being a true helical shape, the helices do not auger into the soil but rather screw into it with minimal soil disturbance. Helical plates are generally spaced a distance of two to three times the diameter of the plate directly below in order for them to function independently as individual bearing elements. A typical detail of helical pile is shown on Figure 1."

Jan 1, 2014