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By M. Kumaran, A. Vetriselvan, A. Purantharan

"This paper presents a case history of evaluating the stability of a distressed earth bund and rectification measures carried out. A 5.45 km long, 7m high earth bund for drinking water storage was constructed in Andhra Pradesh. During construction of the bund following were observed – (a) a longitudinal crack at the downstream side (b) Bund on the downstream side along the crack settled to a max of 700 mm and (c) downstream rock toe level area raised by heave up to 175 mm. Investigation of the events made important contributions to the fundamental understanding of the behaviour of large earthworks of this type. It was found that the variation in subsoil strata was not addressed during the execution.After careful evaluation, stone columns were recommended as a suitable ground improvement technique. Stone columns were used as a reinforcement to improve the shearing resistance of foundation and in turn ensure stability. By using and applying advanced geotechnical engineering analysis tools and modelling techniques, earth bund and its foundation was analysed and examined against failure by slope instability. Stone column design was carried out using in-house computer program GEOSTONECOL and stability of earth bund was analysed using TALREN software. Earth bund construction was completed after ground improvement and is performing satisfactorily.INTRODUCTIONIn order to supply water during summer season, Government of Andhra Pradesh decided to construct a 7m high and 5.45km long earth bund summer storage tank. It was one of the largest earth bund summer storage tanks in whole of South India at the time of its construction. During construction, the earth bund has undergone sudden distresses. Investigation of the series of events occurred during construction has made important contributions to the fundamental understanding of the behaviour of large earthworks of this type. This paper presents the reasons for earth bund failure, slope stability assessment of the distressed earth bund and recommendation of stone column as a suitable ground improvement remediation technique.DESCRIPTION OF STUDY SITEThe characteristics of the original construction are briefly described as follows. A shallow cut-off trench was excavated below existing ground level at the centreline of bund as shown in Fig. 1. Below the base of the trench a cut-off grout curtain was installed. Upstream and downstream shell earth filling was carried out using Clayey Sand ‘SC’ type soil. At some locations, bottom of cut-off trench has reached as deep as 12m from the existing ground level."

Jan 1, 2017

To develop a conceptual design for an automated longwall mining system, one should know what has been done, what is being done today and what is being planned for tomorrow. The bibliography referenced and discussed in this report provides a good source for that knowledge. To scientifically determine where attention should be focused to up-grade a system, the system must be quantized as far as possible. The Mechanization Profile of Appendix A-I is discussed in this report and has been used to analyze and determine the degree of mechanization currently in use and/or described in the literature for all three major elements of the long-wall system, namely, Winning, Roof Support and Haulage. The charted profiles make it self-evident where attention and design effort is needed to remove human operators from the face of the mine.

Jan 1, 1975

By Paul. D. Merica

I LIKE to look upon the award this year also as a recognition of the importance of metallic materials of construction to the engineer and of the active progress which I believe is continually being made in almost all branches of that field today. It has been said that metals are the material backbone of industry and technology. Well in that case, I suppose we metallurgists are industry's bonesetters. And it is possibly not inappropriate that we should occasionally give some atten¬tion to those bony structures of our industrial activities upon which engineers in other fields hang their manifold and striking creations. What is going on in the field of metals development? Well, in the first

Jan 1, 1938

By R. Melley, P. Wissner

The paper looks at the basic theory of tri-bological wear and the role played by the lubricant and its additives. It presents the argument that the “real cost of lubrication” is not the purchase price of the oil or grease, but rather the costs associated with not using the correct lubricant. A number of examples are presented, covering oils, greases and additives, in which a detailed evaluation of the application has shown that when all of the benefits of using the best lubricant/additive are evaluated, the savings achievable greatly surpass the incremental cost of the superior lubricant. One of the emerging classifications of costs in industry today are those associated with environmental protection. Two of the examples used describe the replacement of more conventional lubricants with environmentally acceptable products, compounded to compete in all aspects of serviceability, but which have the added bonus of being not only biodegradable but also of being of low toxicity.

Jan 1, 1997

By Eugene McAuliffe

In the year 1581, the counselors of King Philip of Spain suggested to that monarch that a canal across the Isthmus of Darien would open the west coast of the South American continent to Spanish miners and explorers, enlarging and expanding the flow of precious metals then just beginning to trickle across the path cut by Spanish Conquistadors, from old Panama to Puerto Bello on the east coast. The King sent out a party of surveyors and explorers under the command of a young engineer, Savadaerro, who returned after two years, reporting upon a location for a canal which was virtually adopted by the French engineers employed by De Lesseps, who in 1877 commenced the work of constructing the Panama Canal-296 years after Sava- daerro's first survey was begun. The suggestion for an Isthmian canal, made to the king at a time when Spain was a proud, virile nation and when that country was contending with England in the fields of discovery and conquest, represents a measure of vision that has never failed to intrigue the imagination. That the young Spanish engineer recommended an undertaking so gigantic in conception that it took three and one-third centuries for its completion from the time it was first visioned matters little. In the day of Philip of Spain,

Jan 1, 1932

By Jacob W. Young

A casual reading of the geological literature extant to-day would give one the impression that carbon is an element which by some chance or another always existed at or near the surface of the earth, and was never of a magmatic origin. The carbonaceous matter in shales is said to be of vegetal derivation; petroleum is stated to have been derived from vegetable matter or from marine animal bodies; if carbon or bituminous matter is found in igneous rocks or associated with metallic ores, the statement is made that deeply buried carbonaceous sedimentaries were undoubtedly the source from which such carbon or bituminous matter was derived. This, I do not consider a reasonable or common sense view of the matter. Carbon is one of the elements of which the earth is composed. In the table giving the periodicity of the elements it comes sixth in the order of increasing atomic weights. It is an element formed like all the rest were formed, and must be as common to the interior of the earth as the rest of the eighty-odd elements so far discovered. The spectroscopic analysis of light from the sun, and the stars, shows the presence of carbon in the sun and in the colder stars. Thus with carbon, an element, found throughout the universe as well as on the earth, it is entirely reasonable to consider it as present in the interior of the earth with the other elements. Such being the case, the magmatic origin for the various forms of carbon in rocks and ores is a rational and logical conclusion. If but a small fraction of thought and effort was made along these lines, which is made in fostering the idea of the organic origin of the carbon found in the earth's crust, untold advances in this phase of geological science would result.

Jan 1, 1925

By S. Schade, G. Möllemann, C. Niestroj

"Mining environments, whether open-pit or underground, pose difficult conditions for any sensor system. However, the ever-increasing need for automation requires the application and use of sensor systems in order to gather relevant information required for process automation. Ultra-Wideband radio (UWB) is a robust technology well-suited for underground applications. These applications include positioning and communication. This paper introduces UWB and presents results from measurement campaigns in harsh environments. Using filtering and sensor fusion precise and robust positioning can be achieved even in confinements of underground mining environments. INTRODUCTION Indoor positioning systems (IPS) are gaining ever more importance. Especially in light of ongoing efforts to reach the goals of what was coined as Industry 4.0 by the German government, the development of IPS is inevitable. According to a recent report about the “Global Indoor Location Market Outlook 2019” a growth from $ 597 million in 2014 to $ 3961.8 million by 2019 is expected [1]. Hence, there is also an economic incentive to pursue this topic. The mining industry is profiting from this development as well, since IPS are the basis for the automation of especially mobile mining equipment. Ideally, indoor positioning systems offer to position the equipment continuously and, what’s more, even in real-time [2]. Different approaches are available for IPS. The difference of these systems lie in terms of accuracy, cost, precision, technology, scalability, robustness and security. [3] At the Institute of Advanced Mining Technologies (AMT) of RWTH Aachen University, research suggests that one of the more auspicious approaches for IPS in the mining sector is the employment of ultra-wideband (UWB) radio technology. Because of this, there has been ongoing research into the best way to introduce UWB technology for the application in underground environments. The research started with an indoor positioning application, which only consisted of the UWB system. In the course of this, different algorithms were developed to enhance the system’s performance for the use in the mining industry. This led to the idea of sensor fusion in which the information of the UWB system are combined with infrastructure-independent technologies like inertial navigation systems (INS) and image-based technologies."

Jan 1, 2017

By Alberto Ríos Carranza

El presente texto describe la evolución de la cuenca Lancones (Piura) y sus estilos de mineralización en la búsqueda de yacimientos vulcogénicos de sulfuros masivos. Dada las características de la cuenca es considerada el principal objetivo en la prospección de yacimientos vulcagénicos de sulfuros masivos. Así también se revisa el contexto geotécnico, geológico, metalogenia, depósitos magmáticos - hidrometales, tipo Skarn, y vetiformes, estratigrafía y modelo metalogénico.

May 1, 2016

By T. R. Ellis

Considerable movement is afoot internationally to rationalize standards and regulations relating to valuations and the qualifications for valuation professionals. In July 2000 the International Valuation Standards Committee released expanded standards, and additional important improvements are planned by 2003. Possible updates to the International Accounting Standards (IAS) and potential adoption of IAS by the U.S. could significantly impact minerals appraisers. Standards designed specifically for mineral asset valuation are under development in Canada and the U.S., with Australia’s internationally respected VALMIN Code providing the benchmark. In the U.S., the all-encompassing Uniform Standards of Professional Appraisal Practice (USPAP) is annually modified and continues to gain deeper acceptance, while the SEC holds fast to its antiquated rule prohibiting reporting of a quantitative estimate and value for non-reserve mineralization. Some important international trade agreements are driving actions to free the trade in professional services. In July 2000, an international workshop was held to initiate discussion on minimum qualifications for appraisers to work internationally. Pressure for uniform minimum qualifications and rules for professionals internationally will continue to build. The U.S. is historically among the slowest countries to implement such initiatives, with its state level licensure barriers having the potential to cause some of its professionals to be stranded in an international backwater. Structural change is needed in Australia’s VALMIN Code to remove conflict with the latest International Valuation Standards. The mineral valuation standards developers of Australia, Canada and the U.S. should work jointly on updating VALMIN for global use.

Jan 1, 2001

By I M. Turnbull

QMAP (the Quarter Million Mapping Programme, 1:250 000 scale) is a geological mapping programme which will build a digital geological database of the whole country and publish maps and books to document it. The programme was established in 1993, following a recommendation by a review panel appointed by the Ministry of Research, Science & Technology, and is funded by the government, from the Public Good Science Fund. The relevance and fundamental value of QMAP lies in the greatly improved geological knowledge it will provide for researchers and other end-users of geological information.   QMAP research involves assessment of previous work, field and laboratory investigations in key areas, and data storage, manipulation and publication using Geographic Information Systems (GIS) computer technology. The QMAP digital database of New Zealand geology will be completed by 2006, as will the series of 21 full colour printed geological maps and accompanying explanatory texts. Two are already completed and published (Kaitaia and Dunedin), and six other projects are well advanced.   QMAP information will also be available in digital form. Next year we hope to expand the scope of the programme to cover the reconciling and linking of many other earth science databases to QMAP, because we believe this will create a powerful research tool. The intention is to develop internet access to the databases, to make the information publicly available.

Jan 1, 1997

By Donald Koch

The project investigated regional impacts of mining on the ground water system of the Powder River Basin by: 1) establishment of a regional ground water monitoring network, and 2)development of , set of digital computer models to simulate ground water flow and quality, ground water contributions to surface water flow and quality (i.e., baseflow), and watershed run-off and recharge. Over 100 wells were monitored for physical and chemical parameters. Data were used as input to the model; and for the development of a comprehensive data base. The basin was modeled on a regional and subregional scale using a finite -difference model employing an alternating difference technique. Two water-shed models were evaluated for their ability to provide runoff and recharge inputs to the basic ground water model. Application of the regional and subregional models using conservative mining scenarios showed that drawdowns may extend west from the mines as far as ten miles but that impacts would be insignificant on a regional scale. The watershed model could be effectively applied to small watersheds only.

Jan 1, 1982

By Zay Jeffries

From the title of this chapter the reader could expect an attempt to outline the anticipated shape of things to come, mineralwise. We have no crystal ball and if we possessed one we could claim no expertness in its use. In the first place no one can tell the future status of man. No one has any way of knowing to what extent peace will prevail, nor to what extent changes may occur in national sovereignties or forms of government or in international relationships. So future man is an uncertainty. Nor can we predict new developments that may result in significant changes in man's status or in the mineral industry or both. If, for example, this chapter had been written in the middle 1930's, nearly everything that has happened since in the field of atomic energy would have been missed. Yet what a vast change this has made in the status of man! Also the changes in the mineral industry have been important. A writer would have been bold indeed had he prophesied that uranium would play such an important role. But we need not confine our foggy vision to the atomic energy field. The steep rise in the use of aluminum, titanium, and germanium reflects the unpredictable in what may be thought of as the more normal pursuits. This should not discourage one from using the past and currently observable trends as bases for limited predictions. To do this, however, it is desirable to make certain assumptions about man's status without even a pretense that these assumptions have a high probability of fulfillment: 1. Only minor changes will occur in the geographical boundaries of the nations of the world. 2. World War III will not take place in the near future. 3. As a consequence of (2), man will not destroy himself by wanton use of atomic weapons. 4. Disarmament will take place, if at all, gradually rather than all at one time. Under the above assumptions the world will enjoy a period of relative peace even though the status may be one of an armed truce. The assump-

Jan 1, 1959

By Y Yang

This paper discusses various issues surrounding the metallurgical control for furnaces, especially focusing on processes with long time-constants and æmetallurgical memoriesÆ. Examples will focus on furnaces accepting particulate and sometimes ill-defined feeds, eg submerged-arc furnaces, blast furnaces, secondary scrap smelting operations, recycling operations, waste incinerators, etc. Generally, because of the usually higher metallurgical time constant of these furnaces, these reactors have to be controlled in a feed-forward manner by the use of a hybrid of æblack boxÆ or empirical and ægrey boxÆ semi-empirical first principles metallurgical modelling and simulation techniques in a supervisory metallurgical control capacity.

Jan 1, 2000

The purpose of this study was to examine the problems of underground coal mining in the United States, and to develop recommendations for an integrated Research and Development Program aimed at resolving these problems. Specific objectives of the study were as follows: ? To identify the existing inadequacies that have adverse effect on Health, Safety, External Environment, and Productivity. ? To identify opportunities for technological advance s to correct these inadequacies. ? To develop an integrated Research and Development Program designed to accomplish the advances identified. Many of the recommended tasks are dearly long range; this is especially true of those for study of future mining systems. However, funding recommendations in this Report are presented for a 5 -year period, since the developments accomplished during this period will undoubtedly be a factor in the formulation of the follow on tasks. Where applicable, the recommended Research and :Development could include development and test of pilot model equipment.

Jan 1, 1970

By Glenn Norris, Tyler Buckingham

"Gold recovery gains in the order of one to two percent have been realized in 2009 due to changes in the operation of the grinding circuits at Barrick Gold Corporation’s Hemlo - Williams Mill. The initiative known as “split milling” involves milling low grade open pit ore in one grinding circuit and higher grade underground ore in the other grinding circuit under different conditions.The philosophy of split milling involves processing higher grade underground ore at a lower throughput rate and a finer grind while milling lower grade open pit ore at a higher throughput rate and a coarser grind. Bench scale tests showed that the recovery relationship for underground ore sources was much more grind sensitive than that of open pit ore. This relationship proved to hold in the plant. The gold recovery gain due to finer grinding of the higher grade ore is much greater than the recovery loss due to coarser grinding on the lower grade ore. Since the majority of gold is being recovered at a higher rate, this results in higher overall plant gold recovery when compared to the traditional operation philosophy of blending the ore sources.The challenges for achieving the maximum benefits of split milling were two fold; the need to increase throughput on the open pit ore milling circuit and a means of grinding finer on the underground circuit. The former was met with an increase in SAG (Semi-Autogenous Grinding) mill ball charge, a basic “drill to mill” blasting campaign and changes to the primary gyratory crusher. The latter was met with a reduced SAG mill ball charge and a higher milling density. The resulting benefits in additional gold recovered are in the order of $3-5 million per annum.INTRODUCTIONThe Williams Mill processes ore from three different ore sources, the David Bell Mine (DB), the Williams Underground Mine (WUG) and the Williams Open Pit (OP). All three ore sources are located within the Hemlo camp in Northwestern Ontario adjacent to the Trans-Canada Highway. The Williams Mill was built in the mid 1980’s at which time it was designed to process 3,000 dry metric tonnes per day through a 22’ SAG mill in series with a 16’ ball mill. In 1988 a Mill expansion doubled the mill capacity by adding a second identical grinding circuit. A photo of the current grinding circuit can be seen in Figure 1. Today the Williams Mill processes an average of 8,000 tonnes per day of which approximately 60% is from the Williams Open Pit."

Jan 1, 2010

By María del Rosario González Moradas

El presente texto describe diversas técnicas de teledección como métodos para determinar alguna de las variables utilizadas desde el punto de vista geotécnico y que permiten una clasificación de los macizos rocosos. La metodología se ha basado en la búsqueda de las bandas más ventajosas a las combinaciones más adecuadas para la determinación de cada una de las variables geotécnicas citadas a través de las imágenes landsat 5 de dos épocas diferentes.

May 1, 2017

By Jean-Marie Fecteau

The gold mine sector is presently facing low gold prices as well as technological challenges. Its competitiveness and survival will depend on new mining methods and equipment to improve ore extraction. In 1999, Natural Resources Canada has invested new funds over a period of three years at CANMET?s Experimental Mine to establish the Narrow-Vein Mining Project. A team of engineers and researchers specialised in mining, mechanics and electronics engineering are working to meet the critical need of ore-extraction technology. CANMET?s program in mechanisation and automation for narrow vein mining had, prior to 1999, realised several important achievements, many in co-operation with a consortium of mining companies (Soredem). The investment of new funds in this area will contribute to develop technologies to improve the productivity, as well as health and safety conditions of the narrow vein mining industry. Several important impacts of this project will be monitored. Specifically, a database of methods and equipment used in narrow vein mining is being developed. A key thrust is to identify operators? needs with respect to the development and automation of mining methods and equipment. Based on those needs, research and development projects will be created. The main problems identified following meetings with mine operators are described with a few elements of solution and the Web site created for the broadcast of the results is presented.

Oct 1, 2001

By Daniel I. Carey

Current and potential dragline reclamation usage was evaluated for the U.S. coalfields based on data gathered and analyzed during field surveys, literature reviews and contacts with manufacturers. It was concluded that current wining plans have been adapted to federal and state strip mine and reclamation laws in ways which limit the potential for drag line reclamation systems at active mine sites. At abandoned conventional contour mine sites in steep-sloping areas such as central Appalachia, however, it was found that dragline reclamation systems have great potential application and may be the only practical solution to many reclamation problems. Alternative dragline systems were examined for restoring abandoned sites, and it was concluded that a tower excavator system offered superior characteristics and should be evaluated and developed under field conditions. A testing program was developed to provide a framework for the monitoring and analysis of cost, production and environmental data during a field demonstration of a tower excavator system.

Jan 1, 1981

This paper presents the near-field rock damage owing to production blasting in limestone quarry in the western region of Japan. The study's purpose is to learn the mechanism of crack development due to blast vibration. In this study, blast vibration's magnitude was expressed with peak particle velocity (PPV) which was obtained based on seismographs recorded database. In attempt to pursue a research's purpose of this study, there were two considerable interests: near-field blast vibration propagation and prediction, and crack observed and prediction. Furthermore, with regards to considerable interest of the study, there were three essential aspects which were challenged, such as: monitoring and interpretation of seismic wave propagation in a rock mass near large explosive charge of production blast scale, measurement of blast rock damage in adjacent to blasthole, and determine critical value of PPV which may produce significant rock damage. In order to determine precision critical PPV, understanding correlation between rock damage with vibration level is firstly important to be done. This paper also discusses how to measure, detect and quantify near-field blast vibration and blast rock damage in adjacent to blasthole.

Dec 6, 2010

By Iván E, Alex Araya Jofre, Jean Guiroux Toro, Eduardo Valdés Guerra

Currently, it is important for companies to have controlled mining operations and adhere to production schedules. To achieve this, one of the key factors is maintaining high reliability in the P&T process, primarily the opening of ore stope, which could be delayed due to any unplanned or uncontrolled problem. These ore stope opening processes, whose main activity is generating free face, are a very important pillar for future mine planning. The possibility of ensuring their opening brings a series of downstream benefits: safety, economics, productivity, and compliance and adherence to plans. The process under discussion consists of developing free faces in a single blasting event. This will help us leverage greater reliability for overall production operation plans, reduce construction times, and open up opportunities for downstream improvements in the production process, considering technical factors in P&T designs. This study presents a developed methodology and shows the results of its implementation in ten (18) single-event free face blasts. The analysis includes cavity geometry, geology, rock qualities, drilling deviations, and the blasting strategy implemented for each event. The methodology used considered material fluffing processes, the actual drilling trajectory, the initiation sequence, QA/QC during explosive loading, monitoring instrumentation (vibrations), and VOD recording, among others. As a result, out of a total of 18 free-face events blasts in a single event, 16 were successful and two achieved 90% efficiency, reducing the stope's production start-up time by 50% compared to current operations. By implementing free face blasting in a single event, there are savings in operating costs, increased productivity of the mining equipment, and improved adherence to production plans. For applications with greater heights of free faces, where blasting cannot be carried out in a single event, we should consider performing them in two stages using wireless detonators already available on the market for mining operations.

Jan 26, 2026