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By John P. Turner, Steven S. Dapp, Dan A. Brown

"The Goethals Bridge Replacement (GBR) spanning the Arthur Kill Waterway between Elizabeth, NJ and Staten Island, NY is supported on over 200 drilled shaft foundations ranging in diameter from 4.5 ft to 10 ft and socketed into Passaic Formation siltstone. Four drilled shafts, two on each side of the bridge (NJ and NY), were load tested using the bi-directional axial load method. Axial test results demonstrate that RQD, taken by itself, is not necessarily a reliable indicator of side or base resistance. High recovery with low RQD can be a function of horizontally bedded siltstone and shale where the individual pieces of core do not exceed four inches, but may still provide very high side and base resistance. Axial testing was followed by a lateral rapid-load test (Statnamic) on each of the same four shafts. In addition, one of the shafts was subjected to a static lateral load test to validate the rapid-load method as being representative of static loading conditions. Results of the axial load tests provide the basis of unit side and unit base resistances used in the LRFD design of the rock sockets for axial loading, while results of the static and Statnamic lateral load tests were used to calibrate p-y curve parameters used for design under lateral and moment loading. This paper describes implementation of the load testing program and its role in the design process.INTRODUCTIONDesign of drilled shaft foundations for the Goethals Bridge Replacement (GBR) required load testing in order to validate the parameters used for calculating geotechnical axial and lateral resistances. The bridge, including foundations, was designed in accordance with the AASHTO LRFD design specifications, 6th Edition (2012). The bridge owner is the Port Authority of New York and New Jersey (PANYNJ). One of the PANYNJ project requirements was stated as follows:“Perform a minimum of two (2) separate axial compression load tests (one [1] in New York and one [1] in New Jersey) for each demonstration shaft of different size and construction methodology to verify the design assumptions and construction procedures. At a minimum, one (1) demonstration shaft is required to be representative of production shafts with a diameter within one (1) foot above or below the demonstration shaft diameter.Conduct a minimum of two (2) lateral load tests (one [1] in New York and one [1] in New Jersey) for each demonstration shaft of different size and construction methodology. At a minimum, one (1) demonstration shaft is required to be representative of production shafts with a diameter within one (1) foot above or below the demonstration shaft diameter.”"

Jan 1, 2016

By A. Sokolov, E. Hasikova, V. Gostilo, V. Titov

Introducing online X-ray fluorescence (XRF) analyzers in the mining and processing industries can lower costs and improve the representativeness and speed of analysis. The applicability of the CON-XTM industrial conveyor XRF analyzer for continuous measurement of potassium content in process materials was demonstrated at various stages of potassium muriate (MOP) production. The CON-X analyzer produced reliable and accurate results for sylvinite ore (27–36% KCl), MOP cake after flotation (88–97% KCl), and NaCl residue (1.5–5% KCl). Tests of the analyzer at an MOP-producing plant showed a < 0.5% difference between online and laboratory results.

Jan 1, 2014

By Brian P. Atkin

The NISOMI-81 opaque mineral searcil and identification system uses quantitative color values (Pe, dA, y) and VHN as its determinative para-meters. The system is designed to operate on a Radio-Shack TRS-80 micro-computer which is interfaced to a motorised diffraction grating mono-chromator (WILSCAN). Using an interfaced monochromator/photometer combination a typical identification including the measurement of the photometer data on both specimen and standard, calculation of color values and a computer search takes about 6 minutes. The data file contains 240 minerals at present but can easily be expanded as reliable new data become available.

Jan 1, 1982

By D. R. Derry

"IT WOULD TAKE a braver man than I to try to forecast the future of mining exploration far into Canada's second century. Even to look ahead ten or twenty-five years we must review the figures of the fairly recent past -and I have found this quite a time-consuming but interesting job -in order to find trends and project them into future years. The trends to which I will refer are: firstly, the annual expenditure on exploration and its relation to value of output; secondly, the discovery rate and its relation to production initiations; and thirdly, the methods by which discoveries have been, and will be, made. Exploration Expenditures Figures on the annual expenditure on mining exploration in Canada have been collected and published for some years by the Do-minion Bureau of Statistics. These have some unavoidable limitations; e.g., in the varying definition between one company and another of what comprises ""Exploration"" and in the difficulty of getting complete returns. However, although the actual figure for a given year may be subject to question, I believe that the relative figures from one year to another are reasonably reliable. There is also a lapse of time between the collection of data and publication -the last published figures are for the year 1963. In bringing the figures up to date to 1966 I have canvassed eight of the larger mining and exploration companies and obtained their figures for 1963 to 1966 inclusive, and then averaged these for each year and applied the progression to the 1963 figures."

Jan 1, 1968

By N Gupta, R Trivedi, S Bhandari

Managing blasting operations in four mines surrounded by villages is a challenging task. This study aims to compare the blast-induced flyrock as observed in opencast mines by predicting flyrock distance using a soft computing approach known as an adaptive neuro-fuzzy inference system (ANFIS) and Flyrock Predictor software based on empirical studies. Blast design and geotechnical variables such as linear charge concentration, burden, stemming length, specific charge, unconfined compressive strength and rock quality designation were selected as independent variables, while flyrock distance was used as a dependent variable. Out of 120 blasts, data from 100 blasts was used to train and test the ANFIS model. Flyrock distance for the remaining 20 blasts was used to evaluate the model. Flyrock distance has also been predicted using Flyrock Predictor software based on an empirical approach using the same data sets as those used for ANFIS. Performance indices like root mean square error (RMSE), mean absolute error and coefficient of determination (R2) were evaluated to compare the reliability of ANFIS and Flyrock Predictor quantitatively. ANFIS was found to be a better predictive tool, with 1.75 m RMSE and 0.966 R2 compared to Flyrock Predictor, which returned RMSE and R2 values of 2.48 m and 0.932 respectively.CITATION:Trivedi, R, Singh, T N, Gupta, N and Bhandari, S, 2015. Soft computing approach to predict blast-induced flyrock, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 455–462 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By T. Gerritsen, R. MacRosty, R. Pula, P. Gebski, W. L. Ying

Furnace run-outs can cause extended furnace downtime for repair, while leaks or more severe failures in the cooling system can lead to brick hydration or in severe cases, steam explosions. These incidents can result in lost production, damage to equipment, injuries and casualties. To prevent such incidents, reliable and accurate techniques to monitor the critical components of the furnace such as refractory lining, furnace structure, taphole integrity and main water circuits are required. This paper describes several advanced methods that have been developed to assess the condition of furnace integrity, refractory lining, tapholes and cooling water circuits.

Jan 1, 2015

By M. R. Baren

Unpublished results obtained by Baren on thermodynamic properties of sulfur in liquid Fe. Co. Ni. Fe-Co. Fe-Ni. and Co-Ni are reevaluated. correlated. and interpreted on the basis of recent developments in thermodynamics of alloys:. Existing reliable data are reviewed and compared with the? present results. Sulfur obeys Henry&apos;s law up to 0.04 mol fraction. and in this range the standard Gibbs energy of solution of sulfur is expressed as a linear function of temperature for each pure metal. The activity coefficient of sulfur in each binary metal solvent 1s correlated with the composition of alloy.

Jan 1, 1983

By G. R. Webber, L. M. Azzaria

"The wide interest in the application of the geochemistry of mercury to mineral exploration is leading to the continued development of a variety of analytical methods for the determination of nanogram quantities of this element. The various methods have different degrees of reliability, sophistication and portability. In this investigation, two simple portable instruments were used in geochemical prospecting surveys -an ultra-violet absorption instrument and a similar one modified with gold for the removal of interfering substances. The results show the application of the method to the determination of mercury in soils of different organic content, and in rocks, sulphides and air."

Jan 1, 1969

By M. R. Yenchek

The U.S. Bureau of Mines designed and constructed sensitive and coordination-free ground-fault relays (GFR&apos;s) for use on mine power systems. First, a list of GFR attributes for mine ac utilization applications was compiled. These practical guidelines specified design, construction, transient immunity, reliability, and operating criteria. The time-current characteristics of the ac and dc units, subsequently fabricated, were designed to be below the human electrocution threshold. The significant and highly variable capacitance of high-voltage distribution cables was found to preclude the sensing of ground currents in the milliampere range. However, the coordination-free system developed for high-voltage distribution should enhance safety by significantly decreasing response time to ground faults. Implementation of the sensitive GFR technology in the mining industry has the potential to eliminate the majority of injuries and nearly all the deaths resulting from contact with energized components.

Jan 1, 1990

By O. Lashkari

Manipulation of pouring temperature is an efficient way to produce different microstructural features. In order to characterize the microstructure of rheocast billets due to different superheats of 615-695 °C, the parallel plate compression method was employed. Foundry 356 Al-Si alloy with different morphologies of primary a-Al particles were tested at different initial pressures of 4,8, 11,2 KPa, The resulted strain-time graphs were further treated mathematically to calculate viscosity of SSM billets. The interrelationships of viscosity, the microstructure and primary phase flow during compression are discussed, It is shown that the dendritic primary a-Al structure has the highest viscosity number which is almost three orders of magnitude greater than those for globular morphology, The current research have, for the first time, shown the validity and reliability of "parallel plate compression viscometry" method in characterizing microstructural evolution of Rheocast SSM billets.

Jan 1, 2005

When the Organic Act of 1910 established the Bureau of Mines within the Department of the Interior, the Bureau&apos;s programs involved only health and safety research and education, and fuels testing. As the Federal Government&apos;s primary agency for research in minerals, the Bureau has expanded its scientific and technological investigations to mining, processing minerals substances, eliminating occupational health and safety hazards in the mineral industries, economic development, and resource conservation. Today, Bureau activities cover a broad spectrum of programs for meeting the diverse (and sometimes conflicting) needs of mineral industries, government, and the public. In the 1960&apos;s, the Bureau initiated programs to resolve environmental problems associated with past mining and mineral processing. In the 1970&apos;s, the energy crisis raised the national consciousness concerning our limited supplies of domestic mineral and fuel resources. Dependence on foreign sources of raw materials critical to our national economy and competition from other countries for these world supplies stimulated the need to conserve and use with intelligence the Nation&apos;s minerals, metals, and fuels.

Jan 1, 1976

By Charles F. Jackson

Gold mining is a subject that not only appeals to the popular imagination but has vital importance to the world&apos;s economic structure. However, a discussion of the use of gold as a medium of exchange, and a basis for credit between nations and for monetary systems is not within the scope of this paper. The importance of gold in carrying on the commerce of the world, the present supply and rate of production, the probable trend of future production, the probable future requirements, and related subjects have recently received much attention from bankers and economists, and many articles on these subjects have been published. During slack periods of base-metal production due to falling prices, accompanied by scaling down of base-metal mining operations and often by the closing down of at least some mines, there usually result revival of interest in gold mining, search for previously undiscovered deposits, and reopening of some old gold mines.

Jan 1, 1932

By VAN. H. MANNING

Probably no year in the history of the United States showed greater progress in the mineral industries than 1916. Although this progress was undoubtedly stimulated by the war in Europe, which caused extremely high prices for some of the metals, yet the fact remains that mining is being regarded more as a business and less as a speculation, and the benefits of business methods are becoming evident. Practices that were almost universal a few years ago have been largely abolished, the mining public has been brought to recognize the folly of wasteful and dangerous methods, and there is a gratifying unanimity of opinion in regard to the conservation of life and health, as well as of our mineral resources. The people of the United States realize more fully than ever before the extent and value of the country's mineral resources and the possibilities that await intelligent and well-directed efforts at utilization. In the past, economic reasons caused deposits of valuable metals and industrial materials to lie idle; commercial reasons, many of them not truly economic, led to the waste of valuable constituents in many ores; the recovery of minerals from the ground was too often incomplete and accompanied by uncalculated loss; and the treatment of ores in mills and smelters saved altogether too Iowa proportion of the metals sought. Now better methods are being tried on every hand, and the unparalleled record of the year is largely due to the success of these efforts. According to the preliminary estimates of the United States Geological Survey the output of metals and minerals in this country in the calendar year 1916 had a total gross value of slightly more than $3,000,000,000. For many metals and minerals the figures broke all previous records, the new records of some products, as compared with 1915 figures, being as follows:

Jan 1, 1917

By IPMI Educational and Scientific Foundation

It is with great pleasure that we announce the availability of this fourth issue of the IPMI Journal, a publication of the International Precious Metals Educational and Scientific Foundation. This digital peer reviewed publication has been created as a vehicle for the sharing of technical information related to the science and technology of precious metals. Since 1976, the International Precious Metals Institute has championed the exchange of information of critical importance to the precious metals scientific and commercial communities through its various communications vehicles. This has included instructional videos, annual conference symposia, special topic committee meetings, regional seminars, and professional and student achievement awards. Due to the breadth of important topics related to all aspects of precious metals, it has been the vision of the IPMI to provide a publication available to the general public that would become a key source of pertinent topics containing high quality publications by experts in their fields of study. Historically, the IPMI has attracted world renowned experts in many fields (including Nobel Laureates Henry Taube, Ei-ishi Negishi, Robert Grubs, Professor Ben Feringa, and David MacMillan) in the dissemination of discoveries, inventions, and industry proven practices. Such information has a total value greater than the sum of its parts as seemingly unrelated innovations from distinct focus areas can be adapted to solve problems. Because of this important characteristic of information exchange, we have decided to create a digital journal, available to the general public, that will not only communicate state of the art discoveries and sound practices, but will also review historical communications from the IPMI’s archives that have value and use even in today’s environment. On behalf of the members and leaders of the IPMI, we hope you will find value in this new publication.

Dec 1, 2020

Alfred Nobel first invented a practical detonator in 1863 and then the blasting cap in 1865. At that time the detonator was used on the end of a length of safety fuse to initiate nitroglycerine-based explosives. Since then the detonator has gone through a number of changes. The instantaneous electric detonator was the first to allow remote firing. The electric delay detonator followed and allowed for timing between holes. In the mid 1970s the NONEL« Tube was invented. This tube combined with NONEL« detonators meant that many of the safety issues, such as stray current and radio frequency, associated with electric delay detonators were eliminated. This system gave the mining industry a reliable and fairly accurate system with which to detonate shots of any size. Since the early 1980s a large amount of research and development work has been done around the world to create a more accurate detonator for the mining and quarrying industry. After years of research, electronic detonators have emerged as the most accurate and precise initiation system available to the mining and quarry industry today. Electronics provide the user with millisecond timing accuracy. The improved level of timing control allows operations to improve fragmentation, throw and reduce vibration levels. There are now a number of different electronic detonator suppliers on the market today. In 2004 Dyno Nobel formed a joint venture called DetNet with AECI. DetNet has a suite of electronic detonators: DigiDet«, HotShot« and QuickShot«. This paper will focus on the HotShot« system, the first of the three new initiation systems to be released to the market in Australia by Dyno Nobel.

Jan 1, 2005

By R Winterberg

Concrete is a well established and reliable construction material for the permanent lining of tunnels, but shows some weak performance characteristics, which can be overcome by the addition of specialised fibre reinforcement. This paper addresses the particular performance design requirements of segmental linings, discussing the improvements of fi bres on concrete properties. Focus is made on the beneficial effects of fibre reinforcement on the cracking behaviour and the toughness performance, providing a safe and durable tunnel lining.Not only the mechanical performance of fibre reinforced concrete (FRC) for segmental linings, but also the durability of the linings has gained growing attention among the designers and consultants. Especially tunnel linings with exposure to media with corrosion potential, such as wastewater sewer tunnels or desalination plant outfall tunnels, have high requirements on their durability. The design of these structures must provide a comprehensive study of durability aspects. Fibre reinforcement can substantially improve the durability of concrete.Research has been carried out on the cracking behaviour of concrete. The beneficial effects of steel fibres on the cracking behaviour reduce the permeability by reducing the flow paths within the concrete. Crack bridging steel fibres create necking effects in bending cracks, leading to earlier closure of the cracks. Further, steel fibres create particular crack formations, which lead to a substantial reduction of the fl ow rates through separation cracks. The results also show that considerable cost savings can be achieved using FRC, as the thickness of the linings can be reduced.The durability design issues will be addressed and underlined by a case history on the Hobson Bay sewer tunnel in Auckland, New Zealand.

Mar 8, 2011

By Derrick Chambers, George Kevin Chapin, M. Shawn Boltz

Seismic monitoring is one of the few noninvasive technologies with the potential to provide sub-surface geomechanical information to operators of large open-pit mines. Although passive seismic data has been used to refine emerging failure geometries and provide advance indication of surface deformations in the literature, doing so reliably in an operational context is much more difficult. This is due in part to difficulties in estimating and interpreting source locations and parameters in complex, low-stress open-pit environments. Additionally, the high costs associated with implementing, operating, and maintaining deep borehole seismic networks, which are most commonly used to monitor large open pits, can be difficult to justify, especially if monitoring benefits are not readily apparent. In this study, we explore the use of a near-surface nodal seismic deployment, which is commonly used in oil and gas exploration, for monitoring open-pit mining-related seismicity on a short-term basis. A deployment of 18 geophones was conducted on the surface in and around the Bingham Canyon Mine, a large open-pit mine near Salt Lake City, Utah, USA, where we find the small seismic array can detect and locate a variety of mining-related seismic sources, even with an extremely simplified velocity model. We outline the process of creating an idealized velocity model, developing a local magnitude scale, and interpreting the observed seismicity. Of note, we analyze a sequence of mining-induced events associated with a known structure on the south pit wall. We conclude with discussion on how surface-based deployments may be used to augment, or in some cases supplant, borehole seismic networks at large open-pit mines depending on monitoring requirements and objectives.

Apr 26, 2022

By BARONJUPTNER VON JONSTORFF, Andrew A. Blair, GUNNAR DILLNER

IT is a well-known fact that the results of different analysts, when operating on the same identical sample of steel or iron, are far from concordant, and it not infrequently happens that great annoyance and trouble in the commercial community are occasioned by these discrepancies. Attempts have been made at various times to investigate the causes of such differences and to obtain more reliable methods of analysis. The most important of these was made by the British Association in 1889: The following gentlemen, with Sir W. Roberts-Austen as Chairman, and Professor T. Turner as Secretary, were constituted as a committee to investigate the question, viz.: Sir F. A. Abel, Mr. Edward Riley, Mr. G. J. Snelus, Mr. John Spiller, Professor J. W. Langley, and Professor Tilden. Average .samples of steel were prepared in America under the superintendence of Professor J. W. Langley. The steels, in the form of turnings, were divided and distributed to sub-committees in Great Britain, America, France, Germany, and Sweden. In Sweden Professor Åkerman acted as Secretary to the Swedish committee. The Government Department of Tests was appointed in Germany; Mr. Ferd. Gautier in France; the British Association Committee in England; Messrs. William

Mar 1, 1905

By Gabriel Böde Jimenez Leon, Michael Karmis, Christopher Newman, Zach Agioutantis

"When utilizing high recovery underground mining methods, such as longwall or high-extraction room-and-pillar mining, the movement and deformation of the overburden propagate toward the surface and may affect the integrity of overlying surface streams (Peng et al, 1996). Published studies cite three major mechanisms of subsidence as most likely to impact streams: displacement, slope and strain. While subsidence-induced vertical displacement cause little structural damage to the stream bed, it may create adverse drainage and stream flow issues as the subsidence trough allows for ponding (Dawkins, 2003). Subsidenceinduced changes to the slope, or tilt, of a stream may have adverse effects on water flow. As the stream enters the subsidence trough, the gradient increases providing potential erosion control problems. When exiting the subsidence trough, a reduction of the gradient may inhibit stream flow, causing localized ponding (Peng, 2008). While vertical displacement and tilt both may have detrimental effects to surface streams, the resulting strains have been documented as being the most damaging to surface streams and structures causing distortion, fractures, or failure (Singh, 1992). When stream beds are subjected to high tensile strain, tensile cracks may form at the surface level allowing for the direct loss of stream flow through fissures. When stream beds are located in areas of high compressive strain, rock layers forming the stream bed can fail as the stream bed ruptures, upward, blocking stream flow or having the stream diverted into the fracture zone at the base (Iannacchione, et. al., 2010).Recent investigations on the effects of underground mining on surface bodies of water suggest that to determine the degree of stream impact one must also consider the geologic structure and thicknesses, surface topography, watershed drainage areas, width of river bed and rate of mining. Due to the complex nature and number of parameters affecting surface streams, subsidence modeling tools and software packages should be implemented throughout all stages of subsidence planning, prediction and control. The Surface Deformation Prediction System (SDPS) utilizes the influence function for the calculation of final subsidence deformations with respect to the angle of influence, supercritical subsidence factor as a function of the percent hard rock, edge effect offset distance, and surface topography. Developed more than 25 years ago, SDPS has been continually updated with new analysis and prediction features, providing a reliable and versatile program for subsidence management methodologies. Most recently, the program has been updated to evaluate the effect of varying surface topography in the prediction of horizontal displacements, referred to as ground strain, allowing for the accurate three-dimensional representation of surface deformations in mountainous terrain (Agioutantis and Karmis, 2014). Ground strain has become one of the predominant deformation indices used in the evaluation of potential damage to surface structures (Karmis et al., 1995). Ongoing work with SDPS software seeks to investigate the calculation of ground strain in SDPS and its ability to accurately and realistically predict damage to surface streams due to underground mining operations."

Jan 1, 2015

By Graeme Lamson, Rene Dobbe, Merle Kalstrom, Janice Baron, Robert Thorpe, Chris Martin, Snezana Bajic, Amanda Palko

"This paper presents early results from a case study at the Mount Polley porphyry copper mine in British Columbia, Canada. Daily mineralogical data was acquired and reconciled with daily plant assay and recovery balances to interrogate the mineralogical controls on plant performance. After commissioning, the Minesite machine operated smoothly and reliably, creating daily data to generate mineralogical balances around the circuit for a period of several weeks. The key data, on final products were produced within 13 hours of the end of the respective operating period. The resulting information allowed for a greater understanding of the opportunities and limitations of the Mount Polley metallurgy. In this paper, how this information can be used to help long term strategic planning for the operation, as well as mine planning and production forecasting and the fine tuning of day to day mill operations is described. Early data available at the time of preparing this paper indicated that roughly 40% of the sulphide losses, or 32% of total copper losses existed as low grade inclusions in +75 micron tails. This represented the dominant form of long term copper losses, demonstrated repeatedly in the routine analytical data. However, on a day-to-day basis, the amount of copper present as chrysocolla is the major driver behind variations in total copper recovery. The degree to which this influences mill recovery is valuable to the geologist or mine planner. As they are armed with mineral speciation information for future ores, this will allow for improved mine planning, prediction of copper recoveries and production forecasting. The data was also started to find value in the mill by showing what caused sulphide losses. In the roughers, for example, the data showed poor recovery was the result of poor flotation performance and not any changes the speciation of copper sulphides or their liberation characteristics."

Jan 1, 2014