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In this paper a numerical formulation is presented for determination of the axial load along a cable bolt for a prescribed distribution of rock mass displacement. Results using the program CABLE indicate that during excavation, the load distribution that develops along an untensioned fully grouted cable bolt depends on three main factors: (i) the properties of the cable itself, (ii) the shear force that develops due to bond at the cable-grout interface (i.e. bond stiffness), and (iii) the distribution of rock mass displacement along the cable bolt length. In general, the effect of low modulus rock and mining induced stress decreases in reducing bond strength as determined from short embedment length tests, is reflected in the development of axial loads significantly less than the ultimate tensile capacity even for long cable bolts. However, the load distribution is also dependent on the deformation distribution in the reinforced rock mass. Higher cable bolt loads will be developed for a rock mass that behaves as a discontinuum with deformation concentrated on a few fractures, than for one which behaves as a continuum, either due to a total lack of fractures or a very high fracture density. This result suggests that the stiffness of a fully grouted cable bolt is not simply a characteristic of the bolt and grout used, but also of the deformation behavior of the ground. In other words, the same combination of bolt and grout will be stiffer if the rock behaves as a discontinuum than if it behaves as a continuum. This paper also explains the laboratory test programme used to determine the constitutive behavior of the Garford bulb and Nutcase cables bolts. Details of the test setup as well as the obtained results are summarized and discussed.

Jan 1, 1996

By Jose A. Gomez, Javad Sattarvand

Failures of tailings dams have been happening lately. Due to the lack of laws on particular design criteria and stability requirements related monitoring during construction and maintenance, they are thought to be more fragile than hydraulic dams. Monitoring the dam is therefore necessary to understand its current condition and guarantee its safety. The physical condition of the dam could be evaluated with the early identification of seepage. Additionally, due to their adaptability and capacity for high-resolution data collecting, UAVs are an excellent choice for efficiently covering the tailings dam site. UAVs may capture high-quality photos when equipped with a high-resolution RGB camera, thermal sensors, or multispectral sensors. When these sensors are paired with image processing and machine learning algorithms, the result is a reliable estimate of the dam condition.

Jun 25, 2023

Geophysical methods are useful non-invasive means of collecting subsurface information on the environmental impacts of resource developments. Techniques such as seismic refraction, ground probing radar and magnetics are well established tools for environmental studies of waste disposal sites. Repeat resistivity surveys, gravity surveys, and infrared or multispectral remote sensing hold great promise for monitoring environmental changes. Examples from New Zealand include geothermal field monitoring, which may involve the use of geophysics for .detecting changes of surface thermal activity, hydrothermal eruptions, induced earthquakes, contamination or depletion of shallow groundwater, and subsurface fluid recharge. Other examples include resistivity monitoring of contained effluent disposal ponds, tailings dams and landfills. Experience has shown that care is necessary to identify the natural variability of the parameter measured before drawing conclusions regarding an observed change.

Jan 1, 1994

By J. M. Ekenes

New approaches that increase hydrometallurgical recovery from refractory minerals in below-mill-cut-off-grade sulfide copper ore can add significant value, improve profitability and increase ore reserves. This paper describes the development and implementation of an engineered heap (EH) approach to leaching low-grade, chalcopyrite-bearing ore at Freeport-McMoRan?s mine in Morenci, Arizona. The technical evolution of the engineered heap concept is described together with the challenges and benefits following implementation.

Jan 1, 2012

By Li Jiuping, Zhong Gang, Chen Yong Zhang, I. Michael Gowring

The Liaoning Dahuofang Reservoir Water Transfer Project is an important development for the Department of Water Resources of Liaoning Province in northeastern China. The 85.3 km water conduit will transport water from the Hun River downstream of the Huanren Reservoir to the outlet on the Suzi River leading to the Dahuofang Reservoir. The additional water is required to sustain the growing cities of Fushun, Shen-yang, Liaoyang, Anshan, Panjin and Yingkou. The project is divided into seven contracts. Three TBM contracts comprise almost 75% of the work and the others are drill and shoot. The focus of this paper is about the creditable TBM performances achieved and some of the problems encountered by Chinese contractors; notably two having had no previous TBM experience.

Jan 1, 2007

By S. C. Tadolini

Roof support systems have evolved from standing posts and timbers to a generation termed ?big nails? where steel bars are inserted into boreholes and anchored with expansion shells and/or resin cartridges. These systems have been effective but are limited to mining height. Additionally, the properties of steel do not resists shear forces or have the flexibility being required in difficult ground conditions. The next generation of roof support systems is coupling the best parts of the ?big nail? and resin grouted cable bolt systems. This paper will present the advanced technical solutions of the next generation of cable systems that includes an indented high-capacity PC-strand used with a variety of fixtures. Case histories of support applications will be presented.

Jan 1, 2012

By Edwards A. B

A table concentrate obtained experimentally by the New Occidental Gold Mines N.L. has unusual interest on account of the presence in it of abundant coated or "black" gold. The concentrate was obtained from ore from the New Cobar mine, Cobar, New South Wales, by feeding the oversize product from a "Dorr Bowl classifier to a Card table.Its assay value was 129 oz. of gold and 52 oz. of silver per ton, yet practically no free gold could be seen on panning.When, however, the concentrate was digested in hydrochloric acid fine rusty gold could be obtained by panning.The following chemical analysis was carried out by the mining company on a similar sample of concentrate.

Jan 1, 1941

THE township of Costerfield is situated in the parish of Costerfield, county of Dalhousie, and lies 6 miles east of Heathcote and 30 miles south-east of Bendigo. It is separated from Heathcote by the Mt. Ida Range, which forms the western boundary of the Silurian formation. It is situated at the head-waters of Tin-pot Creek, a small southerly tributary of the Deegay Ponds Creek, which flows east to the Goulburn River.The field was discovered in 1860 by two prospectors, Coster and Field, who were guided there by a shepherd, M Nicol Coster and Field had already discovered an antimony lode about three miles nearer Heathcote, when M Nicol offered to guide them to the larger outcrop. The main Costerfield reef at that time projected above the surface, and was white through oxidation, though the bluey sulphide showed on fracture. No alluvial gold of any consequence was obtained at Costerfield, but a little was obtained, at Redcastle, 7 miles to the north, and in some of the gullies to the east.Following its discovery there came a period of prosperity to Costerfield, while the mining operations were confined to the oxidized zone. The early success of mining at Costerfield was due to the gold values, and it is probable that the oxidized zone was secondarily enriched. The earliest available record of values is a crushing of Coster and Co. on the Antimony reef (now known as the Costerfield reef), when 200 tons from a depth of 70 ft. averaged 4 oz. per ton in July, 1861. At this time a crushing mill had not yet been erected at Costerfield, and the ore was carted and treated at Redcastle. The massive antimony ore, consisting of mixed oxides and sulphides, was separated by hand-picking as "marketable ore," and the remainder crushed for gold. A higher average is recorded from South Costerfield in September, 1861, when a 15' cwt. parcel...

Jan 1, 1922

By J. L. Jambor, T. C. Birkett, W. D. Sinclair

Abstract -The rare-earth elements (REE) form a significant part of the group of so-called "high­ technology" metals whose glamour has attracted both the scientific community and the mining industry. Despite this attraction, world production of REE declined abruptly in 1985 and only recently has begun to approach production levels of 1984. The decline in 1985 was primarily due to decreased demand for light REE used as catalysts in the production of lead-bearing gasoline. Incorporated within the current trend toward increased production of REE is an increasing demand for higher value elements such as yttrium and other members of the heavy REE group, and for specific REE rather than mixed products . The former demand has made some Canadian deposits and prospects economically attractive despite a surplus of REE reserves on a world scale. The chief attractions of Canadian deposits such as Strange Lake, Labrador-Quebec, Thor Lake, Northwest Territories, and Kipawa, Quebec, are that they are relatively rich in yttrium and other heavy REE compared to light REE, and that they offer a potential security of supply to counterbalance the rapidly escalating dominance of China in the world market.

Jan 1, 1992

By T. Wang

A new generated NaNO3 ? NaNO2 ? KNO3 ternary thermal energy storage system which has low melting point as 124°C and high specific heat capacity was studied for the short and long?term thermal stability by using the Thermogravimetric Analyzer (TGA). Based on the actual working condition of molten salt in solar two, the simulated cyclic thermal stability measurement was also conducted. The ternary system demonstrates excellent short ? term thermal stability and thermal reliability after cyclic heating and cooling processes. However, in the long ? term as well as the simulated cyclic stability measurement, large amount of weight loss was observed. Moreover, the stepwise long ? term isothermal study reveals that below 440°C the weight change is minimal and this temperature is viewed as the upper limit temperature of thermal stability for this ternary system. To determine the lost phases at high temperature above the upper thermal stability limit, techniques such as XRD and SEM are used to compare the condition of the salt mixture before and after the long ? term thermal stability study. On the basis of the comparison, it can be concluded that the major weight loss was due to the decomposition of sodium nitrite.

Jan 1, 2012

By A. E. Taylor, A. S. Judge, P. T. Lafleche

"Resource development in northern Canada has special requirements which derive from the unique environmental and eco-logical nature of the northern environment. In this paper several case histories in which the Permafrost Research Section of the Geological Survey of Canada (GSC) has participated are used to illustrate how geophysical methods may be used to address some of these considerations. Although some of these examples were developed while examining problems directly related to oil and gas development and transport in frontier regions, such or similar methods also have application to mining problems.IntroductionA critical parameter is the distribution and thickness of permafrost, which in northern Canada varies from being a few metres and discontinuous at the southern limit to thicknesses in excess of 700 m in the Arctic Islands'!'. Figure I is a schematic diagram of typical ground thermal conditions in a permafrost zone. The upper zone is defined by an active layer which undergoes a seasonal freeze/thaw cycle. In the simplest case, the ground remains permanently frozen below the active layer to the depth of the O°C isotherm, which is defined as the base of the permafrost. Water chemistry, pore structure and pore or grain size may cause the base of the frozen ground to be above the permafrost by up to 100 m(2). Ice can be found within the permafrost in the pores of solid rock or sediments, as massive ice within unconsolidated sediments or as ice lenses within fissures in a solid rock mass. The mining technique used in these conditions, whether open pit or underground, can differ considerably from that used in southern Canada. In the high Arctic, for instance, the dry drift method is feasible underground in the permanently frozen host rock. The frozen nature of the wall rocks can obviate water-related problems."

Jan 1, 1987

By E. H. Herron, J. H. Perry

Mathematical simulation of reservoir behavior may be used to help understand reservoir processes and to predict reservoir behavior, thereby leading to the most economically desirable form of exploitation. In addition, simulation can be used as a tool for reservoir description to learn more about the physical nature of the reservoir and the mode of primary recovery. This use is essential in most reservoir studies and represents one of the more significant applications of simulation. Prediction of reservoir behavior provides information concerning displacement efficiency, optimum well locations, and the comparison of alternative producing processes. Since oil, water and gas all commonly occur in many reservoirs, a simulation that takes into account the simultaneous flow of three immiscible phases is a prerequisite for obtaining such information. Furthermore, a simulation that describes this flow in two dimensions provides the capability of evaluating combination gas- and water-drive reservoirs with either an areal or a cross-sectional description. Many reservoir problems require such a simulation. The objective of the research described here was to develop a mathematical model and associated computer program for accurate, efficient, and economical prediction of the reservoir flow of three phases in two-dimensional geometry. Several authors have discussed multidimensional reservoir simulation of two phases.l-3 Gottfried et al.' presented an analy- sis of three-phase simulation in one dimension. Fagin and Stewart" and Garrett6 have discussed the simulation of three-phase flow in two dimensions, but their solution techniques were different from the method discussed in this paper. In particular, previous models and computer programs have usually involved either fewer capabilities or inefficient and less rigorous descriptions resulting in limited applicability. In the following sections, we present a description of the model, an evaluation of the method, and the application to reservoir problems. Additional and supporting material is presented in the Appendix. The Three-Phase Model General Description The three-phase model consists of the mathematical description of the flow of oil, water and gas in a reservoir. Conceptually this description considers flow in all three space dimensions, but in the subject simulator it is assumed that no flow occurs in the third dimension. The model includes the effects on reservoir behavior of fluid and rock compressibility, viscosity, gravity, capillary pressure, relative permeability and gas solubility. Within the two-dimensional restriction, the reservoir considered may be completely heterogeneous and anisotropic. The differential equations governing multiphase, multidimensional flow in a reservoir are too complex to be solved analytically, so they are approximated by a system of finite difference equations and solved

Jan 1, 1970

By Makoto Kimura

Failure tests on laterally loaded single and pile group are analyzed with a 3-dimensional elasto-plastic finite element program. In the analysis, the mechanical behavior of the ground is supposed to be elasto-perfect plastic with Drucker-Prager's yielding criterion. The nonlinearity of the piles is simulated by assuming a hyperbolic relation between the bending moment and the curvature of the piles. The influence of the axial stress on the cast-in-place concrete piles is also considered in the numerical analysis. It is found that the mechanical behavior of the piles subjected to lateral loading, such as the load-displacement relation up to an ultimately large deformation, and the distribution of bending moment in the pile group can be well simulated.

Jan 1, 1996

Coal mining in New Zealand is principally a State-owned and controlled operation where the State produces 70 per cent of the coal in New Zealand and 65 per cent of coal mined in the Waikato. The State's flexibility in production quality and price makes them tough competition. Coal in the Waikato varies in quality considerably throughout the region making the high quality coal deposits as in the Huntly district a highly sought after commodity. The high quality of coal is often offset against transport costs as, for example, Maramarua coals can compete effectively in the Auckland market and dollar per calorific value basis.

Jan 1, 1984

By E. C. Lane

["_&apos;_-is is t`-e tenth in a series of retorts on proferties of cornmerci-al motor fuels, m,-_de in accord^nce ::ith a cooper: tine aSreement between the Cooperative Fuel scorch (C.F.R.) Committo e ^nd the. PPure__u of Mines of the United_ States De_nartr.ent of the Interior. Zee first report rave data. on motor gs.solir_es sold. during .e winter of 19,-"1-3b. e are ent report presents an^..lytico1 data f&apos;i&apos;r samples, rerrerentin_E, t:-.e products of apyroximately 90 conr.anies, hich, as in previous surveys, include both lame and stall surnliers. In ?_"dition, the Pacific coast is represented by data that were avera,;el ty the Pacific Coast Technical Group before bein submitted and are rublisi,ed exectly zis they were received. As in previous s?nrve,rs, the data r~Lre divided into the three groups of samples of regular-price, premiu::--trice, and third-grade gasolires, and each group has been averaged sel c~r~.tely. he number of nmtles, items, and brands comprising each groan), exclusive of those of the Pacific coast, are as folio:;s: Reg<.~-lar price, 934 ca.^rnles, 2c0 i to s, and ~0 brands; premium price, 460 saris les, lPitems, an&apos;. -C` brat&apos; i _~ t__ rd grade gaseline, 360 samples, 177 i te.^..s, and of these terms as _ised in the surveys are a:: follows:]

Jan 1, 1941

By D. Turk, P. Lefebvre, J. Sargent, K. Major

"Stillwater Mining Company recovers platinum and palladium from their Nye Montana operations. Mining first commenced at Nye in 1987 at a milling rate of 455 t/d (500 stpd). The plant was expanded in 1995 with the replacement of the ball mill and the addition of flotation capacity to increase mill throughput to 1820 t/d (2000 stpd). The applications for platinum and palladium have increased in recent years particularly in the automotive industry and the supply of the metals has remained fairly constant with prices for both platinum and palladium increasing and remaining very stable. In 1997 Stillwater initiated the expansion of their operations to increase production of platinum and palladium. Projects were initiated to expand production at the Nye operations, increase smelter and refining capacities at the Columbus facilities and to develop the extension of the orebody at the East Boulder site. This paper will discuss the changes at the Nye concentrator which were completed to increase production from 1820 t/d (2000 stpd) to 2730 t/d (3000 stpd) and eliminate some of the process bottlenecks.IntroductionStillwater Mining Company is mining the only significant primary source of PGMs outside of South Africa. The J-M Reef is an extensive mineralized zone containing PGMs that has been traced over a strike length of about 43 km (27 miles) in the southwest region of Montana. Stillwater controls the entire PGM mineralized zone.Johns-Manville geologists discovered palladium and platinum in the early 1970’s. In 1979, a Manville subsidiary entered into a partnership with Chevron, USA to develop the project. In 1 987, operations at the Stillwater property near Nye, Montana commenced."

Jan 1, 2000

By Jr. Jones

This paper is derived from a document that compiles autogenous and semi-autogenous mill installations worldwide, through the end of 2010. Updates have been solicited from all major mill manufacturers and most have responded. A review of AG/SAG mills sold to date and in the last five years indicates that the AG/SAG mill market is very healthy and the trend is larger diameter mills with high diameter-to-length ratios. Ring motors (gearless) are the preferred drives for large mills even though the power transmitted through a gear drive is expected to near 11,000 kW per pinion in the near future.

Jan 1, 2012

By Jon J. Indall

I. INTRODUCTION The challenge of moving the use of nuclear energy from military to civilian use was first issued by President Dwight Eisenhower in his December 8, 1953 “Atoms for Peace” speech delivered at the United Nations. Eisenhower stated: “The United States knows that if the fearful trend of atomic military build up can be reversed, this greatest of destructive forces can be developed into a great boon, for the benefit of all mankind. * * * * The more important responsibility of this Atomic Energy Agency would be to devise methods whereby this fissionable material would be allocated to serve the peaceful pursuits of mankind. Experts would be mobilized to apply atomic energy to the needs of agriculture, medicine, and other peaceful activities. A special purpose would be to provide abundant electrical energy in the power-starved areas of the world. In the 1950’s and 1960’s, the Atomic Energy Commission promoted the use of nuclear power as the answer to our nation’s energy problems. Nuclear power would provide energy too cheap to meter. The utility industry responded and numerous plants were planned with over one hundred constructed from the 1970’s to the 1990’s. Capital costs for nuclear power plants escalated due to permitting changes and public opposition, and the Three Mile Island incident caused new nuclear plant construction to cease. Today, we once again are experiencing a nuclear renaissance. Concerns over global warming and rapid projected increases in the demand for electricity have caused many nations to begin construction of new nuclear fleets. The price of uranium to fuel these reactors, which had dropped to an historical low of $7.10 in 2001, has surged to $56.00 as of October 2006. This paper will review some of the social, environmental, and government issues that are all playing a role in the resurgence of the nuclear fuel industry.

Jan 1, 2007

By Stanley Lefond

The health of the industrial minerals industry appears to be improving year by year. In fact, preliminary information suggests that only three commodities (asbestos, bromine, and sulfur-other) failed to show a production gain in 1984 over 1983. In 1983, 10 commodities failed to post gains and six remained constant. The total value of industrial mineral production in 1984 was $16.7 billion, up $1.4 billion from 1983. Cement, clays, gypsum, and crushed stone production increased. Since these are used in housing and construction, this suggests these industries are moving out of their recent doldrums. Barite and clay production also improved in 1984. Local US barite production, however, still has a long way to go to attain the 1981 high of 2.6 Mt (2.9 million st). Barite imports remain high. But they are not as high as the 1982 importation of 2 Mt (2.3 million st). Bentonite production in 1984 increased 20% in volume and 25% in value over the previous year. This suggests improvement in the drilling industry and an increase in demand for iron ore pelletizing grades. All in all, the industrial mineral industry is alive and well. And it shows signs of great improvement in the next few years. Many thanks to those industrial mineral technical committee members for their assistance in assembling this industrial minerals review: M. F. Dibble, H. W. Allen, G. H. Gallup, S. G. Ampian, D. W. L. Spry, H. G. Fleshman, and L. J. Czel.

Jan 5, 1985

By F. Dieu, C. Laughton

CERN, the European Laboratory for Particle Physics, is, at present, constructing an underground tunnel and cavern network to house a Large Electron Positron (LEP) colliding beam machine. This paper describes the techniques adopted to permit the excavation and temporary support of the access shafts through a series of glacial moraines, at depths of up to 80 m, to reach the bed-rock. Owing to the presence of superficial and deep water-tables, the variable nature of the moraine deposits and, above all, the tight work schedule, a combination of diaphragm walling and ground freezing was employed.

Jan 1, 1987