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By Bengt H. Fellenius

The design of pile foundations is much more commonly verified by means of a full-scale test, than is the design of other foundation units. The reason is not that our knowledge of pile behavior is more uncertain than our knowledge of other foundation types making the verification necessary, but more that the loads in a structure are more concentrated to single foundations in a structure founded on piles as opposed to structures on footings or mats. Therefore, should a pile cap fail or move, the adverse consequence of this is often drastic, as the piled structure has little freedom to transfer its need for support to other foundation units. Consequently, it becomes important to assure the design of piled foundations. In many, maybe in most instances, the static pile loading test is routine and geared toward determining an at least capacity, only. However, in these times there is an ever increasing liability of the professional, demands for increased economy of the foundation, and frequent lack of the involvement in the test of the experienced old-timer exercising good judgment. Furthermore, modern pile design is leaving the single, simple concept of capacity and requires more information from the test to assist in determining aspects of long-term behavior and settlement. Therefore, even the straight forward, routine static loading test requires improved planning, execution, and analysis.

Jan 1, 1990

By Alfred W. G. Wilson

In this paper is presented a review of the changes that have taken place in certain Canadian non-metallic mineral industries since 1909. The fifteen-year period 1909 to 1923, inclusive, has been selected for two reasons. In the first place, statistical treatment of the subject under review has been nearly uniform throughout the period. In the second place, this decade and a half is itself further subdivisible into three well marked quinquennial periods, the middle one covering the period of the great war when industrial conditions were greatly disturbed. It then becomes possible to institute certain comparisons between equal periods before and after the war disturbances. The items selected for inclusion in this review are certain of the more important members of that class of minerals usually grouped together under the heading of non-metallics. They are all minerals of which Canada is known to possess important resources, and which are indispensable to many of our greatest manufacturing industries.

Jan 1, 1925

By Arthur La Motte

I NDUSTRIAL explosives, as distinguished from military explosives, include high explosives and blasting powder. The high explosives which are best known are straight dynamite, gelatin dynamite, ammonia dynamite and permissibles. There are two kinds of blasting powder, saltpetre blasting powder and nitrate of soda blasting powder. Blasting powders are mechanical mixtures of nitrate of potash or nitrate of soda with sulfur and charcoal, highly compressed, granulated and glazed. They ignite from a spark and burn with relative slowness, the rate of burning and hence the rate of conversion into gases depending upon the size of the granulation and upon the degree of. confinement under which the powder is placed. High explosives, on the other hand, are chemical compounds which detonate; that is, when the explosive is subjected to a violent shock, provided in practice by a blasting cap or an electric blasting cap, the molecule of the essential ingredient, usually nitroglycerin, is disrupted and the energy and heat released cause any other explosive ingredients which may be present, such as ammoniuin nitrate or T.N.T., to decompose with a resultant evolution of gases at an extremely rapid rate varying from 6000 to 20,000 ft. per second.

Jan 1, 1924

By Benjamin Smith Lyman

PAGE I. ANCIENT HISTORY,........... 57 Accepted Fables ; Babylonian Mapping ; First Surveying. II. COMPASS,.............59 Chinese Invention; Marco Polo; First European Compasses ; Early Knowledge of Variation ; Plotting with the Compass ; Hanging-Com pass ; Supposed Gravitational Error ; Merit of the Compass. 111. Telescope,............63 Origin (Roger Bacon, Porta, Digges, Lippershey, Galileo) ; Improvements (Micrometer and Cross-Hairs, Rittenhouse's First Telescope, Platinum Cross-Wires, Telescopic Sights, Reflecting Telescope, Achromatic Lens, Kellner Lens in Erecting Telescope, Inverting Telescope). IV. Theodolite,.............81 Origin ; Derivation of the Name. V. TranBit,.............86 First Surveying Transit; Edmund Draper. VI. Instrument-Parts,..........89 Ramsdenl a Dividing Engine ; Fineness of Graduation ; Conical Gradua tions ; Full Vertical Circle ; Leveling-Screws ; Shifting Tripod-Heads ; Hoffman-Harden Tripod-Head ; Heller & Brightly's Improvements. VII. OTHER INSTRUMENTS AND APPLIANCES,......100 Sunflower; Plummet-Lamp; Chains and Tapes. VIII. SCOTT'S TACHYMETER,.........104 IX. Nomenclature and Classification,.......105 Names; Grouping. Surveyors are much indebted to Mr. Scott for so vigorously attacking the subject of the origin and history of mine-surveging instruments, the compass, the telescope, the transit and other apparatus. He is not afraid of the dark, nor yet foolishly bashful in broad daylight. He does not recoil from the obscurities of the earliest times and the most difficult historical points; and, with commendable public spirit, he makes his own invention known to his fellow-workers, and challenges their criticism. He has, moreover, elicited the praiseworthy emula-

Jan 1, 1902

By Y. Pan, V. V. S. Vytla, P. Tukkaraja, R. BHARGAVA, S. Jayaraman Sridharan

Panel caving is an underground bulk mining method that utilizes gravitational force for mining massive, steeply dipping, and deep-seated ore deposits at a lower operating cost. To control dust and gas emissions entering the production level during the extraction of ore from the draw points in a panel cave, relatively negative pressure is created in the cave by installing an exhaust fan in the exhaust drift located on top of the cave. Since caving is a dynamic process, the design of an effective ventilation system is a challenging task, and therefore, estimation of airflow resistance offered by the broken rock inside the cave is critical. The complex and dynamic nature of caving also makes it difficult to predict the airflow resistance by using traditional approaches. This study investigates the effect of changes in the bulk porosity of the broken rock on the cave airflow resistance using computational fluid dynamics (CFD) approach. The results show an inverse relationship between the cave airflow resistance and the bulk cave porosity. The pressure-quantity characteristic curves presented in this paper provide valuable information for sizing and operating an exhaust fan used for a mature panel cave ventilation.

May 17, 2022

By J. E. Nesset, J. A. Finch, Rosenblum. F., S. Somot

"In a previous presentation at the CMP, evidence was shown for the formation of hydrogen sulphide (H2S) in self-heating experiments on pyrrhotite-rich samples (Somot and Finch, 2006). Oxidation of H2S is strongly exothermic leading to the proposition that H2S is playing a key role in the self-heating process. Subsequently, tests in two weathering apparatus (I and II) were run under varying oxygen levels to further examine conditions leading to self-heating. To characterise their resulting self-heating capacity the samples from the weathering tests were subjected to a modified Stage B test using the self-heating apparatus developed by Rosenblum and co-workers (Rosenblum and Spira, 1995; Rosenblum et al., 2001). Results showed highest self-heating after weathering occurs under low oxygen conditions, supporting the H2S hypothesis. It was observed that highest heating rates are not directly related to highest weight gains of samples.INTRODUCTION“Sulphides” refer to several types of minerals containing sulphur in its lowest oxidation state of - 2. Self-heating is the spontaneous heating of a material without external heat input. It is well established that some sulphides will self-heat on exposure to moisture and oxygen (Farnsworth, 1977; Good, 1977; Rosenblum et al., 2001; Wu and Li, 2005). This process is highly exothermic and if the heat generated is not dissipated, combustion may occur when the temperature reaches the ignition point of the sulphide (typically 350-400 °C). The hazards of sulphide self-heating range from handling hot material, to sulphur dioxide release, to fires. The literature documents self-heating incidents underground, on ships and trucks transporting sulphide concentrates, and in mine waste (tailing) disposal areas (Stachulak, 1990; Lukaszewski, 1969; Headley et al., 1977). Lukaszewski (1969), Farnsworth (1977), and Good (1977) note that sulphide minerals can act as fuel to promote underground mine fires. Based on such findings, sulphide minerals could become classified as hazardous materials, making transport of concentrates and storage of mine waste subject to stricter and more costly regulation. The problem is one the industry is keen to avoid."

Jan 1, 2009

By K. G. Chipman

The Geological Survey is the oldest map making department in the Canadian Government service, and when organized in 1842, one of the first principles to be recognized was the absolute necessity of having good maps. The primary purpose of the Survey has always been geology; but because a graphic representation by means of maps makes the written report .more readily intelligible; because the correlation of known geological facts is often difficult or nearly impossible unless they can be represented on a map; and, because the public demand information shown in this way, the Geological Survey must continue to supply maps; and the supplying of these maps must be considered as an essential part of the work of the Survey. It is a commonly recognized principle of pedagogics that an appeal to the eye is quicker than one to the ear; that children (and others) learn more quickly when a thing is presented to them through the eye rather than through the ear. The application of this principle to the work of the Geological Survey is that, to a large number of people, the message of a map is more quickly grasped, is more readily intelligible, and is in many ways of more interest and value than is the same information in a report. I do not mean that the maps are of more importance than the reports.

Jan 1, 1924

A research and testing facility has been developed at Simtars to allow the spontaneous combustion testing of coal on a large scale. In this adiabatic reactor, the coal particle sizing is closer to that which could be found in the goaf and therefore the reaction is more likely to simulate the underground situation. This allows aspects of the spontaneous combustion process and methods for detecting a heating to be investigated which cannot be done in an operational mine. Up to 18 tonnes of run of mine or crushed coal is loaded into the reactor and allowed to self-heat while the temperature and gas profiles within the coal pile are monitored. The gases evolved from the coal are analysed using a fixed gas monitor system and gas chromatography to determine which of the common mine fire indicators and ratios can be used to predict the onset and progress of coal heatings. Benchmarking of the inherent propensity of a coal to spontaneously combust at both the large- and laboratory-scale is also possible by comparing the sample against previously tested samples. It has been found that the coal particle size affects both the time it takes for the coal to react and the location of the developing heating. The heatings generate approximately one metre from the inlet but in the crushed coal case do not progress to an advanced heating stage until the æhot spotÆ migrates towards the coal surface where there is an increased oxygen supply. Physical properties such as the compressive strength of the coal also affect the heating size and the time it takes for a heating to develop. Higher strength coals appear to oxidise more slowly and therefore take longer to self-heat as oxidation of the coal is the heat-generating step in the spontaneous combustion process. The best indicators of the state of the heating were found to be CO make and GrahamÆs ratio which are independent of air flow. Investigation of a potential spontaneous combustion should begin as soon as the CO make or GrahamÆs ratio exceed the background levels. The results from the tests undertaken on a number of Queensland and NSW coals are reported here together with the implications for the mining industry.

Jan 1, 2005

By S. S. M. Chan

The Bureau of Mines has investigated the structural aspects of shafts and support systems using the finite-element technique. In situ field measurements in deep, vein-type metal mines show that rock stresses are often higher in the horizontal direction than the vertical, and unequal in the horizontal plane. These data and laboratory and field-determined physical properties were used as input to analytical studies. Various design and construction parameters were investigated to deter-mine the effect on shaft stability. Rectangular shafts were studied in detail to determine the effects of applied stress ratio, shaft orientation and dimension, influence of interbedded quartzite and argillite, and rock fracturing. Various support systems were analyzed, including concrete lining, timber, and steel sets. Circular configurations were investigated to evaluate yield zones and liner thickness. Elliptical shafts and time effects were briefly evaluated to illustrate shape and time effects and demonstrate the methodology. It is shown that the magnitude, direction, and ratio of applied stress and rock mass anisotropy are keys to determining shaft stability. A realistic conceptual framework was developed with which to examine the rock and support interaction in deep mine shafts. Structural analysis techniques overcome some of the historical difficulties with shaft de-sign by defining the field data requirements and structural sensitivity of various design and construction parameters.

Jan 1, 1985

By J. B. McKay

It is the purpose of this paper to present an initial report on the construction and operation of the Fluo-Solid roaster at the property of Campbell Red Lake Mines, Ltd., Balmertown, Ontario. The roaster prepares for subsequent cyanidation the bulk flotation concentrate obtained from four hundred tons per day of gold ore. The mill flow-sheet 'includes jigging and amalgamation; flotation; cyanidation of flotation tailing; and roasting followed by cyanidaition of flotation concentrate plus amalgamation tailing. Overall mill recovery for the year 1950 was 90.2 per cent. Recovery possible by straight cyanidation of this ore would not exceed 80 per cent. The ore contains considerable arsenopyrite and pyrrhotite as well as pyrite, with lesser quantities of nickel, zinc, and copper minerals. The mineralization is for the most part extremely fine. The roaster first went into operation on August 7th, 1949, and at the end of 1950 it had roasted 10,916 tons of concentrate. The average recovery of gold from calcine during that period was 94.86 per cent in the primary stage of calcine cyanidation. The average assay of calcine residue from primary cyanidation for the entire period was 0.37 oz. per ton. Both laboratory tests and plant metallurgical balance calculations indicate a further recovery of approximately 10 per cent of this 0.37 oz. when the calcine residue is again cyanided, in the flotation tailing cyanidation circuit.

Jan 1, 1951

By David J. Kusler

This report describes a rapid, reliable, and relatively simple method developed by the Bureau of Mines Pyrometallurgy Laboratory at Bruceton, Pa., for determining lime (calcium oxide) and magnesia (magnesium oxide) in various materials containing these constituents in greater than trace amounts. Optionally, titania (titanium dioxide) may be determined for the same sample. The accuracy of the method, suitable for most purposes, is shown by comparing the Bureau results with those obtained by accepted procedures. The method has been applied satisfactorily to the routine analysis of blast-furnace slags, for which purpose it was primarily developed, and to other calcareous compositions. In the Pyrometallurgy Laboratory it has replaced the standard methods previously used to determine lime and magnesia, and has been in general use by that laboratory for the past several years. The analysis time, generally under 3 hours, is considerably less than required by standard methods.

Jan 1, 1960

"In addition to outstanding technical sessions and networking opportunities, the SME Annual Conference and Expo offers attendees a chance to see the latest and greatest technology that the industry has to offer. The 2017 SME Annual Conference and Expo was no exception as 575 companies filled 756 booths from Feb. 19-22 in Denver, CO. The following is a look at some of the vendors that were on hand.AIL MiningThe Edge, featured by AIL Mining at the 2017 SME exhibit, is a four-flange structural liner designed to be an alternative to structural plate’s traditional lapped seams and to help mine operators build more efficiently and safely. It is ideal for creating underground structures, such as mine shafts, ventilation raises and escape ways. The Edge is available on SuperCor structural steel plate — 10 times stiffer and five times stronger than traditional steel liner plate. It facilitates curved structures, both horizontal and vertical, and eliminates the need for ring beams. It is ideal for remote sites. For added safety, structures can be assembled from the inside, and the leak-resistant structures can be dismantled and removed easily. Brackets can be attached to mine shafts or vent raises to support Alimak rails or climbers. Similarly, brackets or hangers can be attached to drifts or tunnels to support mine air, water or electrical utility services.ArcadisMining companies spent nearly $12 billion on water infrastructure worldwide in 2014, reflecting the industry’s heightened concern about environmental issues and social, regulatory and political risks.So, with an increasing focus on water reuse and recycling, mining companies must have effective water management plans that include sustainable solutions. Also, many water quality issues fall under both state and federal regulatory jurisdictions. To solve these problems, Arcadis provides comprehensive ground- and surfacewater technical support in a complex hydrogeologic setting. It can characterize the nature and extent of mine-related constituents in ground water and surface water, as well as the complex interactions between the two waters, and prepare the operational permits needed by mine and tailings facilities. As an example, Arcadis constructed a hydrogeologic and geochemical conceptual site model that improved site understanding for a molybdenum mine in the western United States that spanned several watersheds. It also provided technical support for permitting and compliance issues, allowing the mine to return to active production."

Jan 5, 2017

By Patrick B. Kenny

Generally speaking, it is safe to address this conference as a conclave of Engineers, Owners' Agents, Governmental Representatives, and Contractors. As a group, we have assembled here to learn of our compatriots engaged in similiar underground operations throughout the United States and the World. We are here to learn of improved methods, higher technology, and better management. Through the acquisition of this knowledge, we each hope we can improve our own particular services, products and projects. This session is dedicated to a discussion of "Costs". The most apparent reason for a discussion of costs at this level is to expose subjects affecting costs and propose methods to reduce them. From that premise a contractor can identify three areas of discussion: design considerations, contract considerations, and governmental considerations. A fourth area of consideration is an introspective view of the contractor's role in the design construct process. Unnecessary costs and risks attributable to these areas are contributing excessively to ever increasing project and system costs. DESIGN CONSIDERATIONS On April 20, 1977 the Metropolitan Sanitary District of Greater Chicago accepted proposals for the Tunnel and Reservoir Plan on Contract A and Contract B. This letting called for construction of over 33 km (21 miles) of the Mainstream Tunnel bored at 9.75 m (32 ft) to 10.67 m (35 ft.) in diameter. Also included were all the appurtenant collecting and regulating structures. The proposal allowed the

Jan 1, 1979

By K. A. Clark

"The repacked mineral aggregates of good grade oil sands have permeabilities ranging between 15 darcys to 350 millidarcys. The variation is due to the silt contents of the aggregates. Few good grade oil sands contain as much as 30 per cent •silt, most of them contain less than 20 per cent, and a large proportion have less than 10 per cent.The permeabilities of repacked good grade oil sands (oil included) depend on the degree of liquid saturation. When saturation with oil plus water reaches between 80-90 per cent, permeability is reduced to zero. As total saturation decreases below 80 per cent, permeability increases ranidly. Permeabilities of between one and two darcys were observed for total saturations between 60-70 per cent.The mean value for 18 measurements of the permeabilities of ""undisturbed"" core samples of good grade oil sands was 50 millidarcys. This value is •probably too high. The mean value for 20 measurements on core samples of interbedded oil sand and shale was 100 millidarcys. The mean value for 11 measurements on shale was 10 millidarcys."

Jan 1, 1960

By N. J. Rarmrez, C. Perez, J. D. Calderon, L. Lopez

"Among the thermal characterization of any material, one of the variables to know is the coefficient of thermal conductivity because this value can tell how much heat passes through the material and if the material could be used as an isolator. In order to determine this parameter is required some kind of special equipment and controlled conditions which implies high costs in the development of tests. The present paper proposes a design of a low cost measurement system in order to determine this coefficient with the lower possible error. This equipment was thought for companies or labs where they do not have the economic resources or the infrastructure (environmental controlled labs, heat flux transducers, human resources with specialized knowledge) to do this kind of tests.The system is based on ASTM C 518 - 04 [l] and integrated by two plates (one that contains a thermal resistance and which temperature is controlled by a closed loop controller and the other one with a route of water flow). The thermal resistance is actuated by a relay and a supervisor system checks the total time the relay is on in order to determine the effective power applied to the system. The contact faces of the plates contain a group of temperature sensors connected to a data acquisition system that process and record the temperature in each measurement point.With the power applied to the system, the measurement of temperatures and a process of calibration is possible to determine the coefficient of thermal conductivity. IntroductionWithin the thermal characterization of a material of known variables is the coefficient of heat transfer, since this value can know the amount of heat the material is capable of transferring or isolating. To determine this ratio requires specialized equipment and controlled conditions, which implies high costs in the development of a test. This article proposes a design of a low cost machine to allow closer this coefficient with the least possible error. This equipment was done thinking about companies that do not have the infrastructure (laboratories, controlled environment, heat flux sensors, human resources expertise) and financial resources to conduct these tests."

Jan 1, 2011

By Francis C. Furman

Microscopic evidence indicates that the high sinterability of certain commercial dolomites is tied to specific dolomite textural characteristics. This study encompasses detailed characterization of the unprocessed dolomite and sintering doloma results. The chemical and mineralogical compositions, insoluble residue, chemistry homogeneity, crystal size, primary carbonate texture, secondary dolomite texture, deformation structure, porosity type, porosity, and density of the raw dolomite were observed. These characteristics are compared with sintering trials of <74um powder-compacts samples in which holding times were varied. The evolution of the dolomite characteristics are reviewed and related to the final sintered doloma characteristics. The critical characteristics of a single-stage sintering brick dolomite are the following: 1) primary oolitic texture, 2) dolomite purity, 3) dolomite stoichiometry 4) minimal impurities, less than 1 weight {%} Fe2O3 Al2O3 and SiO2, 5) chemical homogeneity, 6) high density, 7) very low porosity, S) very coarse homogeneous crystallinity, 9) nonplanar dolomite texture, 10) abundant strain related slip microdeformation structures, 11) minimal subsequent alteration. Even with grinding to <74um the nonplanar dolomite texture and slip deformation still have a major effect on doloma sintered density. The three newly identified characteristics of single-stage sintered refractory brick dolomite are their primary oolitic texture, secondary nonplanar texture and abundance of stress related microdeformation structures. The primary oolitic texture reflects a homogeneous pure carbonate with respect to chemistry and crystal size secondary nonplanar texture produces crystals with large surface area to volume ratio. Stress related slip deformation moves CO, groups in to the same site of another CO, group but different orientation which is very unstable. All of these characteristics may facilitate the formation of higher density dolorna sinters.

Jan 1, 1995

By S. Amid, D. Fisk

"Wireless technologies are permeating the mining and metals industry and enabling a myriad of benefits. With standards such as IEEE 802.11 for wireless devices and ISA100.11a for wireless field instruments protecting their investments, customers look to benefit from the cost and flexibility offered by wireless devices. Using wireless field instruments, plants are eliminating the costs associated with wired system by 50 to 70% and using these savings to install more field instruments, which, when used smartly, enables them to optimize their processes efficiency and equipment reliability. Wireless also empowers a mobile workforce by allowing them to have access to key process and maintenance data directly from the field. This paper describes how wireless can help operations and maintenance personnel to be more effective. Three case studies, illustrating how the mining and metals industry is taking advantage of the technology today, are presented:1.,Optimisation of the water recovery process using wireless2.,Field operations improvement with wireless handhelds3.,Improving fleet maintenance through wireless mobile equipment management"

Jan 1, 2011

By Max W. Ball

Our ever-increasing use of minerals has been the outstanding fact in our American economic development. The rise in our standard of living in the past century is without equal in human history. Nowhere in time or place has the man who works lived so well, or the man who cannot work been so well cared for. We live in a new world, even the poorest of us, that our forebears of 1849 could not have dreamed. That new world has come mainly from our use of minerals. Our per capita use of nonmineral products has grown too, but by only a modest amount. Food consumption per person has grown about 15 per cent in the past fifty years; lumber use per person ,has fallen 56 per cent and that of wood for fuel 65 per cent. Of all the products of field and forest, our use, per capita, may have increased by one fifth during the present century. In contrast, our per capita use of minerals has multiplied several times. Each of us uses 2% times as much steel and 16% times as much petroleum as our fathers used in 1900. In less than half a century our per capita consumption of all minerals has probably risen by 200 to 250 &apos;per cent. Man once built with wood; today he builds mainly with brick and stone and steel. Once he traveled by the power of hay and oats; today he travels by the power of coal and oil. Rubber made from minerals is already better for some uses than rubber tapped from trees; before long it will be better for most and perhaps all uses. Even our ladies&apos; graceful legs are clad in mineral fiber, where once animal or vegetable fiber would have covered them. Our high standard of living is a product of the machine.. The machine is made of minerals. The machine is driven by minerals. The machine age is a mineral age.

Jan 1, 1949

By C. Díaz

Roast-reduction smelting (RRS) of nickel concentrate, combined with flash smelting of copper concentrate, was one of the process options that Inco considered as a means of meeting its 1994 sulfur dioxide abatement target at its Copper Cliff operations. RRS involves deep roasting the nickel concentrate in fluid bed roasters. The roaster off-gas is heated in a sulfuric acid plant, and the low sulfur calcine is reduction smelted with coke in an electric furnace to yield a sulfur-deficient matte. The latter material is converted to Bessemer matte in Peirce-Smith converters, with minimal evolution of sulfur dioxide, and the converter slag is reverted to the electric furnace. Excellent nickel and cobalt recoveries are obtained. This paper discusses the development of RRS, including extensive commercial scale testing at Inco&apos;s Thompson Smelter, and its key operating parameters.

Jan 1, 1993

By C. T. Baroch

As part of a general program for investigating all phases of titanium production, argon was substituted for helium in the reduction step at the Bureau of Mines pilot plant, which employed a modification of the Kroll, or magnesium-reduction, process. Argon was substituted for helium in 108 of the 140 batches of sponge made during 1 month&apos;s reduction operations for July 1954. Argon was substituted for helium satisfactorily, with only slight modifications in technique. Metal quality, feed rate of TiC14, magnesium efficiency, and average production per batch were closely comparable with either gas. Argon runs were slightly more troublesome because of the formation of condensable chloride complexes, which tended to plug feed and vent lines and to entrap deposits of lower titanium chlorides on the reactor-pot lids. These lower chlorides were objection-able because they were pyrophoric and created obnoxious fumes when pots were opened. When feed and vent lines became plugged care was required in poking or unplugging these lines to prevent air from entering the reactor. These problems were relatively minor, and continued development of reactors and techniques for the use of argon should further minimize objectionable side reactions obtained when argon is used.

Jan 1, 1956