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SME's Annual Membership Report - 1961 Membership Directory

Jan 7, 1961

Recent data contributions to New Zealand Mesozoic terrane geology confirm the consensus interpretation thatNew Zealand grew by the progressive addition of material by plutonic and accretionary processes along the Gondwana margin. The data also: 1. emphasise the discontinuous but inter-related nature of these processes of continental growth, 2. better establish a direct Gondwana correlation of the Western Province and probable Gondwana provenance of at least some of the Eastern Province, 3. suggest specific times and places when passive or strike-slip rather than subduction regimes are recorded along the south Gondwana margin, and 4. potentially lead to interpretations emphasising parautochthonous rather than far travelled relationships between many New Zealand terranes.  

Jan 1, 1995

By Stephen P. Signer

To improve the understanding of the support interaction mechanics between grouted bolts and coal mine roofs and to help lay the foundations for improved design and evaluation techniques, the 0.8. Bureau of Mines has conducted laboratory, field, and analytical studies of the load transfer mechanics of grouted roof bolts. Mechanisms by which load is transferred from a bolt through the grout to the rock mass are analyzed. Strain gauges were installed on over 70 bolts and tested to observe the rate of load transfer when a force was applied at the bolt head. Laboratory and field tests were conducted to determine bolt-grout- rock interaction behavior in both the elastic and postyield phases. Long-term laboratory tests were run to determine the time-dependent properties of both polyester resin- and-gypsum-grouted bolts. Numerical studies using finite- element techniques were compared to the experimental results. Elastic tests showed that 90 pct of the applied load was transferred within 24 in of bolt length. Long-term tests indicated that creep is more significant in gypsum-grouted bolts than in resin- grouted bolts. Plastic studies showed that yielding of steel will translate down the length of the bolt from 6 to 20 in.

Jan 1, 1988

By Z. Xiao, A. R. Laplante

"The recovery of gold by gravity from grinding circuits differs from virtually all other gravity recovery approaches in that stage (or unit) recoveries are low, typically 1 to 5%, but overall recoveries are generally in the 25 to 60% range, because individual gold particles are presented many times to the primary recovery unit. Full-scale recovery is difficult to predict from benchscale tests. Further, maximizing metallurgical recovery is generally not the primary objective, because of the more efficient downstream recovery circuit (flotation or cyanidation). In this paper, a new concept, the gravity recovery effort, is presented to assist in the design and optimization of gold gravity circuits. It is defined as the product of the circulating load treated by the primary gravity unit, the recovery of this unit, and the gold room recovery. Predicted gold recovery is linked to the recovery effort, the size distribution of gravity recoverable gold (GRG), the dimensionless retention time in the mill and the partition curve of GRG. A case study of economic optimization of the gravity recovery effort is presented. INTRODUCTIONPredicting gold gravity recovery from grinding circuits has always been a hit-and-miss exercise. The problem can be traced to the highly variable gravity recoverable gold (GRG) content of ores, high GRG circulating load, fraction of the circulating load treated, and performance of primary gravity recovery and gold room. Typical values, highs and lows are shown in Table 1."

Jan 1, 2001

By Vedala Sastry

Longwall mining for coal extraction in deeper deposits is gaining momentum in India, due to the increasing stripping ratios and depletion of shallow deposits amenable for surface mining. In longwall mining, presence of multiple seams with varying interburden thickness is a major problem especially while planning for over-mining. An investigation program was taken up to analyze the effect of the presence of goaf and virgin coal blocks in already developed and extracted lower seam by bord and pillar mining, on the stress distribution in the longwall panel in upper seam. Studies revealed marginal increase in horizontal and shear stress as longwall face passes above goaf to the virgin area present in lower seam. Stress distribution over chock shields was considerably affected when the face in upper seam reached 15-25m zone above the galleries in the lower seam. A clear influence of the presence of solid coal, galleries and goaf in lower seam was found in the loading of longwall panel in upper seam.

Jan 1, 2007

By Mohammed Sakr

The use of helical piles for permanent foundation applications has become a practical and feasible alternative to the traditional cast-in-place concrete or driven steel piles. Research and development, installation equipment and manufacturing improvements in the helical piling industry have led to this trend. Moreover helical piles are typically smaller in size and weigh less than traditional piles, and require relatively smaller equipment and therefore it is a cost effective option. The latter is a very attractive feature for foundations installed in remote sites across Alaska. This paper presents full-scale pile load test results of helical piles and driven steel pipe piles installed in a site located in Anchorage, Alaska. Four full-scale pile load tests were carried out including two axial compression and two uplift load tests. Both helical piles and driven steel pipe piles were installed and tested at the same site under similar conditions to provide a direct comparison. The results of the full-scale load tests indicate the superior performance of helical piles compared to driven steel pipe piles. This paper describes the pile installation and test setup, presents the test data, and discusses the results.

Jan 1, 2009

By Wellington Pereira Inácio, Fernando Wypych, Sergio Neves Monteiro, Artur Camposo Pereira, Rafael Marangoni

"The efficiency by which an applied load is transmitted from the matrix to reinforcing fibers in a composite depends on the fiber/matrix adhesion strength. This is determined as the interfacial shear strength, IFSS, which may be measured by means of pullout tests that measure the force needed to pull a single fiber out of a block of material simulating the composite matrix. Different techniques are used to perform pullout tests. The objective of this work was to characterize the IFSS of sisal fibers embedded in epoxy matrix through the determination of the critical length pullout curves. As the main results, a relatively small critical length was found for the sisal fiber/epoxy pullout specimens, corresponding to a weaker IFSS. This was compared to other results applying different pullout techniques. Scanning electron microscopy observation identified the mechanism responsible for the weak sisal fiber adhesion to the epoxy matrix.IntroductionSynthetic fiber reinforced composites is today one of the most successful class of materials with increasing industrial applications from house appliances to large airplanes like the modem Airbus 380. However, environmental issues are revealing serious drawbacks related to the fabrication, use and post-use discard of these composites. For instance, the thermoset polymer composite reinforced with E-glass fiber, known as ""fiberglass"" has an energy-intensive fabrication associated with a surplus emission of C02, which is responsible for global warming [1]. Moreover, the glass fiber is considered toxic and also causes long term pollution after being discarded."

Jan 1, 2011

By Adil Aledresse, N. Emre Altun, Bern Klein, Nuri Hmidi, Brent Hilscher

A study was conducted to investigate high gold grades in water lines and carbon fines collected from the Musselwhite gold recovery circuit. It was discovered that fine magnetic particles in the overflow from the carbon fines settling tank launder had high gold grades ranging from 2,000 to7,000 g/t. The -37 micron fraction had up to 17,000 g/t gold. Scanning electron microscopy revealed the gold was attached to the surface of iron particles. The objective of the study was to identify possible mechanisms that result in the attachment of the gold to the magnetic iron particle surface and to recommend process modifications that would reduce these types of gold losses around the carbon circuits. Solid and solution samples were collected from the gold recovery circuit and analysed. Two possible mechanisms were identified including gold cementation onto iron and heterocoagulation of colloidal gold onto iron oxides in the elution column. Possible sources of the colloidal gold include reduction of gold cyanide complex to metallic gold in the carbon regeneration kiln and gold detached from cathode in EW cell. Based on SEM+EDX, the sources of iron were natural magnetite and roasted iron sulphides. Thermal reduction of gold is believed to be the cause of dendritic gold from the carbon regeneration kiln.

Jan 1, 2014

By N. Charue

An international prediction event was carried out within the framework of a 30-pile testing program organized in a sandy soil in Belgium (Limelette). That program called upon sev­eral testing methods: static load tests, Statnamic testing, and dynamic testing. This paper provides a summary of received predictions and results obtained from the static pile load tests, which were carried up to failure of the instrumented piles. The comparison between predictions is made using load-settlement curves with reference to the results of the static load tests. The predictions are based on a geotechnical approach using an extensive soil investigation program and a dynamic approach using the dynamic load test data.

Jan 1, 2002

By Walter D. Holland

This is one of a series of instruction guides developed to help instructors present health and safety training courses to workers in the coal mining industry. This course is intended for training those, usually the safety officers, who perform surveys fur inhalation contaminants in above ground work areas. The handbook entitled ?Handbook for Surveys of Inhalation Contaminants in Above Ground Coal Mining and Processing Work Areas? (NTIS #PB-243-35";) is used as a manual for the course and as a prime reference when performing the actual surveys or interpreting the sampling results. There are six experiments for the students to perform during the course to familiarize them with the sampling devices routinely used during the surveys.

Jan 1, 1976

"The 34th International Conference on Ground Control in Mining (ICGCM) was held July 28–30 at the Lakeview Golf Resort and Spa in Morgantown, WV. Ground control experts have gathered at this location since 1981 to share ideas and successes for improving designs and technologies to enhance the stability of surface and underground mining operations. Ground control is important to all mining operations but is particularly crucial to underground mining to ensure miner safety and operational viability.The year’s event had 240 registered attendees with 20 pecent of that attendance being from the mining industry. A remarkable number of industry representatives attended given the challenges currently faced by the mining industry. A true testament to the value of the conference, the performance of Tom Barczak and Steve Tadolini as co-chairs and the drawing power of the many exceptional speakers that have attended the annual event for many years.The conference operates under the direction of a board of directors with the cooperation, wisdom and assistance of a large organizing committee. Visit the conference website, www.icgcm.conferenceacademy.com, to view the membership of the board and the committee and to access previously published papers."

Jan 1, 2015

By M. M. Singh, J. W. Brown

Three rocks of highly varied physical properties are selected for the first reported experimental study concerning microseismic activity of rock under tension to determine the effects of static fatigue, loading rate, repeated loading and rock anistropy compared to compression and bending loads. The microseismic method of detecting rock under deformation may be a great potential tool in surveillance and location in situ of dangerously stressed strata, as well as predicting rock failures. Noises emitted under load or the rate of energy (energy of noise pulses generated per unit time) are computed for varying conditions. The tests are conducted at constant load on a dead weight loading machine to eliminate all possible extraneous noises — an indispensable precaution — at various load levels. Experimental results are reported including the relation of total energy emitted to tensile strength of rock and the possibility of simulating a phenomenological model for microseismic activity. Plots of some of the experiments are included. INTRODUCTION Rock failure, whether on a large scale faulting in the earth's crust and rock bursts in mines, or on small scale ruptures of laboratory test specimens, generates transient vibrations in the rock mass. Mechanisms of intermittent deformation, such as twinning and cracking through and between mineral grains, also produce similar vibrations, but of very small amplitude. Such vibrations from both deformation and failure are referred to as microseismic activity, rock noise, or occasionally seismo-acoustical activity. An individual rock noise is sometimes

Jan 1, 1967

By C. M. Weld

(Cleveland Meeting, October, 1912.) IN the course of my professional work in China during the fall of 1907, I had an opportunity to visit the iron-ore mines at Ta-yeh in Hu-pei province (long. 114° 50' E., lat. 30° 20' N.). It occurs to me that a rescript and discussion of my notes taken at that time should be of interest, particularly as supplementing the exceedingly interesting recent paper-of Thomas T: Read on The Mineral Production and Resources of China.1 Ta-yeh is situated near the right bank of the Yangtze river. The mines are at an average distance of about 16 miles from the river-port Shi-hui-yao, which in turn is some 70 miles S-E. of Hankow. The ores are shipped to the works of the Han-Yeh-P'ing Iron & Coal Co. at Hanyang, as also very largely to the Japanese government iron- and steel-works at Wakamatsu, Japan. Smaller quantities have been exported to the Pacific coast of the United States. These ore-deposits have been briefly noticed in a number of publications, but, so far as I know, Mr. Read's description, in his chapter on the iron-ores of the Chinese Empire,2 contains the first attempt to define their geological character. In his more recent paper Mr. Read follows very closely the text of his earlier description. To quote briefly from the recent paper, he says : " The iron-ores at Ta-yeh . . . . lie along the contact between a marble and an intrusive body of a dark-gray syenitic rock." He refers to a figure which exhibits in plan, but not in section, the relative positions of the syenite, ore-bodies, and limestone. The contact is seen to trend approximately E-W., with the syenite on the north and the limestone on the south. " The syenite lies to the north of the marble, and a few miles farther north the marble again' appears, iron-ore again being present along the contact." No litho- 1 Bulletin Bulletin No. 63, March, 1912, pp. 293 to 343. 2 The Iron Ore Resources of the World', vol. ii., p. 913 (Stockholm 1910).

Oct 1, 1912

Rockbursts continue to be a scourge in the mining industry, being responsible for accidents and damage to mining excavations. Although the problem has been present for more than a century, and although much research has been carried out, a solution is still elusive. Determination of, firstly, the demand on the support system imposed in the rockburst and, secondly, the capacity of the support system, cannot be carried out with any confidence, and therefore rockburst support cannot be designed using a conventional design approach. In contrast with the conventional approach, observations of rockburst damage in a mine have revealed a possible alternative approach to rockburst support ? sacrificial support. It was observed, in rockburst events, that a support system consisting of concrete panels restrained by grouted cables was destroyed, and the concrete panels were ejected. However, the rock behind the panels remained apparently undamaged and in place. This behaviour reignited the concept of sacrificial support, conceived more than 20 years ago, and which is described in this paper. The remedial solution implemented on the mine, involving cables wrapped over the panels and retained by grouting into boreholes, has been subjected to rockburst loading and has confirmed the validity of the sacrificial support concept. The concept of sacrificial support may be controversial, but is deliberately presented here with the aim of generating discussions and contributions, and with the ultimate aim of improving safety and reducing rockburst damage in mines. Keywords rockburst, seismicity, seismic waves, rock support, support design.

Jul 1, 2013

By K. Moxham, R. G. B. Pickering

Over the last few years Lonmin Platinum and Sandvik have embarked on a unique partnership of collaboration through a systematic approach to developing equipment to mechanize and automate narrow reef platinum mining. After the initial design and manufacture of the equipment the key aspect is the integrating equipment, people and method into a mining system. Another key a spec of mechanization is the optimization of equipment utilization and this philosophy has ensured continual evolvement of mining methods. This paper describes the trials and development that have resulted in the mining method described as Lonmin mechanized breast.

Jan 1, 2006

By Corby G. Anderson

"Laboratory testing, plant optimization, and the interpretation and application of metallurgical technologies can be tedious, time consuming and costly. This paper outlines the use of proven statistical design of experimentation software for rapid laboratory testing and optimization of operating plants with limited representative sample utilization. This results in less costly required testing, a more thorough understanding of results and the ability to simultaneously optimize several variables and outcomes at once. At the Center for Advanced Mineral and Metallurgical Processing (CAMP), this testing methodology has been used successfully in many metallurgical development and plant optimization projects thereby confirming its real world utility and application. Accordingly, several applied examples in flotation and hydrometallurgy will be outlined in this paper. This will include flotation testing of a copper gold ore, flotation testing of a copper, cobalt and gold ore, optimization of an industrial hydrometallurgical jarosite circuit and optimization of industrial nitrogen species catalyzed pressure leaching of a copper enargite concentrate.INTRODUCTIONWhile flotation technology is now 100 years old, the testing, interpretation and application of lab results can be tedious, costly and time consuming requiring extensive sample collection and preparation. In addition, recent applications like hydrometallurgical pressure leaching and associated unit operations, such as precipitation, still remain more of an art than a quantifiable science. This paper will elucidate the application of STAT-EASE Design-Expert software to minimize required laboratory testing while rapidly optimizing multiple results and outcomes in a statistically valid manner. The STAT-EASE program is based on proven design of experiment fundamentals. In this paper, the real world application of this methodology for lab testing, plant optimization and process development will be elucidated."

Jan 1, 2006

THE slide-rule, as a quick and convenient instrument for performing approximate calculations, is steadily growing more and more into favour with the engineer, and results obtained by it are considered close enough to enable him to satisfactorily dealwith a considerable portion of his work. To the surveyor, however, whose ordinary computations must be as precise as his measurements, the present makes of rule are insufficient, except for a very narrow margin of the scales and for rough work. Few will carry the rule when they can clearly see that it is unreliable for general routine, and the careful surveyor is inclined to look askance at those who do use it, recognizing the temptation there undtmbtedly must be to push it into work that the log book should be called upon to treat. From the fact that a surveyor's duties take him on the surface in all weathers, and underground in many wet and uncomfortable places, where the manipulation of a book of mathematical tables becomes both awkward and patience-trying, an efficient slide-rule must offer the mbst transparent advantages. Again, a surveyor being specially trained to read divided scales quickly and accurately, the slide-rule must commend itself as an apt addition to his outfit.

Jan 1, 1912

By E K. Leeka

Process control limitations have led to suboptimal performance of the crushing section of Sishen MineÆs Jig Plant. The performance of the PID (proportional-integral-derivative) controller implemented during commissioning was hampered by the relatively small buffer capacity between the crushers and screens. The inability to maintain the tertiary crushing chamber under full choke conditions lead to inefficient crushing and reduced crusher product cubicity.Model predictive control (MPC) was implemented in the tertiary crusher plant in May 2012 and resulted in a throughput improvement of six per cent in its first month. The controller was further optimised and indicated a throughput improvement of 16 per cent during on/off testing in July 2012. The throughput improvement is attributable to the finer crusher product resulting from operating the crusher under full choke conditions and controlled feed rate to the tertiary crusher plant screens. The next step is to couple the model predictive controller, automated gap control system and an economic optimiser to ensure maximised throughput and value from the resource.CITATION:Leeka, E K, 2013. Performance of model predictive control on the crushing circuit at Sishen Mine, in Proceedings Iron Ore 2013 , pp 417-420 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

By O. T. Barrett, R. F. Aberethy, H. N. Cooper, Thomas Fraer, William L. Crentz

"INTRODUCTION The object of the techniques described in this report is to determine the possibilities of separating the components of a raw coal into such grades as may be necessary to recover some exceptionally clean functions for special purposes.To do this commercial gravity methods would require separation at very low specific gravities, entirely outside the range of conventional practice. Hence, a technique has been developed for breaking down cool ample, into very close fractions within the gravity range of the (-lean coal matter as well as for separating it from the refuse and particles.Such data on the fundamental specific-gravity consist of the clean-coal matter will serve to appraise the difficulty of the problem and to chow be accomplished if and when effective methods of making such separations commercially are developed."

May 1, 1945

By Ali Mortazavi

In underground mining applications, successful blasting results in less damage, which may lower support costs, lower dilution and produce a uniform fragmentation. The explosive detonation process creates a pressure front that propagates a stress wave into the surrounding rock mass at a high velocity. The stress wave can induce varying degrees of damage, depending on rock strength and physical properties, to the excavated area. This paper presents a summary of a research project that was conducted to investigate the propagation of explosive-induced stress waves in hard rock media and the mechanism of rock damage and fracturing due to shock wave propagation. The primary objective of this work was to numerically simulate the experimental study of blast-induced rock fracturing conducted within Inco Limited, Mines Research department. ITASCA?s discontinuum code UDEC (Universal Distinct Element Code), was used to simulate the results of the controlled blasting experiments. In brief, the focal point of the paper can be summarized as follows: ? Investigate the size of the stress-wave-induced fractured zone around the blasthole, ? Examine the extent and direction of the radial fractures that form outside the blasthole, and ? Explore the mechanisms that cause rock breakage.

May 1, 2002