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By Kirstin Girdner, Tom BoBo, Brian Norton, John Kemeny

Split Engineering is a truly customer oriented company dedicated to providing quantified fragmentation information of the highest integrity to enable process management and control. Technical decisions, blasting costs, operational efficiency and productivity and equipment performance can all be related to optimum fragmentation. In the past, the lack of an easy, non-disruptive, economical measuring technique has meant that, in most cases, rock fragmentation has not been defined in quantitative terms. Now, the Split-Desktop@ software provides an economical alternative to manual sampling and screening and an objective measure rather than subjective qualitative estimates. This workshop will present the latest features of the Split-Desktop@ software and show users how to quickly get quantifiable results from their blast fragmentation. A step-by-step demonstration will display the software’s flexibility, user-friendly options, and ease of use. Outlining where other mines have benefited from using the Split-Desktop@ software will provide insight to a wide range of software uses and potential applications like creating a database of geologic zone specific post-blast fragmentation information, underground draw point monitoring, stockpile, leach pile, and waste dump size measurement and monitoring, as well as many other applications.

Jan 1, 2000

By Raymundo Del Carpio

El presente trabajo señala las bases que fundamentan la aplicabilidad del extracto de quebracho como depresor en el proceso de flotación, donde se realiza una combinación de un dispersante (producto obtenido a partir de extractos vegetales). También se muestra los avances sobre procesamiento de minerales con alto contenido de pirrotita. En ese sentido, se busca desarrollar una tecnología eficiente y ambientalmente limpia, considerada como una herramienta para la mejora de la competitividad de la empresa, a partir de una visión de desarrollo sostenible.

Sep 9, 2007

By C. McCall, J. T. Knight, J. R. Ridley

Gold mineralisation in the gabbro sills is mainly stratabound to quartz- and Fe-rich, granophyric-textured units and is sited in undeformed, brittle quartz vein sets, which form pipe-like orebodies. Hydrothermal wallrock alteration consists of hornblende-plagioclase-calcite-quartz with minor biotite, garnet and chlorite and with arsenopyrite and pyrrhotite as the dominant sulphides. Geothermobarometric data suggest that gold was deposited at around 520 degrees C at 2.8-3.8 bar. Mineralisation is thought to have occurred during amphibolite-facies metamorphism. Fluid inclusion and isotope data indicate that gold mineralisation was the result of deposition from a low-salinity H2O-CO2-CH4 fluid of either metamorphic or magmatic origin. Although the Three Mile Hill deposit differs from others in the area in its wallrock-alteration assemblages, peak-metamorphic timing of gold deposition and distinct geochemical associations it forms a brittle stratabound ore body which suggests structural and gold-depositional mechanisms in common with those of the other gabbro-hosted gold deposits

Jun 18, 1905

By R. D. Leitch

"INTRODUCTION The character of mine drainage from areas of low pyritic coal3 and from average pyritic coal4 has been investigated, and to complete the study it seemed desirable to select a number of mines situated in high pyritic are as to determine whether or not this variation determines the relative acidity of drainage from mines operating in these characteristic coal fields. Advantage has been taken of some worked on in 1918 by Henry Leighton 5, then Professor of Economic Geology, University of Pittsburgh. He visited and has reported certain areas of high pyritic coal which we also visited during this study. Many of the mines were found to be idle in 1930 and a few were caved shut, apparently for several years. However, samples of the outflow from all mines visited were collected if possible and analyzed, and some general information was gathered for each mine. The map (fig. 1) shows the location of these areas as given by Leighton.ACKNOWLEDGMENTSThe information and assistance obtained from officials and others at the mines visited during this study are gratefully acknowledged, as well as the original suggestion from Dr. Glenn V. Brown of the State Sanitary Water Board who called attention to the desirability of such a study.Thanks are also especially due the coal laboratory of the United States Bureau of Mines, under the direction of H. M. Cooper, for the analyses and determination of sulphur forms in the large number of solid samples necessary to the work reported,This study has been carried on under the direction of R. R. Sayers, chief, health and safety branch, and W. P. Yant, supervising engineer, Pittsburgh Experiment Station, of the U. S. Bureau of Mines."

Jan 1, 1932

Large scale fluid extraction from the Latrobe Group in the Gippsland Basin is occurring as a result of offshore petroleum production and coal mine dewatering in the Latrobe Valley. Groundwater extraction in the Latrobe Valley exceeds recharge and is causing an expanding area of declining hydraulic head in the Latrobe Group, and regional land subsidence which is well documented. Recently the government water sector completed the installation of a network of Latrobe Group monitoring bores in the remainder of the onshore part of the Gippsland Basin. The bores situated along the coastal area show a steady decline in hydraulic head of about 1 m/year which can be attributed mainly to petroleum production.

Jan 1, 1992

By Tim O’Neil

If you build a big truck, build a big tire to match it. Let that haulage synergy aid the economics, productivity and lessened maintenance for the unit. Now, Cater-pillar and Michelin have done just that. Discussions began in 1996. Caterpillar was making plans for its 797 ultra-class haul truck. The development team realized the need for a tire that could withstand extreme loads. The 797 would weigh 558 t (615 st) and be capable of 64 km/h (40 mph) speeds. So Caterpillar approached Michelin. The two companies realized the benefits of jointly developing a tire for the 797.

Jan 1, 2002

By E. A. Magill

This report is one of a series prepared by the Bureau of Mines on manganese deposits of the Northwestern States. It describes properties on the Olympic Peninsula, Wash. Exploration by the Federal Bureau of Mines in 1939-40 and 1954-55 on several typical deposits is summarized, and examination data are presented for other manganese deposits on the peninsula. An attempt was made to list all known occurrences; however, some properties are abandoned, and their exact location is unknown.

Jan 1, 1960

By D. B. Taliaferro

[Recovery of core specimens from subsurface formations and their subsequent analysis are important aids in efficient development and operation of oil and gas fields. Core specimen first were obtained mainly for the geologic information they revealed; now they are on analyzed to determine many of the physical characteristics and conditions of the subsurface formations as well. Cores recovered from the producing formations may be analyzed for porosity, permeability, oil content, "connate" water content, and other physical and chemical properties of the formation, all to the end of furnishing enough data for making reliable estimates of the quantity and availability of oil and gas within reservoir and in devising efficient means for their withdrawal.]

Jan 1, 1939

By Kazunori Matsushita, Frank Vespi, Emi Walder, Mitsuo Nozu

During the runway expansion project at the Fort Lauderdale-Hollywood International Airport in Florida (FLL project), therewere complicated geotechnical issues with a number of cavities in the limestone-loose sand mixed ground thatexisted in many areas below the existing ground. Collapsing the cavities and compacting the runway foundation to secure the take-off and landing of aircrafts was a necessary requirement for the project. The Mammoth Vibro-Tamper (MVT) which produces less vibration and noise level, was proposed and accepted as the alternative to the originally specified Deep Dynamic Compaction (DDC) for the runway with its length of 1.5 miles and area of 570,000 square yards. In this report, the shallow compaction effect and reduced ground vibration with the MVT are presented in comparison with the DDC which was utilized on the same project in a different area of the airport. INTRODUCTION MVT was developed by Fudo Tetra Corporation in the 1960’s and has been widely used in Japan (more than 14,400,000 square yards). For example, at the Kansai International airport, a large area including aprons was compacted with the MVT. It is capable of compacting up to approximately 5m in depth by using a heavy steel plate (3m x 3m) and a strong vibrator motor (V-180, 10Hz) on top of the steel thick plate with specified time duration. We were involved in densification work with the MVT at the Fort Lauderdale Airport Project (Figure 1) from June, 2012 to February, 2014. Deep Dynamic Compaction (DDC) was originally specified as the compaction method to secure the relative density over 70% in every 2,000 square yards grids, however, we proposed the application of MVT to reduce the vibration risk and it was accepted as the alternative (Figure 2). The compaction work was completed in February 2014, without causing any delay in regard to the residual settlement due to the high embankment (H=60ft=18m).

Jan 1, 2018

By Douglas Brittsan

This paper presents pile tension and compression load test results for the Southern Freeway Viaduct (North) pile load test site. The testing program represents a collaboration between California Department of Transportation (Caltrans), Federal Highways Administration (FHWA), and a group of pile manufacturers and construction firms. The participating manufacturers included Fundex, Halliburton, Monotube, and Nicholson, with each firm supplying proprietary pile systems. The field test program measured and will allow the direct comparison of the tensile and compressive capacity of nine common and proprietary pile systems installed in nearly identical soil conditions. Data reported here-in details pile compression and tensile load-deformation measured at the pile head. Cursory data regarding pile installation details are included to aid in data interpretation.

Jan 1, 1993

By Trevor L. L. Orr

"AbstractThe background to the harmonization of geotechnical standards that has taken place in recent years in Europe has been the move to more economic and political integration following World War II that has led to the formation of the European Union. Prior to 2010 the standards used in the European countries for geotechnical design, investigation and testing and for the carrying out geotechnical work, such as the installation of piles, were the different national standards, which were not harmonized. The harmonization of geotechnical standards in Europe started in 1981 with work on a model Eurocode 7 for geotechnical design that led eventually to publication by CEN, the European Committee for Standardization, of the European Standard version of Eurocode 7 in 2004. In parallel with the work on Eurocode 7, a large number of associated harmonized standards have been, and are being, prepared by CEN and by the International Standards Organization (ISO) for geotechnical investigation and testing and for the execution of geotechnical works. Standards published by CEN must be adopted by the CEN member countries and all conflicting standards withdrawn. Hence all the CEN countries have adopted the same the harmonized text of Eurocode 7, but with National Annexes that allow national choice with regard to Design Approach and partial factor values. The adoption of Eurocode 7 and its associated geotechnical standards has removed the barriers to geotechnical activity in Europe due to the presence of different national standards. It has also enhanced the ability of EU firms to compete in the global market.Background to harmonization of geotechnical standards in EuropeThe initial moves towards the harmonization of geotechnical standards in Europe can be related to the economic and political developments that took place in the period immediately following World War II to revive the economies of Western Europe. Europe at that time was divided by a political and, in many places, a physical barrier, known as the Iron Curtain, into two very different and separate zones: communist in the east and non-communist in the west. In 1952 the European Coal and Steel Community (ECSC) was formed, linking 6 countries: Belgium, West Germany, France, Italy, Luxembourg and the Netherlands, and establishing a common market in coal and steel. The ECSC was the first international organization to be established on the basis of supranational principles whereby negotiated power is delegated to an authority by the governments of the member states. In 1957 the ECSC became the European Economic Community (EEC), also known as the Common Market in the English-speaking world, with the aim to bring about economic integration. With the addition of Denmark, Ireland and the UK in 1973 and Greece in 1981, followed by Portugal and Spain in 1986, this led to the formation of the European Union (EU) in 1993. East and West Germany were reunified in 1990, following the fall of the Iron Curtain in 1989. In 1995, Austria, Finland and Sweden joined the EU, and since then the numbers of countries in the EU has increased to 28, many of which are countries that were formerly behind the Iron Curtain."

Jan 1, 2014

During August, 1926, with the consent of Mr. Schell, mine manager, the writer conducted a mill test on this company's concentrators. Mr. Schell not only gave him his permission, but rendered all possible assistance. Although it was impossible to take all the samples one could have wished to obtain, yet the salient points of the mill flow-sheet were sampled for a continuous period of eight hours, and from these samples and separate data supplied by the manager, valuable information was collected.THE MINEThis is a true vein-type of mine; the lode formations, striking almost due north-south, cut the large porphyritic intrusion at right angles. There are three distinct veins on this property - parallel, persistent, and dipping at an angle varying between 40° - 50° to the horizontal.The country rock is very sound, and timber, save for the small amount required for ore chutes, is entirely absent from all mine workings.The lode varies from a width of 1 in. to 8 in., but the stopes are carried forward with a minimurn width of about 30 in.The mine is particularly dry for a West Coast property, and conditions underground are very favourable. Air drills are used...

Jan 1, 1928

By Gray Mullins

This paper presents results from model and full-scale tests to assess the interface bond between a cast-in-place concrete seal slab and steel H-piles in cofferdams. Three different seal slab placement conditions - fresh water, salt water and bentonite slurry - were evaluated and the results compared against controls where no fluid was displaced by the concrete. Normal pile surfaces were investigated. Additionally, the situation of ?soil caked? piles was also tested. In the model tests, eight 15 cm deep, W6 x 15 sections were used for two different embedment depths of 1.5d and 2d, d being the depth of the section. In the full-scale tests, 16 specimens 35 cm deep (W14 x 90 sections) were tested with the embedment varied between 0.5d-2d. The results show that significant bond stresses developed even in the worst placement condition. Recommendations made for revising current values in specifications have already been implemented by the Florida Department of Transportation.

Jan 1, 2013

By Tristan Worsey, Nathan Rouse, Kyle Hall

Drilling accuracy is the foundation to any successful blast operation. Even the best blasting practices cannot overcome poor drilling and still obtain desired results. Inaccuracies in boreholes can result in flyrock, increased vibration, uneven floor, and other undesired effects. As depth increases, variation in actual burden and spacing is expected even if collars are located precisely. Problems arise when this deviation reaches a point where it adversely affects the function of the blast design. Not only can unsafe conditions such as insufficient burden at the face develop, but poor fragmentation can compound adverse effects. As with any troubleshooting, problems cannot truly be fixed if they cannot be measured. As a result, significant work has been done in the past on this subject. Currently, there are both cheap and expensive methods used to quantify deviation for a given borehole. However, implementation of these techniques is limited. In general production blasts, little is known about the variance in designed versus true borehole geometry. This is especially true if the blaster does not see telltale signs of drilling deviation. However, losses in blast performance may exist and provide an opportunity to obtain better fragmentation and reduce fines. As drill and blast operations strive for better optimization, greater focus is being placed on drilling accuracy and solutions to this problem. The following paper details the use of several current methods for deviation measurement in order to help prevent compromises of safety and improve overall blast performance.

Jan 1, 2018

By G. F. Butterworth

The metallographic structures most frequently encountered in rifle barrels, and which are illustrated by the accompanying photomicrographs, fall naturally into two groups, distinguished by the method used to, produce in the stock a physical condition having the requisite properties. The fist group consists of "rolled" barrels; that is, barrels subjected to hot working by rolling in or near the critical range. In the second group, the stock, which is smaller in diameter than the first, is upset to form the butt end and is then heat treated by giving it a quench and a draw. These barrels will be referred to as " heat-treated " barrels. The structure of the rolled barrels resembles closely that of the same steel after annealing. There is the same network of excess ferrite outlining the grain boundaries, but the grains themselves are composed of sorbite rather than pearlite. The grain size is closely related to the rolling temperature. The critical-point curves of this grade of steel, which is approximately 0.50 to 0.60 per cent. of carbon and 1.00 to 1.30 per cent, of manganese, show a single very pronounced point between 1300" and 1350" F. (704" and 732" C.). Barrels rolled within this temperature range give an exceedingly fine grain, shown in Fig. 1. In fact, the grains may be so fine that, at a low magnification, they may be confused with the heat-treated structure shown in Fig. 6. A magnification of 500 diameters, however, will always resolve a rolled barrel into the characteristic structure shown in Fig. 2. As the temperature is increased, the grains are found to be larger. If, on the other hand, the rolling temperature is below the critical range, the structure previous to rolling will not be obliterated, the only effect of rolling being to elongate the coarse sorbite grains in the direction of rolling, Fig. 3. This distortion is greatest at the muzzle. Heat-treated barrels are quenched in oil from above the critical range, which should give a martensitic structure, Fig. 4, but the presence of some troostite in the martensite is frequently noted when the quench has not been sufficiently drastic, Fig. 5. The structure brought about by the subsequent draw is not so striking, though quite as typical. It is sorbitic or sorbito-pearlitic, and under a low magnification appears almost homogeneous, as in the case of fine grains of pepper and salt well mixed together, Fig. 6. This structure is substantially the same for all

Jan 1, 1920

By A. C. Fieldner

Much activity is called for in the present period of hightened national effort, and wise direction of such a program must always be conditioned by positive knowledge gained in years of slow and painstaking study and development. Research and technologic investigations on coal by the Bureau of Mines have been described in a series of annual

Jan 1, 1941

By S. Constantinides

Over the past 100 years we have witnessed a revolution in permanent magnetic materials. Prior to 1932 electrical machinery depended upon steels for both the soft and the permanent magnet structures. Because permanent magnet steels were easily demagnetized, motors, generators, loudspeakers and similar devices often used the interaction between two electromagnets. Motors and generators were mostly of the induction type, depending for function upon induced fields. The discovery of Alnico in 1931 and its rapid commercialization presaged an expansion of the industrial revolution and today, permanent magnet structures are widely utilized. [ ] DEVELOPMENT OF PERMANENT MAGNETS Act 1: Early Days of Permanent Magnets Alnico, which stands for aluminum, nickel and cobalt, is a family of alloys with similar structure and processing requirements. Additional elements, such as copper and titanium, are present in minor amounts to optimize magnetic properties. Alnico is known by many trade names around the world including Alcomax, Hycomax, Ticonal, Nipermag, Koerzit, Oerstit, Nialco, etc(1,2,3). In addition to the generic name ?alnico?, it is usually appended with a number representing the magnetic grade.

Jan 1, 2011

These proceedings consist of an introduction and four descriptive papers. The first paper is an update on fire protection for large haulage vehicles, the second paper is concerned with improved visibility systems for large haul- age vehicles, the third paper is on improved ladders for large haulage vehicles, and the fourth paper is concerned with large haul-age vehicle operator training systems.

Jan 1, 1980

By R. L. Marek

"The number of persons fatally injured in the petroleum industry in California in 1930 was 50, a decrease of 20.6 per cent from 1929, when 63 men accidentally lost their lives. The decrease in the number of fatalities for 1930 has caused the first downward trend in the fatality curve of the California petroleum industry since 1927 and is coincident with a period of little active development in new fields, the shutting in of many wells, and reduced activity in the older fields of the State. That a direct relationship exists between the number of accidental deaths and the rapidity of new field development is particularly emphasized by the fact that in 1929, a year of intensive field development in California, 48 men were killed in the drilling and producing division, whereas in 1930, a year of less development work, only 25 men were killed in this division,The figures for the average number of drilling and producing wells in 1930 decreased appreciably from comparable figures for 1929 and a greater percentage of producing wells were shut—in in 1930 than in 1929."

Dec 1, 1931

By I. C. L. Webster, G. E. Ray

"The magnetite-rich Heff Cu-Au skarn lies in the Quesnel Terrane of south-central British Columbia, approximately 26 km northeast of Kamloops. The skarn formed close to the northern margin of the Heffley Creek pluton, and is hosted by Carnian (Late Triassic) Nicola Group limestone. The Late Triassic pluton (208.1 ± 6.1 Ma, U-Pb zircon) is a composite body of alkaline affinity that includes dioritic, gabbroic, and magnetite-rich clinopyroxene ± olivine ultramafic phases.The skarn has been discontinuously traced along strike for more than 1 km, and individual skarn layers are up to 40 m thick. The most common non-opaque minerals are garnet, clinopyroxene, and carbonate, with lesser epidote, biotite, amphibole, and chlorite. Apatite locally forms more than 3 vol.% of the rock. Compositionally the garnet is a low Mn grandite averaging Pyr3-Grs41-Adr56 mol.%.Mineralization consists of lenses, up to 10 m thick, containing massive low Ti-V magnetite (avg. 0.03 wt.% TiO2 and 0.01 wt.% V2O3). Magnetite is associated with up to 20 vol.% pyrrhotite, lesser pyrite, and trace chalcopyrite and gold. There is a moderate enrichment in rare earth elements with assays up to 570 ppm La and 490 ppm Ce. The Heffley Creek pluton belongs to a suite of Late Triassic-Early Jurassic alkalic and Fe-rich intrusions that are widely developed throughout the Quesnel Terrane. Some host Cu-Au porphyry mineralization, but less commonly they are associated with magnetite-apatite veins such as at the Glen Iron mine and Magnet occurrence, or with magnetite-rich Cu-Au skarns such as the Heff occurrence.Although abundant low Ti magnetite is present in the Heff skarn, it does not appear to represent iron oxide copper- gold (IOCG) type mineralization. Microprobe analyses completed during this study show that low Ti magnetite is not a unique feature of IOCG deposits, but also characterizes some other types of hydrothermal mineralization. In British Columbia these include some alkalic porphyry-related magnetite-apatite veins in the Quesnel Terrane, as well as the well-known Wrangellia-hosted Fe skarn deposits. Thus, low Ti magnetite appears to be a common signature of many magmatic hydrothermal deposits in contrast to the high Ti primary magnetite found in most igneous rocks."

Jan 1, 2007