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Many block caving operations experience difficulties during undercutting, resulting in draw horizon damage, production loss and extensive drift repairs for the life of the block cave. This paper deals specifically with block cave undercut aims strategies, methodologies and management to avoid the problems indicated above.

Jan 1, 2000

By Philip B. Bucky

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Jan 1, 1942

Block caving is the lowest cost underground mining method but it has relatively high risks and a high up-front capital and development cost. It has application to large, often lower-grade orebodies where high production rates can provide good returns on the investment. However, it has a range of technical risks that are peculiar to block caving and the usual financial, political and environmental risks that may be exacerbated by the long lead-in times associated with the development of a block cave operation. With initial development costs that may be $100 M to $1000 M when the building of a treatment plant is also required, it is obviously important to minimise and manage the risks. In a greenfield project, commitment to a substantial proportion of the capital expenditure may be required to gain access to the deposit, and the decision to proceed at this stage would be based very largely on interpretations of drill hole data. In established mines the data may be supplemented by geological mapping and past experience, etc. The quality of this data is critical and yet it is frequently degraded through poor techniques and avoidable omissions. The final decision to proceed would be assessed on projected commodity prices, mining capital and operating costs, dilution and run of mine ore grades. The latter will vary over the life of the project and these can be estimated with drawdown or draw control modelling techniques. In this modelling, there are further risks in the assumed modelling parameters or that the modelling technique may not be applicable or appropriate. The paper addresses the most critical technical and operational risk areas and provides some practical precautions that can be taken to reduce these and improve the reliability of the geological and geotechnical models.

Jan 1, 2000

By Philip B. Bucky

[CONTENTS t. How Does One Determine WhetherPAGE an ore Body Will Block-cave?R. W. Hughes13 Sherman R. Burdick 13 PAGER. T. Gallagher 14 Mark A. Smith 2 C. F. B. Price, Jr.14 Harry A. Leidich2Benjamin F. Tillson 14 McHenry Mosier2C. F. Jackson14,17 R. W. Hughes2R. Taborelli15 Sherman R. Burdick3Frank A. Ayer16 R. T. Gallagher 3Philip B. Bucky16 Benjamin F. Tillson 3Rollin Farminr6 Lucien Eaton 3J. L. G. Weysser15, 0,17 C. F. Jackson 3George S. Rice17 Philip B. Bucky32. How Does One Determine the Block4. What Determines the Procedure in Dimensions and the DevelopmentRemoving Caved Ore? Work Necessary to Make an OreHarry A. Leidich17 Body Cave?McHenry Mosier17,21 Mark A. Smith 5,7,() R. W. Hughes17 Harry A. Leidich6Sherman R. Burdick 18 McHenry Mosier6,7,12 R. T. Gallagher 18 R. W. Hughes6Mark A. Smith I8 Sherman R. Burdick 7Philip B. Bucky20, 21, 23 R. T. Gallagher 7C. F. B. Price, Jr20 Benjamin F. Tillson 7,11R. H. Bennett21 L. E. Young7C. F. Jackson 21, 23 Robert D. Hoffman8, 1 2Gerald Sherman 3 . 21 Gerald Sherman8Tell Ertl21 Philip B. Bucky10, 11, 12G. K. Foster 23 R. S. McClellan 12C. H. Shoemaker23 Tell Ertl 12 3. How Do the Forces Act and What Are5. What Are the Criteria for Determining the Stresses Developed in a Blockthe Efficiency of a Block-caving That Cause It to Block-cave?Operation? Mark A. Smith 12, ISHarry A. Leidich23 Harry A. Leidich13McHenry Mosier24 McHenry Mosier13R. W. Hughes24 Sherman R. Burdick 24 R. T. Gallagher 24]

Jan 1, 1942

By Ray L. Tobie, Douglas E. Julin

GENERAL DESCRIPTION Block caving is a distinct caving method applied mostly to large, massive, ore bodies because of its in¬herent low cost and high production capabilities. Areas of sufficient size are removed by undercutting so that the mass above will cave naturally. Drawing of the caved ore at the bottom of the ore column causes the caving action to continue upward until all of the ore above the undercut level is broken into sizes suitable for handling. When properly applied, block caving results in a lower mining cost per ton than any other under¬ground method. There are three distinct forms: (1) dividing the horizontal area into rectangular or preferably square or nearly square blocks, drawing evenly over the entire area to maintain an approximately horizontal plane of con¬tact between broken ore and caved capping; (2) divid¬ing the horizontal area into panels across the ore body, retreating by undercutting manageable areas from one end of the panel to the other and maintaining an in¬clined plane of contact between the broken ore and caved capping (thus the name panel caving); and (3) no division of horizontal area of the ore body into defi¬nite blocks or panels (this is termed mass caving). Undercutting may be from wall to wall, retreating from one end of the ore body to the other, maintaining an inclined plane of contact between the broken ore and caved capping. The total active caved area is deter¬mined by the size of block that will not produce undue stress on workings below the undercutting level and by total production requirements. This type of operation is also referred to as panel caving at some properties. SUITABLE ORE BODIES Block caving in its various forms is applicable to deposits of various shapes and ores of various strengths. Its success is governed by rigid requirements and limi¬tations. In unsuitable deposits or where improperly em¬ployed, the loss of ore may exceed that of any other mining method. Good planning, systematic work pro¬cedures, careful supervision, and good judgment con¬tribute to its success. Ore Characteristics Included as a necessary characteristic in an ore body suited to a successful block-caving operation is a proper fracture pattern. Ore hardness should be another gov¬erning factor, and the toughness or softness of the ore should be considered. There must be sufficient horizon¬tal area available for expansion of the undercut, if neces¬sary, to start the caving process. Large, massive, ore bodies usually meet these conditions. Veinlike deposits must be wide and dip rather steeply to conform to the block-caving limitations. The capping must be of such a nature as to cave when the underlying ore is being removed since the weight of the overburden aids in crushing the ore. The most favorable capping character¬istic is that it breaks into coarse pieces and resists attrition as the block is drawn. Soft capping, by breaking into fine pieces and sifting into the ore or channeling through the ore to the drawpoints, can seriously dilute the ore and hinder the extraction of clean ore from the blocks. Types of Ore In block caving, a fairly uniform distribution of val¬ues in the ore is necessary. Grade values may range from low grade to high grade, but most often the sys¬tem is applied to low-grade ores. Wide veins, thick beds, or massive deposits of homogeneous ore overlain by ground which will cave constitute suitable ore bodies. The ore must be such that it can be supported while blocks are being developed and undercut but breaks up readily when caved. Some applications include porphyry copper, disseminated molybdenite, hematite in the Lake Superior iron district, limonite deposits in northern Spain, the diamond mines of South Africa, asbestos and nickel in Canada, and massive magnetite in Pennsylvania. Size and Shape Outline of the ore body should be fairly regular, and the sides of the ore body should dip steeply. It may not be economical to mine small portions of ore extending into the walls of the deposit, and low-grade inclusions in the ore cannot be left unmined. Some dilution of the ore, as mining progresses, by low-grade or barren cap¬ping is inevitable and, unavoidably, some clean ore is left between drawpoints. Determining Cavability The use of rock mechanics is sometimes advantageous in helping to determine the cavability of an ore deposit. The US Bureau of Mines has information and testing ability which can assist in determining the cavability of ore types. Several competent consulting orga¬nizations knowledgeable in rock mechanics can also as¬sist in evaluating the cavability of an ore body. Some recent work has been done to better define the cavability index of various ore bodies; an example of how this was determined is discussed by McMahon and Kendrick (1969). The intensity of the fracture pattern is a critical parameter to be analyzed. The question to be answered is, "How intense must the fracture pattern be?" Table 1 is a tabulation of the size of rock fragments that appear at the drawpoint of various block-cave mines around the world. These are indicative of the fracture-pattern spac¬ing and, as can be seen, they vary substantially from the almost sandy material at the Mather mine to fairly sizable blocks at the Grace mine. Several sets of fractures are essential to promote good caving. Ideally, two vertical sets at nearly right angles to each other and a third set nearly horizontal are required to insure a good caving ore body. Since initial caving of an ore mass is almost always by the action of gravity acting on these planes of weakness, it is doubtful

Jan 1, 1982

By J E. Everett

Maximising ore tonnage at a selected target grade requires that appropriate ore identification criteria be established. Iron ore mining block models may consist of many millions of estimated blocks, each block corresponding to the selective mining unit (SMU), with grade interpolated from drill hole data. Each block can be considered as a potential ore candidate. Analysis of such a huge database can require large computational resources, especially for sensitivity analysis requiring multiple computations. However, an alternative streamlined approach is possible, where the data are compressed to an appropriately smaller and representative subset. The consequent data reduction not only makes it feasible to consider the simultaneous analysis of multiple pits but also considerably speeds up computation, enabling sensitivity analysis of the potential ore tonnage as a function of the required grade. Ore identification criteria can be successfully established using appropriately chosen reduced data comprising less than one per cent of the blocks. The ore identified is virtually indistinguishable in tonnage and grade from the ore that would be selected using the entire block model.Two methods of data reduction are tested: sampling (using a proportion of unaltered blocks) and binning (consolidating groups of blocks to a single average grade). The source blocks are first sorted (such as by location, analyte grade, principal component score, random order or value) before sampling or binning. In this study, the sorting options considered were by location and Fe grade. The effectiveness of each method was evaluated using the block model subsets to select the maximum tonnage of ore at a specified target grade. Block model data from an anonymous Pilbara iron ore project with about one million blocks averaging 1.132 kt were used. The blocks are from multiple resource models, to be blended to a single product. Sampling is shown to be superior to binning because sampling preserves the full variability while binning, although matching the mean block grades reduces their variability.It was found that the appropriately sampled data sets (sorted by location) gave results virtually identical to the results for the full data set, even when the samples comprised less than one per cent of the original blocks. The reduction in computer time to identify maximum tonnage at a specified grade was approximately proportional to the sample percentage. The increase in computation speed greatly facilitated sensitivity analysis. A sampled data set of one-eighth the total block model was used to investigate the effects of changing each of the component grades around the original grade specification. The results of this sensitivity analysis are discussed, and illustrate the potential benefit of carrying out sensitivity analysis in determining feasible and marketable product grades.CITATION:Everett, J E, 2015. Block model data reduction and sensitivity analysis, in Proceedings Iron Ore 2015, pp 263–270 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By R. M. Jara

This work evaluates and characterizes the impact of the support size and mining dilution of a block model in the operation and selection of equipment at an open pit mine. An exploratory analysis and geostatistical modelling of the grades assayed on a set of drill hole samples is performed, which allows constructing a grade model on a dense grid by means of a conditional simulation. The grades are then averaged to greater selective mining unit supports in order to proceed with the study and methodology. First, the metal-tonnage curves are used to analyse the loss of selectivity on the in situ resources caused by a change of support. Concerning the ore reserves and their mining sequence, defined in the pit optimization and analysis process, the same curves prove that the loss of selectivity is more accentuated. Second, the importance of the block boundary dilution produced during mining operations is assessed. Its value depends on the amount of ore in contact with waste, on the loading error of the equipment and on the ore loss/waste dilution criterion assumed by the planner. The dilution percentage and the differences between waste and ore grades become higher when the block size decreases. For these reasons, considering the dilution in the production plans makes mining a small support more constraining. An adequate delimitation of the orebody can improve the mining selectivity, leading to greater income. Finally, a study of the increase in mining cost that provides a zero difference in NPV between the different block size options is carried out, in order to determine the maximum increase in mining costs for which it remains profitable to mine at a smaller block size. Keywords: Mining selectivity, support effect, block boundary dilution, selective mining unit size, block model.

Jan 1, 2006

By G. Rong, W. Du

Stability of some potential unstable blocks in the left bank slope of Baihetan hydropower station is evaluated in this paper using the three-dimensional (3D) limit equilibrium method. The Baihetan hydropower station is in the downstream of Jinshajiang River, China. The geological condition in the river valley is complex, and many large discontinuities are detected in the slope of the two banks. As a result, much attention should be paid to the stability of the slope in the feasibility study stage. Because the left bank slope is an oblique consequent one, we mainly focus on the slope stability analysis in the left bank. Comprehensive geological exploration is conducted in the studied area and the detected discontinuities are well researched. By building a 3D geological model of the left bank slope, three potential unstable blocks which are close to the dam site are detected. An irregular wedge analysis method is then used to calculate safety factors of the three blocks under three conditions, which are natural condition, rainfall condition, and seismic condition, respectively. It is found that the safety factors of the block 1# and the block 2# are quite low when compared to the suggested values. Extra care must be exercised when excavating the slope near the block 1# and the block 2#. A preliminary reinforcement is also suggested.

Jan 1, 2015

By S. Fuentes, J. Cáceres

"During the past fifteen years, mines utilizing the block caving method have improved performance and systematically reduced total mining costs.This paper describes improvements in mine design, mine planning, and mine management, including methods enabling the Chilean and international mining industry to ensure cost savings and productivity growth while using the block caving method. These improvements have encouraged the re-evaluation of underground operations at operating and closed open pits, and challenge surface mining applications as the only low-cost mining method. This paper describes a strategy to estimate the optimum open pit to underground transition time during the life of a mine. IntroductionDuring the last fifteen years, block caving mines have experienced huge changes in designs, planning and administration. These changes have permitted operators to drastically reduce costs, improve equipment productivity, and improve overall business performance. As a consequence of this situation, the block/panel caving mining system is challenging actual open pit operations to maximize the net present value (NPV)."

Jan 1, 2004

By Ankit Jha, Javad Sattarvand, Aaron Young

Blockchains are one of the prominent disruptive technologies that are being implemented in several disciplines. The application of blockchains in the mining and mineral industry can provide utility for several processes especially when the industry is undertaking digital transformation. The governing principles of blockchain technology are applicable in undertaking transformation in several processes within the mining industry. This study investigates the applications of blockchain technology within the realms of the mining industry and identifies key areas of implementation. A systematic review of publications on academic platforms relating to blockchain technology in the mining industry did not retrieve a considerable number of articles. Consequently, a thorough review of white papers and articles authored by individuals on use cases within the mining industry is compiled and presented in this manuscript. This paper identifies all the potential areas within the mining industry where blockchains could provide value and improve processes through their implementation. The broad area of implementation of blockchains includes supply chain, traceability in spare parts, contract management, regulatory compliance, and cyber security.

Nov 23, 2023

By Ankit Jha, Javad Sattarvand, Aaron Young

Blockchain technology is one of the prominent disruptive technologies that are being implemented in several disciplines. The application of blockchains in the mining and mineral industry can provide utility to several processes especially when the industry is undertaking digital transformation. The governing principles of blockchain technology are applicable in undertaking transformation in several processes within the mining industry. This study investigates the applications of blockchain technology within the realms of the mining industry and identifies key areas of implementation. A systematic review of publications on academic platforms relating to blockchain technology in the mining industry did not retrieve a considerable number of articles. Consequently, a thorough review of white papers and articles authored by individuals on use cases within the mining industry is compiled and presented in this review article. This review article identifies all the potential areas within the mining industry where blockchains could provide value and improve processes through their implementation. The broad area of implementation of blockchains includes supply chain, traceability in spares parts, contract management, regulatory compliance and cybersecurity.

Mar 1, 2024

By A. Belleau, F. Lavoie

"Quebec Iron Ore Limited (QIO), a subsidiary of Champion Iron Limited (Champion), secured assets in early 2016 from the previous Bloom Lake operations in the heart of the Labrador Trough region of Northern Quebec, Canada. A plan was developed to bring the Bloom Lake facility back in operation once the iron ore market conditions improved. The project restart involved several aggressive moves to change operational effectiveness, one of which was the utilization of the existing Phase 1 Plant with an upgraded process flowsheet and equipment. The production target was 7.4 million tonnes per annum of 66% iron ore concentrate with an approximate 10% increase in iron ore recovery. The Phase 1 upgraded flowsheet was initially based on review of historical Phase 1 data and pilot testing data undertaken during the original Phase 1 operation and was finalized once additional metallurgical test work and process modeling was carried out by Mineral Technologies in late 2016. The final upgraded flowsheet is comprised of rougher spirals, rougher middling scavenging spirals, and an up-current classifier (UCC) with overflow scavenging spiral stage. A portion of the gravity circuit tailings treated by a series of wet high intensity magnetic separators (WHIMS) to boost overall iron recovery. This paper will describe the efforts taken to test and design the Bloom Lake Phase 1 upgraded flowsheet and report on the plant performance since commissioning in first quarter of 2018.SITE HISTORY The Bloom Lake iron mine property is located approximately 13 km north of Fermont, Quebec, and 10 km north of the Mont Wright iron ore mining complex, property of ArcelorMittal Mines Canada. The Bloom Lake mine facilities include a 32 km railway to efficiently transport the high-quality iron concentrate to a loading port located in Sept-Iles, Quebec. The Bloom Lake property was first explored in 1951 and went through multiple minor exploration campaigns by different companies up until 1998. A major exploration program was conducted by Quebec Cartier Mining (QCM) in 1998. This program included line cutting, surveying, diamond drilling, geological mapping, mini-bulk sampling, bench-scale preliminary metallurgical test work and preparation of a “mineral resource” estimate."

Jan 1, 2019

By E. von Maltitz

IN his highly interesting paper on "Piping and Segregation in Steel Ingots,"1 Prof. Howe emphasizes the effect of successive phases of internal pressure in the ingot in the evolution of gas, and the consequent formation of blow-holes. From his statements in other places, it may be inferred that he does not here intend to ignore the other variable factor, temperature, but rather to discuss this one more particularly. At all events, it is my purpose not to engage in controversy with Prof. Howe, but rather to contribute, towards the complete elucidation of this important subject which we all desire, my own views and experience. If, in doing so, I specially emphasize other factors than pressure, I need not be understood as denying what I do not think it necessary to discuss fully. Nor, in presenting my own original conclusions, need I be understood as claiming to be the first who ever reached or announced them. Many things are asserted or suggested upon inconclusive evidence; and to confirm such tentative propositions may be as valuable a service as to overthrow them. In the following passage, Prof. Howe adduces analogies, based upon the behavior of charcoal and of water, respectively, which seem to me questionable "In general, the. solvent power falls as the pressure falls ; and in general it rises as the temperature falls. Thus, to heat a solid, for instance charcoal, may expel part of its dissolved gas ; and a tumbler of water drawn cold from the faucet gradually evolves gas, as it stands and warms up on the sideboard." (p. 238.) Charcoal is a solid body, which has the property not only of absorbing gases in large quantities, but also of expelling the thus absorbed gases upon heating. A comparison between charcoal and iron as to the absorption of gases is scientifically not possible ; the gas-content of charcoal is partly due to the

Sep 1, 1907

By S Nowosad, A Binder, O Langefeld, M Bothe-Fiekert, F Apollo

The mining industry faces complex and urgent challenges driven by an increasing demand for raw materials, and a socially demanding globalised world. The extraction of primary raw materials is today more important than ever as one of the cornerstones towards a sustainable future since the increasing demand for the raw materials required for the energy transition. In the last three years, leading countries as USA, China, Canada, Australia, and the European Union (EU) have developed and adopted strategies to enhance domestic extraction capabilities, diversifying sources, fostering innovation in recycling, and promoting international collaboration related to critical raw materials. On 2022, the Inflation Reduction Act was signed into law in the USA, in June 2023, the Australian Critical Minerals Strategy 2023–2030 was published and in March 2024, the Council of the EU adopted the European Critical Raw Materials Act. On the other hand, raw materials extraction is facing higher environmental and safety standards and regulations, as well as scrutiny from the broader public. Regrettable environmental accidents as tailing dam failures or acid mine drainage occurrences have led to a general distrust of mining activities leaving mining companies with the dual imperative of increasing output while implementing sustainability, decarbonisation, and circularity as a core value in their production processes. This challenging environment offers the opportunity to enhance ‘blue mining’ (BM) as a sustainable holistic approach that integrates the principles needed to plan sustainable, reliable, and responsible mines for today’s and future generations by implementing the principles of circular economy (CE). This requires a fundamental shift from the traditional linear economy approach to a sustainable, circular economy strategy. At its essence, BM encapsulates four crucial aspects – energy, ergonomics, water, and circularity and integrates these four aspects into integrative mine planning, defining clear goals and objectives from the ‘blueprint’ of a mine towards a beneficial post-mining activity. Its implementation can lead to maximisation of resources beyond the life of the extractive mine and sustainable use of materials by integrating the principles of circular economy and multiuse mine, see Figure 1. These concepts complement and recognise the need to minimise environmental and social impacts while advancing economic development. Finally, this contribution explains the requirements and challenges of moving from linear to dynamic planning approaches under the BM concept. This way, BM stands as an approach that can contribute to the mining industry receiving necessary approvals and support from society leading to a long-term transformation of the industry’s image.

Sep 1, 2024

By Angela Binder, Mareike Schubert, Yichen Jiang, Sandra Nowosad, Oliver Langefeld

GermanyINTRODUCTIONThe mining industry is currently characterized by various factors such as environmental impact, resource scarcity, social responsibility and geopolitical uncertainty. The production of minerals required to meet the demand for renewable energy is expected to increase by 500 % by 2050, particularly for critical minerals such as graphite, lithium and cobalt 1. Easily accessible deposits are often depleted, meaning that deeper and more complex deposits need to be developed. Furthermore, investors’ value systems have shifted towards more sustainable practices. Alternative approaches to solving this problem are therefore currently being developed, such as the Modular Mining Systems concept for scalable and adaptable mining projects 2. Many mining companies have also taken important steps to become more sustainable, implementing measures such as proactive closure strategies, restoration programs and the development of renewable energy projects. In the European Union, laws such as the Critical Raw Materials Act and the Net Zero Industry Act support the mining industry 3,4. They see it as important for the energy transition and promote more sustainable ways of working in the industry Particularly negative environmental impacts such as land degradation, scarcity of local water resources, water pollution and greenhouse gas emissions are ingrained in society’s memory. Despite these efforts, the public image has not yet changed. To change this perception, the industry must strive to better communicate its sustainable practices and the steps it is taking towards a more responsible and sustainable future, promote transparency and build trust.Digitalization, automation and electrification are driving the digital transformation in mining. However, their implementation can lead to higher capital expenditure, limiting their adoption across the industry. Furthermore, implementing new technologies can be a daunting task for any organization. Change management comes into play when introducing such disruptive technologies. It involves preparing an organization for change, potential resistance and establishing effective communication. This helps to ensure that the implementation is successful and the benefits of the new technology are maximized. Digital transformation requires well-trained, young mining, electrical, mechatronic and software engineers with a deep understanding of information systems. Unfortunately, the industry faces the enormous challenge of attracting this younger generation, who have little interest in the extraction of raw materials. The need for action is compounded by an aging active workforce heading into retirement and the forecast of increasing demand for critical minerals.In this challenging environment, the concept of Blue Mining with its constant further developments represents a promising approach. This implies a shift from a linear to a sustainably oriented circular economy. For the mining industry, this specifically means the introduction of innovative technologies, the increased recovery of materials from waste and the consistent questioning and application of circular principles along the entire life cycle of a mine. Such a change can not only reduce the environmental impact, but also contribute to economic resilience and increased social acceptance of mining.

Feb 1, 2025

By Jeff Hopple

"Bluestone Dam in Hinton, W.Va., along the New River, is owned and operated by the U.S. Army Corps of Engineers (USACE). Completed in 1949, the dam is 165 ft (50 m) tall, 2,048 ft (624 m) wide, and encompasses a water shed that is 4,600 sq mi (11,914 sq km). The Bluestone Dam Safety Assurance (DSA) Program began in 2001, and is a multiple-phase construction project to upgrade the capacity and stability of the structure to meet the probable maximum flood event. Installing 216 high capacity rock anchors was a major feature of the work.The USACE selected Brayman Construction Corporation to perform Phase 2B of the construction modifications to the Bluestone Dam. Brayman was responsible for installing the high capacity rock anchors, which range in size from 3 to 61 strands and have a design load up to 2,145 kips (9,541 kN). Drill holes range in size from 6.5 to 15 in (16.5 to 38 cm), and required full length corrosion protection. Of the 216 anchors, 57 were installed on top of the dam to resist overturning and the remaining 159 were installed on the face of the dam at a 45-degree angle to resist sliding.To gain access to the face of the dam anchor locations, the project required dirt benches, excavations with temporary shoring, and steel platforms. To access anchors on the east and west abutment faces, the team excavated over 10,000 cu yds (7,645 cu m) of material. Support of these excavations included the design and installation of three soil nail walls with over 145 nails and 3,500 sq ft (325 sq m) of shotcrete. The project also called for a 780 ft (237 m) long steel platform to gain access to the spillway anchors. The Stratus Group designed the platform to support two 85 ton (80 tonne) crawler cranes and as many as five drill rigs that were the equivalent to a design load of 3.5 ton per sq ft (335 kN per sq m). Once the final platform design was approved, fabrication of roughly 3 million lbs (1,360 tonnes) of structural steel began. Brayman’s in-house fabrication shop, in conjunction with Dura-Bond Industries and Advantage Steel, collaborated to fabricate and install the platform in less than five months. Flexibility in the platform design allowed for sections of the platform to be lowered as much as 16 ft (4.9 m) to provide access to anchors at lower elevations along the spillway face. In addition to the main spillway platform, Stratus Group, Brayman, Dura-Bond and Advantage designed, fabricated and installed six other unique platforms to facilitate anchor construction on various areas of the dam."

Jan 1, 2014

By W. J. Maloney, H. E. Tuneblom, A. J. Smith

The development of a large regional water supply in Southern West Virginia faced several hurdles. This paper deals with the design and construction of the intake shaft where a combination of cutting edge mechanical excavation technologies were utilized to produce a world class project.

Jan 1, 1999

By A. Fischersworring-Bunk

The new inline six spark-ignition engine is the realization of BMW's concept of efficient dynamics at high technological level to achieve the attributes of low weight and high efficiency, The paper presents different aspects of the development and manufacturing of BMW's inline six-cylinder engine magnesium-aluminium composite crankcase, Reference will be made on the AJ magnesium alloy optimization approach to balance between mechanical properties and the high pressure die cast ability requirements, Next to this aspect some mechanical design issues will be covered, with CAE methods playing an instrumental role in the early project stage for the assessment of the compound concept, Due to the compound design chosen, the interface posed challenges to both design and productions, A set of novel techniques has been used to cope with these tasks.

Jan 1, 2006

Meeting of Feb. 16, 1915.-The Committee on Membership was appointed with the following personnel: John H. Janeway, Chairman; Karl Filers, Lewis W. Francis, Louis D. Huntoon, and Thomas H. Leggett. President Saunders announced the appointment of the Committee on Increase of Membership, as shown on p. xxviii of this Bulletin. The reproduction by the anastatic process of 100 copies of Volume IX of the Institute Transactions was authorized. The sum of $50 and the exchange of the Bulletin. was awarded to the commission publishing the Annual Table of Constants. The sum of $49.07 was contributed to the expense of the John Fritz Medal Board of Award for the year 1914, and the Institute agreed in the future to share the annual expense for the John Fritz Medal Board of Award not to exceed one-quarter of $500 in the year. Upon the recommendation of the Committee on Membership, 36 Members, 1 Associate, and 13 Juniors were elected. The resignations of 26 members were accepted. L. D. Ricketts was elected a Vice-President of the Institute to serve the unexpired term of W. L. Saunders. George D. Barron was elected a Director to serve the unexpired term of L. D. Ricketts.

Jan 4, 1915

Meeting, June 26, 1913).-On the petition of 29 members residing in and near San Francisco, Cal., the San Francisco Local Section was established. The territory of the St. Louis Local Section was established to include the following States and parts thereof: All the State of Missouri ; That part of the State of Illinois south of and including the city of Urbana ; That part of the State of Indiana south of and including the city of Indianapolis ; That. part of the State of Kentucky west of and including the city of Frankfort ; That part Of the State of Tennessee west of and including the city of Nashville That part of the State of Arkansas north of and including the city of Little Rock.

Jan 7, 1913