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By S. Akhtar

Interstitial compounds of iron, cobalt, and nickel, and their binary and ternary mixtures with silver, gold, palladium, and platinum were prepared and tested as fuel cell catalysts. The first step in the preparation of the interstitial compounds consisted of preparing finely divided metals. This was done either by the Raney method or by reduction of precipitated hydroxides of the metals. The finely divided reduced metals were then treated with carbon-and/or nitrogen-containing gases to prepare their carbides, nitrides, and nitrocarbides. The materials were tested for cathodic activity towards O2 and for anodic activity towards H2, C3H8, NH3, CO, and N2H4 in acid and alkaline electrolytes at 25° to 90° C in half-cell assemblies. Samples of carbided and nitrocarbided INi-lAg-1Au were about one fifth as active as Pt-black in the reduction of O2 in 35 percent KOH solution, whereas the activities of several interstitial preparations exceeded the activity of Pt-black in the reduction of O2 in 12M KOH containing N2H4. Nitrocarbides of x-Fe2C, 3Ni-1Au, and 1Ni-3Au were effective catalysts for oxidizing N2H4 in liquid NH3 containing NH4SCN. Corrosion of the catalysts by electrolytes was severe in many cases.

Jan 1, 1970

By Frank E. Cash

The Bureau of Mines in its safety work has for a number of years advocated and recommended the use of permissible portable electric cap lamps for use in all mines. In the course of time required for the evolution from an unsatisfactory to an efficient and safe light, but encouraging increase in their use has been experienced in Alabama. As early as 1916, small installations of these safer lamps were made or an experimental basis by several operating companies, and the first complete mine installation eras made at the Virginia mine of the Gulf States Steel Co., July 1, 1918. From the experiments in 1316 and the complete equipment of the first mine in 1918 gradual progress has been made until there are now 30 installations with 10 operating companies; as a result 20 mines have been put entirely and 5 partly on, closed lights, and 3 companies equip their engineering departments; two installations of closed lights are maintained by other companies for emergency use. One of the mines partly on the electric cap lamp is an ore mine - the only one in Alabama (and one of the very few in the United States) that uses closed lights. ACKNOWLEDGEMENTS The full cooperation of operating officials, lapmen, and lamp representatives was given in the collection of the data in this report, and is hereby acknowledged.

Jan 1, 1928

By P C. Miclea

Transportation networks extend every day around the world, requiring safe and well-maintained structures for efficiency and for users’ safety. Due to specific features of the infrastructure, such as longer tunnels, increased traffic and marginal safety rules, fire safety in rail and road tunnels becomes more challenging.The situation becomes more critical due to the global economy and increasing worldwide tourism, with multi-national companies often involved in both design and construction of transportation routes or systems in other countries. Tourism brings the risk of visitors becoming victims in a foreign land; thus, international law becomes more and more applicable to transportation projects all over the world, requiring a consistent approach to safety (UN Economic and Social Council, 2001; US DOT Federal Highway Administration (FHWA) 2006; US Transportation Research Board, Committee on the Role of Public Transportation in Emergency Evacuation, 2008; UK Parliamentary Office of Science and Technology, 1997).There are significant differences between rail and road tunnels, both in their functionality and safety requirements. Most tunnels over a certain length are equipped with emergency ventilation systems capable to control the spread of smoke by creating an air stream in the desired direction. Besides ventilation, fire-life safety (FLS) includes smoke and heat detection by linear or spot detectors, closed-circuit television (CCTV) and public address systems with prerecorded announcements, as well as evacuation signage and monitoring capabilities (Vägverket – Swedish National Road Administration, 2004).There isn’t a consistent, worldwide approach to the design of emergency ventilation systems for tunnels, with significant differences from continent to continent (US DOT Federal Highway Administration (FHWA), 2004, US Federal Transit Administration, Transportation Research Board, 2006). In North America US NFPA 130 and 502 standards for rail and road tunnels, respectively, represent the main criteria, however, they are continually revised and new versions issued every three years. For road tunnels the World Road Association PIARC issues guidelines, but they are not truly enforceable. There are no similar international guidelines for rail tunnels, except general recommendations by the International Association of Public Transport (UITP) (IAPT, 2003).In Europe the Directive #54/EC adopted by European Community Parliament in 2004 requires a minimum level of safety for road tunnels users in all existing and proposed tunnels in the Trans-European road network that are greater than 500 m in length. Authorities having jurisdiction in many other individual countries, such as Australia, Austria, Germany, Japan and others, enforce specific safety regulations (Miclea et al, 2007). While it is impossible to summarise all aspects of this topic in a short paper, a review of the design approach, the existing differences in safety requirements, as well as applicable design solutions to meet safety codes for both rail and road tunnels are discussed below.

Mar 8, 2011

By AIME AIME

GENERAL COMMITTEES. SAN FRANCISCO:-ExECUTIVE, Hon. William C. Ralston, Chairman; RECEPTION, Prow. Samuel B. Christy, Chairman; SESSIONS, Frederic W. Bradley, Chairman; PRESS, H. Foster Bain, Chairman; FINANCE, Mark L. Requa, Chairman; EXCURSIONS AND ENTERTAINMENTS, Edward H. Benjamin, Chairman. Assisted by Harry P. Stow, C. W.Merrill, F. W. Griffin, Gelasio Caetani, Albert Burch, Newton Cleaveland, Corey C. Brayton and R. E. Cranston. Los ANGELES :-EXECUTIVE, Theo. B. Comstock, Chairman; R. W. Hadden, Secretary; H. R. Simpson, Treasurer. Institute Headquarters at Hotel St. Francis. The first and opening session, held Tuesday afternoon, Oct. 10,. in the Reception-Hall of the St. Francis, was called to order by State Senator William C. Ralston, Chairman of the Executive Committee, who in a few well-chosen words welcomed the visiting members and guests of the Institute to San Francisco. He said it was twelve years since the last meeting on the Pacific Coast and that it was here that the greatest feats. of mining had been accomplished in the history of the country. He told of the work that had been done on the continent and of the new methods introduced by the mining engineers for the betterment of the nation. He then introduced Capt. Robert W. Hunt, twice past President of the Institute, and present Acting President for the San Francisco meeting and the subsequent visit to Japan, who responded cordially to Mr. Ralston's welcoming address. By unanimous vote, the Secretary was instructed to send a telegram to President Charles Kirchhoff expressing regret for his absence, and hoping for a rapid improvement in the health of his mother. The following papers were presented in brief oral abstract by the authors: . * Electrolytic Refining at the U. S. Mint, San Francisco, Cal., by Edward B. Durham, San Francisco, Cal. The Parral Tank System of Agitating Slime-Pulp, by Bernard MacDonald, Guanajuato, Mexico. * The Newport Iron-Mine, Ironwood, Mich., by B. W. Vallat, Ironwood, Mich. (illustrated by lantern-slides). * Distributed in pamphlet worm.

Nov 1, 1911

By R. A. Cattell

Progress of Bureau of Mines research related to oil and gas during the past fiscal year has been marked by the publication of more than 40 reports on the various phases of the work . These include papers dealing with the production of oil and gas , transportation of gas , chemistry and refining of petroleum , thermodynamic properties of hydrocarbons , and the processing and utiliza- tion of helium . As an additional service to Pennsylvania oil operators , a new suboffice was opened in Bradford , Pa . , during the year . With this addition , the work of the Petroleum and Natural Gas Branch of the Bureau of Mines is now conducted in two large stations , the Petroleum Experiment Station , Bartlesville , Okla . , and the Petroleum and Oil Shale Experiment Station , Laramie , Wyo . , and three field offices and laboratories at San Francisco , Calif . , Dallas , Tex . , and Franklin, Pa., and two suboffices, Wichita Falls, Tex., and the newly opened suboffice at Bradford, Pa. In addition, this Branch operates large-scale helium-production plants in Texas, Kansas, and New Mexico, and maintains ex- tensive helium-bearing gas reserves in Texas and New Mexico. All helium opera- tions are supervised from headquarters at Amarillo, Tex. A small headquarters staff is in Washington, D. C. A backward glance at the road traveled during the past several years by the Petroleum and Natural Gas Eranch of the Bureau of Mines brings out a general background for the events of the fiscal year 1949. Throughout the fiscal year 1945, the activities of the Branch were still mainly concerned with such war activities as making special field studies for the Petroleum Adminis- tration for War, finding ways of increasing rates of production, and supplying data pertaining to the manufacture of aviation and jet-propulsion fuels. A period of adjustment came in 1946, characterized by a turning from war to peace procedures and efforts to give wide distribution to technical facts ob tained in wartime research; also, there came a realization that the demands of war had broadened the horizons of research. This was emphasized in 1947, when a peacetime program was restored, based upon the long view of the Bureau's place as a research agency in oil and gas. Close attention was given to tech- nical detail in 1948, and emphasis was placed on maintaining a balance between the industrial need for technical knowledge and Governmental-research possi- bilities in the fields of (1) withdrawal of petroleum from natural deposits, (2) utilization of petroleum and its products, and (3) commercial utilization of helium. Studies of petroleum production and utilization and helium production and utilization are the normal functions of the Branch. These functions (sometimes expressed in different words) have been the mainstay of this organization since initiation of the work. The details of approach vary with changing conditions, but, fundamentally, the functions have been the same in both peace and war. The work of the past fiscal year has emphasized the advantages that accrue when Government and industry join in a wise use of technical and scientific knowledge gained through research. Outstanding evidence of the beneficial results of cooperative effort by the Bureau of Mines and various organizations is found in the following typical examples, the details of which are discussed in the body of this report. Working in close cooperation with operators along the Gulf Coast, the Natural Gasoline Association of America, and the National Association of Cor- rosion Engineers, the Bureau found, through field testing, that corrosion protection by means of chromates in high-pressure gas-condensate wells costs less than $1 per million cubic feet of gas produced. Laboratory experiments to measure the corrosion effects of carbonic and propionic acids on various steels and alloy steels gave data that will serve as guides in the selection of new. materials for the construction of well equipment to be tested by industry under actual service conditions.

Feb 1, 1950

By R. S. Douglas

THE Granby Consolidated Mining, Smelting and Power Company, Limited, is engaged in the mining and concentrating of copper ores, and, incidentally, in the mining of coal and the production of electric power. The Company has been engaged in these various operations both on the mainland of British Columbia and on Vancouver island for the past forty-five years. This paper will attempt to cover their present operations in the Similkameen mining district of southern interior British Columbia. GENERAL CHARACTER OF THE DISTRICT The Interior Plateau in southern British Columbia ranges in elevation from 3,000 feet to 6,000 feet. In the vicinity of Princet0n, a depression in the Plateau forms a well defined basin which is floored with a series of nearly flat-lying Tertiary sediments containing some workable seams of lignite. From this basin, the upland surface rises gradually t0ward the south, from an elevation of 2,000 feet at Princet0n to 4,000 feet at Copper mountain, and 6,000 feet in the upper parts of the Similkameen basin, where it merges into the rugged and diversified t0pography of the Cascade system, with glacier inhabited peaks rising to over 9,000 feet. The valleys of Similkameen river and its tributaries are wide, having flaring sides and gentle slopes, and are separated one from another by subdued rounded spurs, of which Copper mountain is typical. The drainage of this district is taken care of by Similkameen river and its larger tributaries, such as Pasayten river, and Wolfe, Friday, and Whipsaw creeks. The name Copper mountain is applied to a gently arched, nearly flat-topped spur between the deep valley of Similkameen river to the west and the shallower valley of Wolfe creek tO the east. The mountain is appro-priately named from the number of copper deposits occurring on its sides and summit, some of which have been developed int0 an important producer, known as the Copper Mountain mine.

Jan 1, 1943

By Ronald Erdmann

Today the BOF filter dusts and sludges are mainly dumped due to their zinc contents. By typically ranging from 2 to 5 % they prevent the filter dusts and sludges from beeing recycled via the blast furnace route. Based on the different discharge kinetics of Iron and zinc during the main blowing period In a bottom stirred BOF a simple and efficient system for recovery allow zinc fractions has been developed. The obtained material Is suitable for recycling without nsc of shell formation In the blast furnace. Different subsequent development steps have been performed. By starling with a very simple lime dependent model the sludge from the BOF off gas cleaning system was collected in two different sludge channel systems. This model based an the fact that most of the scrap based zinc Is discharged from the melt within the first eight to ten minutes of the BOF process. To Improve the system a spectroscope zinc sensor was Installed at the hot section of the off gas cleaning system to get more reliable informations on the actual zinc concentation of the BOF dust. By use of the system up to 50 % of the BOF sludge can be recycled.

Jan 1, 1995

By J. H. Welsh

This Bureau of Mines report presents guidelines to be considered in the design, installation, and operation of environmental mine monitoring systems in underground coal mines so as to enhance safety in the U.S. mining industry. A review of the current status of mine monitoring in the United States is also provided.

Jan 1, 1987

[RALPH ADAIR Ore Dressing Consultant Bull Mtn. Rd., Asheville, N. C. Phone 4-1693 JAMES A. BARR Consulting Engineer Mt. Pleasant, Tennessee Washington, D.C. BEHRE DOLBEAR & COMPANY Consulting Mining Engineers and Geologists It Broadway New York 4, N. Y. I. R. BERENT Engineering Consultants and Contractors Mineral Exploration, Mine Evaluation, Mine Designs and Mine Management 156, Ataturk Bulvari-Ankara, Turkey BLANDFORD C. BURGESS Registered Professional Engineer Mining Consultant Monticello, Georgia GLENVILLE A. COLLINS Mining Engineer Uranium examinations Cable "Coins" 8 Howard-Canfleld Bldg. Santa Barbara, Calif. COWIN & CO. Mining Engineers and Contractors Consulting Shaft & Slope Sinking Appraisal Mine Development Reports Mine Plant Construction I-lath St. S. W. B'ham, Ala., Phone 56-5566 MILTON H. FIES Consulting Engineer Rooms 1201-2. Albama Power Co. Bldg. Birmingham, Alabama]

Jan 1, 1952

By Maurice E. Bailey

The purpose of this study is to determine worker acceptance of modified mine equipment at various intervals during a twelve month period. A survey instrument was administered to the workers by two experienced miners in four interviews. All four interviews showed a significant positive response to all modifications, except the small size of the cab of the shuttle car; however, the small size produced significant negative responses with respect to comfort in each of the four interviews. Initially, (interviews one and two), there were significant negative responses with respect to manufacturer receptivity to operator suggestions and program management follow-through on operator suggestions; however, the third and fourth interviews showed no significant negative responses with respect to these items. Likewise, there were significant neutral responses in the first two interviews; however, the third and fourth interviews showed no significant neutral responses with respect to these items.

Jan 1, 1975

By Wilbert J. Huff

The work of the Explosives Division, Bureau of Mines, United States Department of the Interior, for the fiscal year ended June 30, 1939, is described in the following pages. This paper is the fourth of a series of annual reports covering the activities of the division since July 1, 1936. The studies outlined in this and preceding reports of the series have been conducted under the direction of the author and the respective unit leaders to whom specific credit is indicated.

Jan 1, 1940

By R. W. Watson

At the request of the Mine Safety and Health Administration (MSHA) the Bureau of Mines evaluated the potential hazards of three compressed oxygen self-contained self-rescuers (SCSR's) designed for use in under-ground coal mines. The evaluation followed the lines used in a similar investigation of chemical self-rescuers and involved laboratory experiments as well as field trials designed to simulate a mining environment. They included bullet impact, bonfire, feeder-breaker impact and feed-through, and mining machine runover tests. The work showed that the units were not inherently unsafe but that under certain conditions of extreme abuse they can present a potential ignition or explosion hazard. This, coupled with a survey of reported damage on SCSR's currently deployed in underground mines, which indicated a relatively high frequency of incidents leading to the destruc-tion of the units, led to new recommendations on the deployment of SCSR's. The recommendations formulated by MSHA state that the units should be either properly worn by the miner, stored in heavy containers, or otherwise protected from situations in which they might be accidentally ruptured or destroyed, such as runover by mobile mining equipment.

Jan 1, 1984

By Dexter C. Hatch

At MacIntyre Development of the National Lead Company, Taha s, New York,, the flotation plant was set up to recover ilmenite from the finer size fraction of the ore that cannot be efficiently treated in the main gravity-magnetic separa¬tion process. It was later expanded to handle the reground middlings from the tables wetherill magnetic separators. The ilmenite-magnetite ore is ground to minus 20 mesh in five 6 x 12 ft. rod mills in closed circuit with DSM screens. The minus 20 mesh screen undersize is pumped to four parallel sections each consisting of two rougher wet-magnetic separators and one cleaner separator for magnatite removal. The screen undersize from the fifth section is distributed to all four sections. The magnetite removed in the roughers is pumped back to the cleaners and the cleaner magnetite is dewatered in rake classifiers and carried by belt to the winter plant or the stockpile area. The nonmagnetic sands from rougher and cleaner magnetic separator are sized for table feed in eight pocket hydraulic sizers. The slime overflows from the Crocketts, the sizers, and the magnetite rakes are collected and pumped to three-inch cyclones for thickening and desliming. The cyclone underflow is the principal flotation plant feed.

Jan 1, 1962

By Dunbar D. Scott

The development in the perfection of mine-surveying instruments has been by no means rapid, as it has depended somewhat on the details of construction borrowed from astronomical and geodetic theodolites, largely on the restrictions laid down by mining companies and the prejudices of mine managers themselves, but more than all on the methods used in conducting surveys and the importance attached thereto. Mine-surveying, in some form or other, has been practiced from the very earliest times; but it has never kept pace with the other branches of surveying, or even with the art of mining itself, and cannot be recognized as an exact science until shortly before the beginning of this century. The works of Hero of Alexandria, who lived in the second century B.C., are still extant, and contain descriptions of a rectangular sighting-instrument, which he invented and called a diopter. His improvement upon this simple construction, which possibly he devised for use in the Greek mines for rough leveling-purposes and for laying out any angle, must be considered, says Hübner," as the origin of the highly perfected theodolite of to-day. Whether this instrument came into general use during the first centuries of the Christian era, is not recorded; in fact, no writer undertakes to tell how mine-surveying was conducted until 1556, in which year Agricola expounds the principles of mining and metallurgy in his De Re Metallica, devoting the entire fifth chapter to the practice of mine-surveying (see Fig. 1). In mediæval times those who possessed any knowledge of engineering skill made strenuous effort to keep their art a secret, partly on account of the miners' proverbial conservatism and partly for their own personal aggrandizement, and were, in

Jan 1, 1899

By DR. SAMUEL B. CHRISTY

? THE man is always greater than his work.? The training of the men who are to develop the mineral resources of the world is the most important problem connected with mining engineering. It becomes ever more important to civilization as the mineral wealth of the earth approaches exhaustion. I have therefore decided to consider a few of the more important problems arising in the training of the mining engineer, and especially those arising in America. THE PECULIAR NATURE OF MINERAL WEALTH. Mining and Agriculture are the two fundamental arts. Without the latter our existence would be precarious; without the former, our civilization impossible. Agriculture furnishes that regular supply of food and raiment which leads to the growth of large communities in which cultivated leisure first becomes possible; while raining furnishes the metallic thread from which is woven that complex fabric we call civilization. But in these two arts the conditions for success are widely different. Most of the crops that the farmer reaps may be harvested year after year, and the proper fertilizers being added, he may continue the annual harvest indefinitely, while, as a result of cultivation, his farm becomes yearly more valuable. But the crop the miner reaps can be harvested but once in the history of the race. Our mineral wealth has taken unknown ages to mature in the bosom of the earth. The ripened fruit can be plucked but once. There are no fertilizers for worked out mines. It never pays to work over a mine that has been

Sep 1, 1905

The growth and influence of Sherritt Gordon Mines Ltd. in the nickel producing industry has been quite phenomenal. Although the company's Lynn Lake deposit in Manitoba was actually dis- covered in 1941, it was not until 1945, when men and materials were more readily available as a result of the end of World War II, that the area was staked and news of the discovery leaked out. As a result of the discovery, Professor Frank Forward of the University of British Columbia was commissioned by Eldon Brown, then President and Man- aging Director of Sherritt, to develop a new nickel refining process. A pilot plant, based on the results of Professor Forward's research, was constructed in Ottawa, and after the successful testing of the Lynn Lake ore, Chemical Construction Co. was given a con- tract in 1952 for construction of a producing plant. By 1954, the Fort Saskatchewan refinery was operating at an annual production of 15 million lb of nickel metal in the form of briquetts or powder. Capacity has since been increased to 30 million lb.

Jan 10, 1968

By Ralph D. Parker

THE subject matter of this paper will be primarily restricted to the metallic mineral industry, which last year was responsible for almost 60 per •Cent of the total value of Canada's mineral production. It has been written that, in the broad sweep of eternal time, sixty years is as transient as a flicker of lightning in a summer night's sky. In the history of mankind and human endeavour, however, six decades can encompass momentous events and far-reaching •circumstances, all of which affect the lives of men and change the destiny of nations. This observation is con-firmed very positively by a study of our Canadian mining history, from either the broad viewpoint of human progress or the more specialized viewpoint of national economy. The past sixty years have witnessed vast changes in the economic importance of mining in this country's affairs, and also in the technology of the industry. Mining has emerged from the days of rule-of-thumb practice and is now taking on the stature of a highly diversified science.

Jan 1, 1962

By R. R. Sayers

A series of coal- mine catastrophes in the latter part of the first decade of this century focused public attention on the need for safety in mines and resulted in the establishment of the Federal Bureau of Mines , whose primary function was to promote safety and improve hygienic conditions of workers in the mineral and related industries . These activities are carried out by the Safety Division of the Bureau's Health and Safety Service . In general , the work performed by the Safety Division personnel may be classified as educational and investigative . Instruction is given in accident prevention for mine officials and miners ; first aid to the injured ; the use and care of oxygen breathing apparatus ; and advanced mine rescue and recovery operations . A specialized safety course is offered to the petroleum and gas industries . Division personnel also aids in or directs rescue and recovery work after mine fires and explosions ; assists at first - aid and mine rescue contests ; conducts safety exhibits and demonstrations ; and presents safety talks , often accompanied by sound safety motion pictures or latern slides , before employee and official groups , at meetings of Holmes safety chapters , at mining institutes , and at other safety or technical gatherings . Coal - mine fires and explosions are investigated , as well as quarry or metalmine explosions and fires , miscellaneous accidents , health and safety hazards , and safety conditions at mines and plants ; safety devices are investigated and developed . Field studies cover ventilation , methods of allaying suspended coal - dust particles , prevention of dust accumulations , the proper use of rock dust to prevent or limit explosions , explosives practices , and the care and use of underground equipment . The results of these studies and investigations are widely applied in the various training courses and are prepared as reports and recommendations , which are submitted to interested persons or are combined and distributed to the public as bulletins , technical papers , miners ' circulars , information circulars , and reports of investigations . These studies also afford a basis for the development of new or modification of old Safety Decisions of the Mine Safety Board of the Bureau of Mines . The following pages review the accomplishments of the division as regards safety during 1942,2/ with like information for a series of recent years and summaries to date . A striking feature of the division's work has been the safety education of more than 1-1/2 million persons who have taken first -aid and mine rescue training courses . That these efforts over a period of 3 decades have been successful is revealed by the decline in coal - mine fatality rates and a somewhat smaller decrease in metal - mining and quarrying fatality rates .

Apr 1, 1943

By Earl T. Hayes

THIS BIBLIOGRAPHY has been assembled to aid research by the Bureau of Mines, and others on high-purity tungsten. It appears approximately 50 years after the development of ductile tungsten-one of the first metals to be produced in a high-purity form. Requirements of the missile age are ever more demanding that engines rout hotter and space vehicles fly higher and faster. Thus, it has become necessary to reexamine all conventional materials of construction as well as to investigate new combinations. At this stage of our technology we have alloys capable of operation at 1,800° F. and several possibilities of developing some. that will be satisfactory up to 2,500° F. Strength-weight comparisons, detrimental to tungsten at, lower temperatures, disappear at this point, mid tungsten or its alloys appear to be the only metal capable of operation at truly high temperatures. The aim of this bibliography has been to include only references that concern improving the purity of tungsten-from processing the ore to treating the finished metal. In this sense it is a selected and not a critical bibliography. The period front January 1911 through February 1959 has been covered. Because repent literature has the greatest, value, most of the selected items refer to publications issued within the pest 5 years.

Jan 1, 1960

By John P. McDonnell

Cable supports offer several advantages over traditional secondary support methods by enhancing stress redistribution to pillars and gob areas, minimizing or eliminating timbers and cribs that reduce ventilation, eradicating material-handling injuries related to placement of crib supports, and providing a cost-effective alternative to secondary support. The U.S. Bureau of Mines, in researching alternatives to traditional roof support methods, designed and installed high-strength cable supports to improve the stability of longwall gate road and bleeder entries in a Western U.S. coal mine. With the cooperation of industry, methods were developed to install cable supports in a tailgate and bleeder entry test area using traditional resin cartridges. Resin-grouted cable bolts were also installed and evaluated in additional longwall gate road and bleeder entry systems at the study mine. The cable-bolted areas successfully maintained roof support throughout the tailgate and bleeder entries. Cable supports replaced wood cribbing as secondary support in the bleeder entry system and minimized the use of cribbing in the longwall tailgate entries. This report describes the theory, application, and advantages of cable supports and presents mine measurements made to assess the cable performance during the retreat process of longwall mining.

Jan 1, 2010