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By Yuting Xue, Alper Kirmaci, Taghi Sherizadeh, Khaled Mohamed

Resin-grouted bolts serve as a crucial means of stabilizing yielded coal ribs in underground coal mines. A comprehensive investigation into their efficacy was undertaken by a collaborative effort between the National Institute for Occupational Safety and Health (NIOSH) and Missouri University of Science and Technology (MST). This study involved pull-out tests in multiple locations, including six coal mines and the NIOSH research mine. A total of seventy-three (73) tests were conducted, of wide range of anchorage lengths, ranging from a short encapsulation length of 0.305 m to a fully grouted encapsulation length of 1.524 m. The test findings indicate that when short encapsulation bolts are installed at high rotation speeds, their anchorage capacity is significantly reduced, leading to failure at the bolt-grout interface. Conversely, when these bolts are installed at lower rotation speeds, they exhibit greater capacity, with failure occurring at a higher anchorage load equivalent to the yield load of steel rebar. No matter what the rotational speeds were used during bolt installation in this study, the fully grouted bolts consistently experienced failure at the ultimate load of the steel rebar. Most of the tests carried out on partially grouted bolts with anchorage lengths of 0.610 - 0.914 m have shown behavior patterns like the fully grouted bolts, although exhibiting reduced stiffness. The outcomes of this research offer a profound insight into the ways in which resin-grouted bolts enhance the stability of coal mine ribs.

Feb 1, 2024

By D. B. Taliaferro

An accurate knowledge of the water content of oil-bearing sands4/ now is recognized as an important factor in calculations of the flow of oil through the sands to producing wells and in the estimation of oil reserves. To this end the Bureau of Mines laboratories are using a method that is an adaptation of the A. S. T. M. method of determining the water content of petroleum products (1).5/ However, the apparatus and technique have been altered slightly, as described in this report, to increase the precision of the method without affecting the simplicity of procedure or speed with which determinations may be made. Until recently petroleum engineers, when estimating reserves assumed that the entire pore volume of the oil-saturated parts of producing sands was filled with oil, as it was generally thought that the oil, water, and gas in any formation had separated completely during geologic time into distinct layers because of their difference in density. In 1929 Lindthrop and Nickolaeff (12) reported experimental results from which they concluded that 22 to 30 percent of the pore volume of producing sands in the Grozay district, Russia, was filled with water when the fields were discovered. Since that time numerous investigators (5, 7, 8, 10) have found evidence of water in the sands of now oil-producing fields and old fields that never produced water with the oil.

Jan 1, 1940

By D. B. Taliaferro

An accurate knowledge of the water content of oil-bearing sands4/ now is recognized as an important factor in calculations of the flow of oil through the sands to producing wells and in the estimation of oil reserves, To this end the Bureau of Mines laboratories are using a method that is an adaptation of the A. S. T. M. method of determining the water content of petroleum products (1).5/ However, the apparatus and technique have been altered slightly, as described in this report, to increase the precision of the method without affecting the simplicity of procedure or speed with which determinations may be made. Until recently petroleum engineers, when estimating reserves assumed that the entire pore volume of the oil-saturated parts of producing sands was filled with oil, as it was generally thought that the oil, water, and gas in any formation had separated completely during geologic time into distinct layers because of their difference in density. In 1929 Lindthrop and Nickolaeff (12) reported experimental results from which they concluded that 22 to 30 percent of the pore volume of producing sands in the Grozay district, Russia, was filled with water when the fields were discovered. Since that time numerous investigators (5, 7, 8, 10) have found evidence of water in the sands of now oil-producing fields and old fields that never produced water with the oil.

Jan 1, 1940

By Vernon C. Allison

The explosibility of coal dust has long been recognized by competent investigators as constituting one of the dangers of mining coal and in the use of pulverized coal as a fuel in industrial plants. The Bureau of Mines has carried on extensive series of experiments dealing with this subject, and has not only developed methods for the practical prevention of this danger, but in the, course of these experiments has developed a standard method of determining the relative explosibility of coal dusts and other organic dusts.3 Oil shale contains compounds 'of carbon and hydrogen that are either of a petroleum nature and are strongly ,adsorbed upon the incombustible part of the shale, or else are present in the shale as a compound ("kerogen") which has the property of changing into petroleum-like products when acted upon by heat. The oil shales may contain varying amounts of the organic matter, ranging from a trace to more than 66 per cent, depending upon their richness; therefore, it is important to know whether the dusts formed in mining and handling these oil shales are explosive when mixed with air and if so, to indicate remedial measures. This paper gives the results of explosibility tests of several pulverized oil shale's, selected as being typical of those which in the future may be used in commercial shale-oil production test on a sample of typical Colorado oil shale has been., published in an earlier paper.4

Jan 1, 1926

By V. Baltazar

The behaviour of arsenic and antimony during copper electrorefining was studied in order to identify the conditions under which good quality copper cathodes could be produced from anodes with high levels of these impurities. Examination of the effect of current density over the range 21 to 37 mA/cm2 indicated that the relative amounts of As and Sb entering the electrolyte affected the onset of passivation. When the ratio of As/Sb entering the electrolyte was greater than 2, the anodes showed no sign of passivation even at the highest current density; when the ratio was less than 2, the anodes passivated at 37 mA/cm2. Cathode analyses showed that anodes with an As/Sb dissolution ratio less than 2.0 tend to produce cathodes of inferior quality even at normal current densities (25.7 mA/cm2). The criterion of a minimum As/Sb dissolution ratio of 2.0, and mathematical correlations for the distribution of As and Sb between the electrolyte and slime developed in a previous study, allow the calculation of the maximum allowable Sb level in en anode for a given As concentration. Analyses of plant data at the CCR Division of Noranda Inc. for the last four years of operation have demonstrated that the use of this as a quality control tool has allowed the quality of copper cathodes to be maintained despite a significant increase in the average Sb levels in anode receipts.

Jan 1, 1987

By Walter G. Dupree

When the original version of this study was published in 1972 it was evident that a problem was developing on the energy scene. The ability of the United States to find the energy supplies it needed within its own boundaries--at least in the forms desired--was declining. Production of crude oil in the United States had peaked in 1970 and was declining slowly; environmental restrictions had begun to hamper the production and consumption of high sulfur coal; natural gas reserves were beginning to dwindle; and the development of nuclear power was proceeding more slowly than originally planned. Shortfalls in energy supply were being met through the importation of increasingly larger quantities of petroleum, but supplies were adequate and the price of the imports was below that of domestic production. The energy problem was more prospective than current. In October of 1973 the prospective problem became the "Energy Crisis' when the Arab petroleum exporting countries reduced crude oil production, imposed an embargo on the shipment of crude oil to the United States, and then raised the price of crude oil in a series of large steps. This crisis was a clear demonstration of the dangers of the dependence of the United States on imported petroleum, and of the Nation's vulnerability to the actions of the oil exporting countries. After the embargo was lifted, attention shifted to the immediate hardships resulting from the higher prices for gasoline, fuel, and electricity,

Jan 1, 1975

By Majorkiewicz A

Engineering of gold treatment facilities complete with infrastruc- ture in a remote location such as Papua NewòGuinea present unique problems to the design team. Site location, topography, ground conditions and infrastructure are some of the major hurdles to overcome when setting out on the design of such plants. This paper discusses two such plants, located in two distinctly different areas of Papua New Guinea and the solutions evolved in order to design successful operating facilities.

Jan 1, 1991

Mr. Address Member ,is hereby proposed by the undersigned; as a Associate Junior Member of the American Institute of Mining Engineers. Signatures of three Members or Associates. Place of birth Year of birth Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates Please give record of experience on following page with dates; for example, in the form used by "Who's Who In America" and similar publications.

Jan 5, 1917

By R. C. Troxell, S. C. Sun

EFFORTS to obtain definite quantitative data when employing the currently used bubble pick-up method', as a pre-flotation investigation tool led to the adoption of the magnifying mirror method and the microscopic method modifications. Quantitative data obtained by these two methods were converted into bubble pick-up indices and bubble pick-up coefficients. Rough correlations were established between the calculated indices and the results of contact angle testing as well as actual flotation under the same conditions.

Jan 7, 1953

By Ralph King

Blasting has been completed when the lawyer calls to say that a landowner has filed a suit alleging damages to the roof of his home. Mitigation talks fail to produce an adequate resolution and the case goes to court. The blaster has pictures of the area made after the blasting was done showing the good condition of the roof. However the judge fails to allow the photographs to be entered as evidence and the homeowner wins the case.

Jan 1, 2008

By J. C. Steinhobel

Answers to questions raised at the Symposium on Trackless Mining in Metal Mines Questions by J. O. Steinhobel (1) When rubber-tyred equipment is used for the delivery of stores and items of equipment, how is heavy material-pipes, rails, timber support, ventilation columns, etc.-dealt with? Termination of Membership In accordance with By-Law 7.6.1. of the Constitution of the Institute, the names of the undermentioned members have been removed from the membership register.

Jan 9, 1973

By Richard L. Ash, Calvin J. Konya

Proper selection of the spacing distance between blastholes is fundamental to successful blasting. Its value directly affects the profitability of an operation. It also exercises control over adverse effects such as airblast, flyrock, generation of ground vibrations, and overbreak. One of the more significant factors influencing the spacing's specific value is the initiation firing time intervals used between blastholes. Examples are described to illustrate some of the problems that result when spacing and timing are not compatible.

Jan 1, 1979

Mr. Address Member is hereby proposed by the undersigned, as a Associate Junior Member of the American Institute of Mining Engineers. Signatures of three Members or Associates. Place of birth Year of-birth Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates Please give record of experience on following page with dates; for e. ample, in the form used by "Who's Who In America" and similar publications.

Jan 6, 1917

Mr. Address Member is hereby proposed by the undersigned, as a Associate Junior Member of the American Institute of Mining Engineers. Signatures of three Members or Associates. Place of birth Year of birth Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates Please give record of experience on following page with dates; for example, in the form used by "Who's Who In America" and similar publications.

Jan 11, 1917

Mr. Address Member is hereby proposed by the undersigned, as a Associate Junior Member of the American Institute of Mining Engineers. Signature of three Members or Associates (not Junior Members). Place of birth Year of birth Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates Please give record of experience on following page with dates; for example, in the form used by "Who's Who In America" and similar publications.

Jan 1, 1918

Mr. Address Member is hereby proposed by the undersigned, as a Associate Junior Member of the American Institute of Mining Engineers. Signature of three Members. or Associates (not Junior Members). Place of birth Year of birth . Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates Please give record of experience on following page with dates; for example, in the form used by ?Who's Who In America" and similar publications.

Jan 3, 1918

Minerals are of course important to our way of living and hence the search and exploitation of minerals has always had a high priority in Australia. Metal mining commenced in South Australian in the 1840s when silver-lead and copper were first mined. This was Australia's earliest mining era and led to the rush that never ended. This and subsequent mining periods have had significant, widespread impact on local and national economic development, settlement, and social conditions.

Jan 1, 1993

Mr. Address Member is hereby proposed by the undersigned, as a Associate Junior Member of the American Institute of Mining Engineers. Signature of three Members or Associates (not Junior Members). Place of birth Year of birth Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates. Please give record of experience on following page with dates; for example, in the form used by "Who's Who In America" and similar publications.

Jan 12, 1917

By J. C. Glandus, N. Tessier-Doyen, M. Huger

The Young's modulus of bi-phased model materials (vitreous matrix containing spherical alumina inclusions) have been determined by two complementary approaches: experimental and analytical. If the matrix and inclusions exhibit close coefficients of thermal expansion, the experimental results lie in the vicinity of the lower bound of the Hashin & Shtrikman's model. If there is a dilatometric disagreement between the components, untypical behaviors, similar to those obtained for a family of industrial refractory materials, were observed when the temperature varies.

Jan 1, 2004

Mr. Address - Member is hereby proposed by 'the undersigned, as a Associate Junior Member of the American Institute of Mining Engineers. Signature of three Members or Associates (not Junior Members). Place of birth Year of birth Education, when, where and how acquired, with degrees, if any. A technical education is not requisite for membership. Dates . . Please give record of experience on following page with dates; for example, in the form used by "Who's Who In America" and similar publications.

Jan 2, 1918