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By I. Abdullayev, M. Soberano Capistran, J. Garcia

The application of post-tensioning in segmental structures was introduced in the early 1900s and has been successfully applied in different types of structures including immersed tunnels, bridges, buildings, metro stations, and stadiums. There are, however, only five known circular concrete tunnel projects where the post-tensioning approach has been adopted. This paper discusses the application of post-tensioning to mitigate the high internal operating pressures in an effluent outfall tunnel project 7 miles, 11.3 km long, currently under construction for the Los Angeles County Sanitation Districts, LACSD. This project will be the first use of post- tensioned segmental concrete tunnel linings in North America.

Jun 23, 2024

By C. Kunze

ABSTRACT Although closure sureties cover works that are carried out during the existence of a mining company, certain liabilities are not known when the surety is established and become apparent only in a late stage of the closure phase, or even after the site has been relinquished. This paper supports the concept that these financial risks lend themselves to insurance solutions. Making insurance for unknown liabilities mandatory while defining unambiguous legal conditions could create a viable market for insurance products, provide a sufficient statistical basis for the calculation of premiums, and reduce costs.

Jan 1, 2013

By A. Moergeli, Philip Sander, John J. Reilly

"Estimating and managing the costs of complex infrastructure projects – in the planning/design and construction phases, for both owners and contractors – has been a challenge for decades. The more complex and technologically advanced the project, the greater the uncertainty, including potential risks that are important to owners and contractors, such as:• Cost risks to owners – meeting budget and schedule, maintaining public credibility.• Cost risks to contractors – profit, consequences of loss, impacts to reputation/future work.This concern has been addressed in various ways by the underground construction industry for some time (Reilly, 2001). In particular, while significant advances have been made in cost estimating for the planning and design phases (Reilly et al., 2004), that are important to agencies and political decision-makers, it is not apparent that these advances have been widely adopted for construction cost estimates. The reasons for this may relate to lowbid considerations – any method that tends to increase the contractor’s cost estimate, by including risk or likely costs, could lead to an erosion of the contractor’s competitive position – if others are not similarly required to include such costs.Different cost estimating methods produce different levels of information. Specifically, there is a large difference in the character and depth of information if a deterministic (quantities times price plus a contingency) and risk-based cost methods are used. It is this difference in character and depth of information that is the reason that risk-based cost estimating has potential value for owners and contractors. Figure 1 presents hypothetical cost results from deterministic and risk-based methods and illustrates some of these differences.In Fig. 1, the results for deterministic and risk-based cost estimates are given related to the potential profit or loss for a typical project. As is evident in this example, there is significant potential for costs to be realized that are higher than the proposal/bid value estimated using a deterministic approach, with a 15 percent probability of a loss. There is a 30 percent probability that the project will have a reduced profit. There is a 55 percent probability that the project will return a good profit. Using a risk-based approach, it is possible to better recognize this potential outcome in the bid phase and, as a consequence, develop a strategy to:"

Apr 1, 2016

By AIME AIME

THE list of deaths during the year 1906 comprises the following names, the figures in parentheses indicating the year in which the persons named were elected to membership Members and Associates.-Arthur Vaughan Abbott (1882), William Anderson Akers (1889), R. Scott Allen (1905), George H. Arlett (1900), Thomas Septimus Austin (1883), Thomas T. Baker (1887), William Tittley Batchelor (1902), Charles Lowthian Bell (1897), Edgar Vallentine Bensusan (1892), George Lothrop Bradley (1874), Ernst Elmer Breisch (1896), Horace F. Brown (1895), James A. Burden (1876), Alexander B. Coxe (1880), George A. Crocker (1879), Albert W. Fiero (1886),

Jul 1, 1907

By Michael N. Maltezos

"There is certainly no argument that LED lighting systems have taken a strong foothold in the lighting marketplace over the last several years. This has even proven true in the world of transportation and transit lighting, for which new LED cobra head style luminaires are replacing traditional HID cobra head luminaires on North America’s roadwaysand linear LED light fixtures are replacing conventional linear fluorescent light fixtures in North American rail transit facilities. However, LED technology has taken a while longer to penetrate the very specific market of vehicular tunnel lighting in this continent. Though both the New York/New Jersey Holland and Lincoln Tunnels have recently been retrofitted with LED lighting, and an LED Lighting RFP is currently out for Boston’s Central Artery Tunnels, very few vehicular tunnels in North America to date have been illuminated with LED light fixtures. This is largely because cost effective LED lighting, that met our typically stringent tunnel lighting standards, was until recently simply unattainable. However, with the rapid advances in LED technology over recent years, owners and specifiers of North American tunnel lighting projects have finally begun to adopt LED lighting systems as the norm. In fact, a recent Lux Fit/Yole Development “LED in Road and Street Lighting Report” stated that “LED luminaire growth will be driven firstly by tunnel lighting, and then relayed into highway, road, residential and amenity lighting applications starting in 2014.” 1 Our highways are continually becoming more congested. As a result, Provincial and State Departments of Transportation (DOTs) are constantly looking for innovative ways to improve traffic flow. One way DOTs are now helping to ease congestion is by expanding the use of tunnels and long underpasses in large interchange reconstruction projects. With less available right-of-way to work with, and the high costs of maintaining elevated bridge structures over the years, it often makes more sense to “go under” (rather than over) the traffic congestion points. With the addition of these new tunnels and long underpasses comes the issue of proper illumination within these structures, for a safe and efficient driving task. DOTs use recommended lighting practices and guidelines for highway lighting, which include specific criteria for tunnels, set by either the Illuminating Engineering Society of North America (IESNA) or the American Association of State Highway and Transportation Officials (AASHTO). However, both IESNA and AASHTO point out that these recommended practices and guidelines are not a mandate, and DOTs are free to make their own decisions about lighting criteria. Accordingly, effectively illuminating tunnels is often times a challenge. This paper will examine the key considerations of the tunnel lighting application in generalas well as what LEDs now bring to the table and how, accordingly, traditional lighting technologies will be phased out in the future illumination of tunnels."

Jan 1, 2016

By E. H. Burroughs

This bulletin is the sixth in the series of petroleum bibliographies published by the Bureau of Mines, Bulletins 149, 165, 180, 189, and 216 being compilations for the years 1915, 1916, 1917, 1918, and 1919- 1920, respectively. In this bulletin the same general plan has been followed in arranging the references, but one or two additions have been made in the classification.

Jan 1, 1921

By C. D. Secrest

Visiting Spring Canyon, a historic coal mining district near Helper, Utah, I was impressed by the great accomplishments that had taken place there. A tour book of the region tells of a period that began in the early 1900's, when the land was still very much the Old West, when settlers lived out their lives in coal company towns and produced a resource that was to build a nation (Cunningham, F., 1990). Between 1912 and the early 1970's, 11 mines had come and gone in that narrow canyon less than 15 kilometers long. Spring Canyon is a historic district now, but I could not dwell too long on the richness of its history. I was there to look for evidence of PCBs.

Jan 1, 1993

By A. W. Newberry

The Virginia copper district is situated in North Carolina and Virginia. It contains many mines and prospects that were active at the turn of the nineteenth century. The Bureau of Mines, as part of the strategic-minerals program, began a project in September 1942 to investigate and explore the most promising of the mines in the district. The Seaboard, High Hill, Durgy, and Blue Wing mines were the sites of the main project activity. This report deals principally with these four mines. Drilling did not discover any new ore shoots but indicated the persistence of known ore shoots in depth. There appears to be no indication of impoverishment of copper with depth.

Jan 1, 1948

By Mervin D. Marshall

A quick-reaction, mine permissible rescue vehicle (MERV) was developed for use by rescue teams. The MERV is a 6-wheeled, battery-powered unit with life support equipment and instrumentation; designed for a two-man team, with provisions for handling two victims or tools in a trailer. The vehicle is 100 inches long, 56 inches wide, and maximum height of 34 inches. It can be lowered down most mine shafts and has clearance to travel mine railways. The vehicle has power to all six wheels with power transmitted separately to either or both sets of wheels. Low-pressure, high-traction tires give the vehicle the ability to handle soft, muddy mine floors, flooded areas and significant obstacles, and can negotiate a 45% grade. Power and life support are sufficient for a 4-hour mission. The life support system is a commercially-available, approved unit currently used by MESA rescue personnel. A payout wire system provides communication between the vehicle and home base over a distance of 10,000 feet. On-board monitoring of carbon monoxide, methane and oxygen is provided, with master and individual alarms to warn of gas concentrations outside pre-set limits. A lightweight, water-tight trailer was developed for carrying victims or hauling tools and equipment.

Jan 1, 1979

MR. McKEEVER: I think we had to start some- where. The proceeds of the beltbuckles and hard hat stickers will certainly be a beginning in a scholarship for some of our young people. And maybe, you know we might even get one of them sometime to go to the University of Oklahoma. A few years ago the luncheon speaker for tomorrow, Brooks Mitchell, got a few of the mine presidents together and we spent a full five hours of just dedicated listening to Carl Terzian. We listened basically on three subjects: how to work with the media, how to work with image, and how to identify with our political systems and those who are in them. I remember that as one of the turning points in my perspective on how our system really works. This gentleman who will be addressing you today, Mr. Terzian, will be conducting about a three-hour session tomorrow. And it's a shame that our other activities will not allow some of the golfers to probably be there. Those of you who can come to the session tomorrow morning will find it most rewarding. A little bit later on we will also have a panel session. And I see all of the panelists are here except for Bob Golten, but I understand that he is registered. We should have a full afternoon session with Charlie and his panel. When we started working on this, we naturally went back to Carl Terzian to give us some guidance. If there is anything wrong with your session, it's my fault because he knows how these should be done and he guided us along the way. One thing that I am sorry, it wasn't his fault necessarily, is that Harry Reasoner will not be with us for lunch tomorrow. Brooks Mitchell is going to make all of the PR he can out of the fact that Harry got scratched and he got in place for him. Brooks gave me one comment along that line. He said, "Do you know what you get when you cross a gorilla with a computer"? Of course I bit on that. He said. "Well, you get a Harry Reasoner." A little over a month ago I was invited out to California to Woodbury University at Carl Terzian's insistence. I happened to be sitting by one of his vice presidents. It was a formal affair. We had to wear tuxedos and everything and Mr.Green was sitting there and he said, "You know," he didn't know who I was at that time, but he said, "You know Carl really didn't want this formal affair. Said he had a couple of friends coming from the coal mining industry and they wouldn't know what to do with tuxedos." So with that Carl, we will start this little session and it's your mike. MR. TERZIAN: Thank you very much Ira. Let me begin by expressing my appreciation to the men and women of the Institute for allowing me to be here. I'm deeply concerned about my reputation, my image and don't want you to get the inference that I am responsible for Ira McKeever's image. Nobody could be responsible for that! But it is a great case in point that we all should be concerned about our images. I guess tomorrow morning from about 8:30. a.m. to about 11:30 a.m. we are going to do a? hopefully, a productive and very pleasant expertence for all of us in this growing field and great interest that people have in the area of image. I happen to be from Los Angeles. I have a national firm which has handled about 600 corporations', over the years through the areas of public relations,' community, civic involvement all built around a strengthening and safe guarding our precious, free enterprise system. And the message that I hope to give you, as you will be eating your lunch today, is really not so much about the image of individuals but as the attitudes built on what Bill Banowsky

Jan 1, 1982

By A. George Stern

The literature dealing with the drilling of oil wells has become extensive during the last few years, and oil men can find much information relating to drilling muds in the technical literature of the petroleum industry. Although large tonnages of clay are used in preparing drilling mud (also known as drilling fluid), almost no information has been published to apprise the clay industry of the types of minerals used, with their requirements and limitations. It is from this point of view that the present report has been prepared.

Jan 1, 1941

By S. Kraemer

Consumption of plastics has been growing in both the U.S. and world markets since the mid-1930s. This growth is due to plastics being used to make new products and as a replacement material for existing products. This paper develops an understanding of the replacement process by looking at the use of plastic, specifically PVC, in the construction pipe industry. History details the growth of the plastics industry and a discussion of the material selection process indicates the advantages and disadvantages of plastic pipe. Analysis shows that the use of plastic, as an alternative material for pipe, is having a significant effect on the cast iron, copper, clay, and steel industries. For the purpose of understanding the replacement process, three example residential systems were examined with a lifecycle cost analysis being performed. PVC was the material of choice in 1988 for all systems. Even though disposal cost was the one area where PVC was not the most cost effective, disposal costs were not sufficient to offset the overall advantage of using PVC on an economic basis. That plastic competes effectively with other materials, in terms of material properties and cost, indicates that further work should be performed to understand the impact plastics have on other material markets.

Jan 1, 1991

By E. C. Lane

This paper is the first putt of a report giving the results of the Bureau of Mines' twenty-third semiannual survey of motor gasoline marketed in the United States. A companion report, Part II, is in preparation and will give a more detailed discussion of the whole survey. Results of the determination of copper-strip corrosion, color, sulphur content, copper-dish evaporation residue, and gum content as given by the Bureau of Mines steam-oven method will be presented in the second paper, which will also include the prevailing retail price and the tax at the time the sample was taken. This paper deals specifically with data relative to gravity, Reid vapor pressure,' and distillation (method 100.13).6 The samples tested were divided into "competitive-price gasolines" and "premium-price motor fuels," a method of presentation that was begun with the twenty-second semiannual survey. A total of 312 samples were collected from service station pumps in 20 cities throughout the United States. Of this number of samples, 207 were "com-petitive-price gasolines" and 106 were "premium-price motor fuels." All of the samples were collected in March, 1931, and analyzed at the Petroleum Experiment Station of the United States Bureau of Mines at Bartlesville, Okla. "Competitive-price gasoline" includes those fuels that are sold at the generally recognized local base price and all fuels that are sold below that price. All fuels that are sold at an advance over the generally recognized base price are placed in the class of "premium-price motor fuels." These fuels include Ethyl gasolines, benzol blends, "high-test" fuels, and those fuels that owe their "anti-knock" rating to the process of manufacture rather than to the addition of other material such as Ethyl fluid or benzol. The term "high-test" is generally applied to motor fuels that are more volatile than the regular competitive-price gasolines. "High-test" fuels may also have a high anti-knock rating.

Jan 1, 1931

By M. B. B. Research Council of Alberta Crockford

Introduction Kootenay strata of Lower Cretaceous age contain much of the highest rank coal produced in Alberta. These strata outcrop in the foothills and mountains of southwestern Alberta and southeastern British Columbia, and the economic value of the coal seams contained in them was evident to the earliest explorers, who refer co them in their journals. Lacer, investigation of the .coal measures was undertaken by prospectors and by a succession of geologists, most of whom were in the employ of the Federal government, but some acted for private interests. Surveys by these men proved chat foothills and mountain regions hold immense quantities of high-grade coal within easy reach of transportation facilities, and their conclusions have accelerated the development of the coal-mining industry m Alberta. Among geologists who have contributed much to our knowledge of the region are J. M. Dawson, G. M. Dawson, R. C. McConnell, D. B. Dowling, J. D. Mackenzie, B. Rose, J. R. Marshall, B. Rose, J. R. Marshall, B. R. McKay, J. A. Allan, and J. L. Carr. The present paper is to a great extent a compilation of the work of the above men and of several others who have investigated the area lying between Bow river and Crowsnest pass. Space does not permit a list of all the sources of information so chat only chose of prime importance are given in the text. Data for the map and ?cross-sections of Figure 1 were taken from the following published maps of the Geological Survey of Canada: Cascade Coal Basin, Pub. 933; Canmore, Maps 322 and 323; Upper Elk River and Upper Highwood Rivers, Pub. l980; Blairmore, Pub. 1584; Southfork Coal Area Map l03A; and of the Research Council of Alberta: Highwood-Elbow Area, Map 20; and Ribbon Creek Area, Map 21. In some cases, the cross-sections have been simplified or otherwise altered, and for these revisions the writer cakes full responsibility. The stratigraphic sections of Figure 2 have been taken from published reports of the above mentioned organizations. The area covered in this paper is shown in Figure l. It is wholly within Alberta, and reaches from township 5 to township 27 and from range 1 co range 11, west of the fifth meridian. Its location is about fifty miles west of both Calgary and Lethbridge. Topography of the area ranges from foothill on the east to mountainous on the west. In this paper' the foothill region is considered to be chat which lies immediately east of the most easterly mountain ranges, such as Livingstone and Highwood. There are two principal coal mining districts in the area, one served by the main line of the Canadian ?Pacific railway and centring about Canmore, the other by a branch line of che same railway and centring about Bellevue, Blairmore, and Coleman.

Jan 1, 1949

By A. C. Wallace

THE development of the natural resources of any district of any magnitude, inevitably gives rise to many problems off title, usually due to the greatly enhanced value of the land. The development of the mining industry in the Quapaw Agency has been no exception to this general rule. Our problems, how-ever, have not been many or particularly serious. The Quapaws were allotted and patents issued by the United States Government in 1895. These patents contained a restriction against alienation for a pe-riod of twenty-five years. The effect of the restric-tion was to prevent the Indian from selling, leasing, or in any way encumbering his land. The Govern-ment, in a paternalistic spirit, sought to teach the Indian thrift and industry and to insure him a place of residence. This is evidenced by the first Leasing Act passed by Congress, which permitted only incom-petents and those physically disabled to lease their land for either agricultural or mining purposes. The able-bodied Indian was denied the right to lease. It soon became apparent to the Government, how-ever, that this was a mistaken policy, and in 1897 a General Leasing Act was passed by Congress and it was under this act that the mining industry in the Quapaw Agency was developed. The act, reads as follows: "That the allottees of land within the limits of the Qua- paw Agency, Indian Territory, are hereby authorized to lease their lands, or any part thereof, for a term not ex-ceeding three years, for farming or grazing purposes, or ten years for mining or business purposes. And said al-lottees and their lessees and tenants shall have the right to employ such assistants, laborers, and help from time to time as they may deem necessary: Provided, That when-ever it shall be made to appear to the Secretary of the Interior that, by reason of age or disability, any such allottee cannot improve or manage his allotment properly and with benefit to himself, the same may be leased, in the discretion of the Secretary, upon such terms and conditions as shall be prescribed by him. All acts and parts of acts inconsistent with this are hereby repealed." It was the interpretation of this Act that gave rise to our first serious problems. It will be noted that the Act says that "allottees of land" within the limits of the Quapaw Agency are authorized to lease their land. Thus, the first question was presented by the use of the term "allottee," and the question was as to whether or not Congress intended to limit the Quapaw Indian to the leasing of his own allotment or did Congress mean that the term "allottee" was synonym-ous with "Indian" and intend to give the Indian a right to lease both his allotment and his inherited land and was an Indian without an allotment an "allottee" even though he was a member of the Qua-paw tribe and the owner of the Quapaw land by in-heritance, and not being an allottee, could he lease his inherited Quapaw land under the authority granted in this Act?

Jan 5, 1928

By Marvin P. Barnes, John G. Simos

The Park City District, Utah, is situated in the Wasatch Range at the intersection of the westward extension of the axis of the Uinta Range. Ore has been mined almost continuously from the first discovery in 1869 to the present day, with a total production of over 14 million tons. Sediments of Carboniferous to Triassic age have been folded into the northerly plunging Park City anticline and subsequently modified by thrust faulting, diorite and diorite porphyry intrusions, and strong east-west normal faulting during the Laramide orogeny. Younger andesitic volcanics partially cover the eastern edge of the district. The ore bodies occur as both lode and bedded replacement deposits over widely scattered localities. Near surface, high-grade silver "bonanza" ores were mined in early days from the Ontario and Daly Lodes, which occur along the east-west zone of faulting near the center of the district. Other lode or fissure deposits were found along the Mayflower and Hawkeye faults to the east and southeast. Large bedded replacement silver-lead-zinc ore bodies associated with east-west zones of fissuring, have been mined from favorable horizons in the Park City Formation in the Daly West and Judge mines. A series of long, narrow, high-grade, replacement ore bodies occur in the Silver King mine at a single horizon in the Park City Formation. Ore is currently being mined from strong bedded replacements in the Humbug Formation near the apex of the Park City anticline. Factors controlling ore deposition are: magmatic source, structural feeder systems, and favorable host rocks. Ore deposition along favorable beds is primarily a function of physical conditioning and secondarily of chemical composition.

Jan 1, 1968

By John C. Machisak

Injury data and experience, with related employment statistics, at coal mines in the United States for 1960 are presented in this publication under the following general sections: A General injury experience: Tables 1 to 6: Current data on number of injuries, decree of injury, frequency and severity rates, average severity, and related employment and production data by work location. B Selected injury experience: Tables 7 to 38: Current data on principal agencies of injuries, distribution of injuries by part of body injured, days of disability, extent of hand and machine loading, experience by employment and production groups, and various other operating factors and physical conditions related to the occurrence of injuries at the Nation?s coal mines.

Jan 1, 1962

By Louis C. Srichta

The rapid depletion of known high-grade ore deposits of the Tri-State district and the recognized need for development of additional reserves, together with increased interest in open-pit mining of low-grade zinc-lead ores led to Bureau of Mines examination of several abandoned mining areas for possible deposits adapted to strip mining. Examination of the North Empire tract in Cherokee County, suggested that mineralized zones contiguous to previously mined 2e deposits presented probabilities of meeting the requirements for an open-pit mine - hence the tract was selected for further investigation by churn drilling. The zinc-lead deposit on the property is in a sink-hole structure that has been subjected to intense deformation and silicification. Numerous shafts, mine dumps, and surface caves are evidences of exploitation of an extensive area. The reported active mining period was 1895 to 1905. No production records are available, but it is generally stated locally that the value of the mill products exceeded $2,000,000 which represents considerable production, considering the low metal prices of that epoch.

Jan 1, 1950

By George Mixter

MINING, in contrast to manufacturing, deals with a wasting asset. That which is taken out of the ground is gone, the property is depleted to that extent, and will eventually become exhausted of profitable ore. So the life of a mining company is dependent upon the ability of its management to develop improved methods to permit extraction at a profit of the lower-grade ores which remain, to extend by intelligent exploration the limits of its known ore bodies, and to find and acquire new properties to take the place of those that, for one reason or another, are no longer operated. Its history is a story of constant change, of the working out of properties here and the acquisition and development of properties there, to maintain the vitality of the whole. It is a story of estimating with the tools and the knowledge available the location and extent of hidden ore bodies and of devising the means of extracting

Jan 1, 1948

"TREVIICOS CorporationINTRODUCTIONThe Walter F. George lock and dam was constructed on the Chattahoochee River between 1955 and 1963 with the double function of improving navigation and generating power. Its 82 ft. by 450 ft. (25m x 137m) lock can accommodate large barge traffic and its four generating units with a plant capacity of 150 MW have an average energy output of 453,000 MWH. The dam consists of a 1,496 ft. (456m) long concrete structure housing the spillway, a non overflow portion, the power units and two earthen wing dams extending to the Georgia and Alabama sides, respectively 5,810 feet and 6,130 feet long (1770m and 1868m). As soon as the reservoir was impounded it became apparent that excessive seepage was occurring. From 1962 to 1985 a series of remedial works was performed using several techniques, but the problems continued under the dam, jeopardizing its generating potential and possibly undermining its stability.Finally, the decision was made to construct a deep cutoff primarily under the concrete portion of the dam to remedy the problem. PROCUREMENTOn July 5th, 2001 best and final offers were solicited by the Corps of Engineers (COE) for the construction of a deep cut-off to be built in front of the concrete portion of the dam from the bottom of the lake and tied into it. The cut-off had to cross an existing lock structure and an underwater retaining wall, as well as the remnants of a steel coffer cell left in place from the initial construction.The specifications required that the wall be built with a minimum thickness of 24” (600mm) and that it extended from the bottom of the lake to elevation -5 (1.52m) into the Providence formation, an impervious layer.While the land portions of the wall were on average 208 feet (63.4m) deep, the marine portion started from up to 90 feet (27m) of water and continued through different rock formations for another 100 feet (30m).Contractors were invited to propose their own method of constructing the cut-off and offers would be evaluated using several criteria, including technical, economical, organizational and experience.Three proposals were received and on August 14, 2001 an award was made to the Joint Venture (JV) of Treviicos and Rodio."

Jan 1, 2014