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By L. P. Weber

During the years 1983-1987, a research programme, jointly performed by the steel producers ARBED, British Steel Corporation, Peine-Salzgitter, Unimetal, and co-sponsored by the European Community for Steel and Coal (ECSC), has been carried out on steel H-piles of different shapes. The initial aim of the testing programme has been the improvement of bearing capacity, both in sandy and clayey soils. At two test sites, standard H-beams are compared to H-piles with different types of laggings or to H-piles grouted both under low and high pressure. In this paper and in view of the open european market in 1992, the H-pile capacities and their corresponding allowable loads, determined from codes, recommendations and computation procedures in use in Belgium/Luxembourg (B/L), France (F), Federal Republic of Germany (G), and the United Kingdom (UK) as well as their evaluation from dynamic CAPWAP and Case methods are compared to the static capacities measured in-situ. In addition, procedures for estimating the load/movement behaviour of H-piles from CPT, pressuremeter, and CAPWAP are compared to the measured curves.

Jan 1, 1991

By F. Seitz

STAFF: Editor, Gerhard Derge Carnegie Institute of Technology Schenley Park Pittsburgh 13, Pa. Editorial Assistant, M. A. Redmerski Managing Editor, James J. Burke THE METALLURGICAL SOCIETY: John Chipman, President; W. R. Hibbard, Jr., Post-President; C. C. Long, Vice-President; T. D. Jones, Treasurer; R. W. Shearman, Secretary. PUBLICATIONS COMMITTEE OF THE METALLURGICAL SOCIETY: R. Maddin, Chairman; Dennis Carney, J. C. Fulton, J. H. Hollomon, T. B. King, C. C. Long, W. 0. Philbrook, J. D. Sullivan, David Swan, and F.L. Vogel. Review and selection of manuscripts is under the supervisian of the following Publications Committees: Extractive Metallurgy D ivis ion: T. 0. King, Chairman; S. J. Dick inson, R. P. Hermsdorf, R. Schuhmann, Jr., and H. H. Kel logg. Institute of Metals Division: F. L. Vogel, Choirmon; R. L. Smith, Vice Chairman; R.W. Balluffi, J. H. Bachtold, A Servi, C.D.Graham, Jr., C. G. Goetzel, F. E. Joumot, Jr., G. E. Pellissier, Paul Gordon, Jock Washburn, Harold Margol in, A. U. Seybolt, I. R. Kromer, R. A. Meussner, R. W. Guard, M. Harmon, J. N. Hobstetter, Dean Starr, P. Shewmon, R. Gordon, J. 0. Betterton, and E. Morgan. Iron and Steel Division: W. 0. Philbrook, Chairman; F. C. Langenberg, C. W. Sherman, J. Wagstaff, and E. J. Whittenberger. Published bimonthly by the American lnstitute of Mining, Metallurgical, and Petroleum Engineers, Inc., 29 West 39th Street, New York 18, N. Y. Telephone: PEnnsylvania 6-9220. Subscription $20 per year for non-AIME members in United States and North, South, and Central America; $25, foreign; $5 for AlME members. Single copies, $4.00, single copies foreign, $5.00. The AlME is not responsible for any statement made or opinion expressed in its publications . . . Copyright 1959 by the Americon Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. . . . Registered cable address, AlME New York ... Indexed in Engineering Index, Industrial Arts Index, and Chemical Abstracts . . .Second class postage paid at New York, N. Y. , ond Ann Arbor, Mich. Volume 215, Number 3

Jan 1, 1960

By Harry E. Hughes

A section of the largest Superfund site in the country has become a success story for engineering innovation and for cooperative problem solving. “Superfund site” and “success story” are phrases that are not commonly found in the same sentence. Yet, their use seems justified. The project’s certification of construction completion from the US Environmental Protection Agency (EPA) includes a commendation. It reads, “for completing the project nearly a year ahead of schedule, at a cost substantially less than estimated originally and without com-promising the requirements for protection of human health and safety or the environment.” The EPA director who issued that certification also referred to the project as “a positive example of cooperation among all who have a stake in the outcome.”

Jan 1, 1996

By John L. White

Vibratory driver/extractors do more than drive and extract sheet piles. I would say more than sixty percent (60%) of the time, vibratory pile driver/extractors are engaged in work that has nothing to do with sheet piles. This is the main reason I refer to this tool as a "driver/extractor", and omit the word "pile". I have spent the last twenty years applying the technology of the vibratory driver/ extractor to all areas of foundation construction. As you will see, the only limits are humankind's ingenuity.

Jan 1, 1997

By R. G. Horvath

The Statnamic loading test is a new and innovative method for testing deep foundations. The test is relatively inexpensive, quick, easily mobilized, provides for direct measurement of applied load and corresponding displacement, and is capable of very high loading capacities. The long duration of the applied loading, as compared to a dynamic loading test, allows for a straightforward determination of the static behaviour of the foundation tested. A new method of analysis of the Statnamic loading test, the Equilibrium Point Method, is presented. A description is given of the pile-soil model and a demonstration of how the static load-displacement behaviour of deep foundations may be predicted from the Statnamic loading test data. The Equilibrium Point Method of analysis is applied to three types of deep foundations in soils which respond differently to fast loading rates. These case histories, from Canada and the United States, include data from static loading tests for direct comparison, and demonstrate the ability of the Equilibrium Point Method to predict static behaviour of the deep foundations.

Jan 1, 1993

By Michael W. Oakland

Deer Island is the site of the Massachusetts Water Resources Authority (MWRA) wastewater treatment plant which, when completed in 1999, will serve 43 cities and towns in central eastern Massachusetts. Deer Island is located in the Boston Harbor, as shown on Figure 1. The existing wastewater treatment plant on Deer Island is being upgraded to include secondary treatment to comply with Federal require­ments. The new treatment facilities will process an average of 455 million gallons of sewage per day; total capacity will be about one billion gallons per day. The new treatment facilities will cover virtually the entire island. [ ]

Jan 1, 1994

By Rudy J. Matetic

Over-exposure to noise remains a widespread and serious health hazard in the U.S. mining industries despite 25 years of regulation. Every day, 80% of the nation’s miners go to work in an environment where the time weighted average (TWA) noise level exceeds 85 dBA and more than 25% of the miners are exposed to a TWA noise level that exceeds 90 dBA, the permissible exposure limit (PEL). Additionally, MSHA coal noise sample data collected from 2000 to 2002 show that 65% of the equipment whose operators exceeded 100% noise dosage comprise only seven different types of machines; auger miners, bulldozers, continuous miners, front end loaders, roof bolters, shuttle cars (electric), and trucks. In addition, the MSHA data indicate that the roof bolter is third among all the equipment and second among equipment in underground coal whose operators exceed 100% dosage. A research program was implemented to: 1) determine, characterize and to measure sound power levels radiated by a roof bolting machine during differing drilling configurations (thrust, rotational speed, penetration rate, etc.) and utilizing differing types of drilling methods in high compressive strength rock media (>20,000 psi). The research approach characterized the sound power level results from laboratory testing and provided the mining industry with empirical data relative to utilizing differing noise control technologies (drilling configurations and types of drilling methods) in reducing sound power level emissions on a roof bolting machine; 2) distinguish and correlate the empirical data into one, statistically valid, equation, in which, provided the mining industry with a tool to predict overall sound power levels of a roof bolting machine given any type of drilling configuration and drilling method utilized in industry; 3) provided the mining industry with several approaches to predict or determine sound pressure levels in an underground coal mine utilizing laboratory test results from a roof bolting machine and 4) described a method for determining an operators’ noise dosage of a roof bolting machine utilizing predicted or determined sound pressure levels.

Jan 1, 2006

By Holger Witthaus

Various seam conditions had been examined during longwall production at RAG German hard coal mines. Based on the field data a prediction method was developed considering separation planes as influencing factors for roof falls at the face. The characteristics, orientation, and density of separation are important factors on the occurrence of roof falls. In addition to geological influences, the performance parameters and geometry of support must be considered and optimized for the prediction and prevention of roof falls in a longwall face. Based on detailed macro- and microscopic investigations of e coal seams considering various ranks of carbonization, the origin and characteristics of separation planes are determined and a strata-specific influence on roof fall is interpreted. It was assessed that the coal face fracturing and displacement caused by the stress depend on the floor and roof strata conditions due to activation of the existing separation planes. Field studies are shown giving an idea of influences by advance rates of the longwall face, support delay and hydraulic pressure to the roof control in longwall faces in depth of more than 3000 ft. The analysis includes the application of specific software developed for longwall roof fall prediction as a result of a European research project. The software allows a laminar graphic display of roof fall probability, which is used for recognition of risk areas and risk management.

Jan 1, 2009

By M. D. Max, A. H. Johnson

INTRODUCTION Gas hydrates have considerable potential to be a major energy resource owing to their apparent abundance in Arctic regions and along continental margins throughout the world (Kvenvolden, 1988). Yet, the oil and gas industry has been slow to pursue this opportunity. The primary reasons for this are the large conventional reserve base for natural gas worldwide and the perception that gas hydrate will not be a viable resource for another twenty or thirty years. Gas hydrates are thus viewed as a potential resource for the distant future, but not a valid investment for the near term. This paper addresses both global gas markets and gas hydrate technology, and shows that the commercial development of gas hydrate could proceed rapidly enough to constitute a near-term energy resource. GLOBAL GAS MARKETS The proven worldwide reserves of conventional natural gas are truly enormous, totaling over 6,000 TCF according to BP (2004). Moreover, those reserves have nearly doubled during the past two decades and now represent 67 years of consumption at the current production rates of 80 TCF per year (Fig. 1). This reserve increase has occurred even as global production of natural gas has increased by 67% during the same two decades (Fig. 2). While declining conventional gas reserves are a concern in North America, especially in regions where established infrastructure exists to bring gas to consumers, large new discoveries continue to be made elsewhere in the world. Indeed, in many parts of the world (such as the Middle East and parts of West Africa), natural gas has been regarded as an essentially worthless byproduct of oil production or exists in stranded gas fields. Given this situation, pursuing unconventional gas resources that are inherently riskier exploration targets and more expensive to produce would appear to have little rationale from a business standpoint.

Jan 1, 2006

By Fábio Luiz dos Santos

As ligas de alumínio, em particular, apresentam certas restrições quando submetidas ao processo de união por soldagem. Isto se deve, principalmente, por apresentarem elevada condutividade térmica, elevada contração na solidificação e elevada solubilidade de hidrogênio. Levando em conta estes aspectos, o processo de soldagem FSW apresenta grande potencial para esta aplicação, visto que, é autógena, realizada sem fusão do material e sem utilização de escórias ou gases de proteção. A partir deste conceito, o objetivo do presente trabalho é avaliar a união de chapas finas de alumínio da liga 3105 H26, com espessura de 0,7mm. Para realização dos testes, foram analisados fatores como: penetração da ferramenta nas chapas processadas, ângulo de ataque, tipo de ferramenta e modo de controle de penetração (posição ou força). Os resultados indicaram que o modo de controle por força se mostrou o mais indicado para chapas finas, e que o regime transiente no início de soldagem foi a parte mais crítica para controle da qualidade da junta soldada.

Aug 16, 2017

By Mohammad Nasim

Vertical expansion of existing structures frequently requires foundation retrofitting to enhance the capacity of existing foundations for supporting additional loads. Owing to their small diameter, a variety of suitable drilling methods available for installation, and smaller installation equipment capable of operating under limited headroom conditions, micropiles are often preferred for foundation retrofitting. This paper presents a case history demonstrating application of micropiles to underpin the existing foundation of the Washington D.C. Children?s National Medical Center (CNMC) for its future expansion. Located at 111 Michigan Avenue in northwest Washington, DC, portions of the hospital currently extend five stories above grade and three levels below-grade as parking garages. The hospital intends to expand the surgical wing up to the current build out (five stories) above the remaining portion of the existing parking garage. The original foundations consist of 80-ton Raymond Step-Tapered piles. New loading on the foundations required each Raymond pile to be capable of supporting 150 tons. Results from quick load tests on existing piles indicated that two entire column lines (Column Line A and B) would experience loads beyond their capacity, requiring enhancement of the existing foundation at these locations. The design and construction of the foundation upgrading work was particularly challenging due to various project constraints related to a high groundwater table, micropile installation under limited head room, and ensuring that the parking garage remained fully operational for the entire duration of construction. The paper presents the challenges faced during testing of existing foundations amid a high groundwater table, design developments of underpinning options to support the additional column loads, difficulties and challenges encountered during installation of the micropiles and construction of the micropile pilecaps, and value engineering options developed during various phases of the project. Understanding that micropiles are often a preferred option for foundation retrofitting, the case history is expected to provide a baseline design approach and innovative solutions to typical challenges faced during construction, thereby reducing potential cost overruns during design development and construction of similar future projects.

Jan 1, 2008

By Ihsan Berk Tulu, Mark Van Dyke, Ted Klemetti, Deniz Tuncay

"Longwall abutment loads are influenced by several factors, including depth of cover, pillar sizes, panel dimensions, geological setting, mining height, proximity to gob, intersection type, and size of the gob. How does proximity to the gob affect pillar loading and entry condition? Does the gob influence depend on whether the abutment load is a forward, side, or rear loading? Do non-typical bleeder entry systems follow the traditional front and side abutment loading and extent concepts? If not, will an improved understanding of the combined abutment extent warrant a change in pillar design or standing support in bleeder entries?This paper details observations made in the non-typical bleeder entries of a moderate depth longwall panel; specifically, it explores data collected from borehole pressure cells and roof extensometers, observations of the conditions of the entries, and numerical modeling of the bleeder entries during longwall extraction. The primary focus was the extent and magnitude of the abutment loading experienced due to the extraction of the longwall panels. Due to the layout of the longwall panels and bleeder entries, the borehole pressure cells (BPCs) and roof extensometers did not show much change due to the advancing of the first longwall. However, they did show a noticeable increase due to the second longwall advancement, a maximum of about 4 MPa of pressure increase and 5 mm of roof deformation. The observations of the conditions showed little to no change from before the first longwall panel extraction began to when the second longwall panel had been advanced more than 915 meters. Localized pillar spalling was observed on the corners of the pillars closest to the longwall gob as was an increase in water in the entries. In addition to the observations and instrumentation, numerical modeling was performed to validate modeling procedures against the monitoring results and evaluate the bleeder design. ITASCA Consulting Group’s FLAC3D numerical modeling software was used to evaluate the bleeder entries. The results of the models indicated only a minor increase in load during the extraction of the longwall panels. These models showed a much greater increase in stress due to the development of the gateroad and bleeder entries—about 80% development and 20% longwall extraction. The FLAC3D model showed very good correlation between modeled and expected gateroad loading during panel extraction. The front and side abutment extent modeled was very similar to observations from this and previous panels."

Jan 1, 2019

By S. Vivek

An atomic force microscope (AFM) was used to measure the surface forces between silica surfaces immersed in solutions of hydrolysable cations and/or sodium oleate. Hydrophobic forces were observed at the pH range where the concentration of the singly-charged hydroxo-complexes (CaOH+ or MgOH+) in solution is the highest. In the absence of oleate, the adsorption of the hydroxo-complexes was indicated by the disappearance of the repulsive hydration force. These results suggest that the hydrolysable cations adsorb on silica as singly-charged hydroxo-complexes. Based on the results obtained in the present work, a model for the adsorption of hydrolysable cations has been developed.

Jan 1, 2009

By C E. J de Ronde, I C. Wright

Oceanic subduction-related volcanic frontal arcs extend over 20 000 km within the western Pacific basin and over 21 500 km worldwide, yet they remain largely unexplored with respect to active seafloor mineralization. Systematic exploration of 26 major submarine volcanoes along ~840 km of the Kermadec arc northeast of New Zealand has documented ten (39 per cent) as being hydrothermally active. This frequency of venting is comparable to that on slow-to-moderate rate spreading mid-ocean ridges, which comprise ~80 per cent of the 60 000 km-long global system of spreading centers. The chemistry of fluids discharged from the Kermadec arc volcanoes is moderated by magmatic components in both the gaseous (CO2 + SO2-H2S) and liquid (Fe) phases at very high concentration.The high frequency of venting coupled with chemically rich discharge discovered during this first systematic survey of any arc system forecasts submarine arcs as being important sources of chemicals to the oceans and as potentially lucrative exploration sites for seafloor mineralization. The exploration protocols developed during these surveys include bathymetric mapping of mostly unknown volcanic edifices, followed by detailed water column profiling and sampling to detect and characterize volcanic fluid emission signatures. These procedures are being refined as the survey progresses, both for efficiency and as direct seafloor observations become available for predictive application of water column plume information to guide seafloor mineral exploration.

Jan 1, 2002

By Barry Olson

The Peñasquito deposit in Mexico is one of the largest grassroots precious metal discoveries to be developed in recent years. Goldcorp Inc. acquired the gold-silver-lead-zinc property with the acquisition of Glamis in 2006. The company has since committed US$1.5 billion to construct the mine, mill and associated facilities. The first of two 50-kt/d (55,000-stpd) mill and flotation lines is currently being commissioned while engineering and construction continues on the second line. A high-pressure grinding roll (HPGR) will ultimately take total throughput to 130 kt/d (142,000 stpd). The Peñasquito property is located in the northeast corner of Zacatecas state, Mexico. The elevation of the property averages 1,900 m (6,200 ft) above sea level and it is situated in a wide east-west valley. Except for one small outcrop (Peñasquito), the area is covered by up to 30 m (98 ft) of alluvium.

Jan 1, 2009

The suitability of char from Yallourn brown coal as a filler for carbon electrodes used in the aluminium smelting industry has been assessed on the basis of the specifications usually laid down by electrode manufacturers for petroleum coke fillers. The purity specifications can be met by a simple acid leaching of the coal before carbonization. The true density of char produced at 1200°C is within 5 per cent of the specification figure, but the bulk density of char obtained from as-mined coal is only half that specified for petroleum coke.Although this can be increased to three-quarters of the specified figure by briquetting the coal before carbonization, further increases would be very difficult to achieve, as the remaining shortfall in density is due to an extensive microporosity developed in the particles of char during carbonization.

Jan 1, 1970

By Jia-Shyan Shiau, Chung-Ken Ho

An uneven gas distribution through the burden layers inside a blast furnace (BF) results in abnormal gas resistance or pressure changes. Rapid variations in the abnormal gas resistance will lead to the occurrence of channeling. A visualization technology mainly made of pressure distribution was developed to predict BF channeling phenomena in this study. The real-time data of BF shaft pressure was used to create a 3D visual model by neural network algorithms and 3D real-time BF pressure changes were observed. The root mean square deviation (RMSD) of the BF shaft pressure was used as an index to set up the predicting criteria of channeling occurrence with the opening of BF Annular Gap Element (AGE), and a predicting system based on the criteria was built. The two criteria for the channeling alarm are the RMSD of the BF shaft pressure (> 0.15 kg/cm2 ) at the upper two levels, and the AGE opening being greater than 60%. This system has been installed in the China Steel Corporation (CSC) BFs, and the test results showed that a prediction can be obtained 8 to 16 min ahead of channeling allowing sufficient time for the operator to adjust the BF operation in order to avoid the occurrence of channeling.

By D. M. Avant, A. J. Solomon, S. M. Pickering, W. R. Fox

Introduction Most high purity silica is produced from crystalline quartz, generally from sand. However, there is a small area of southern Illinois where a porous, friable white chert rock is found that is very different in physical form from quartz sand. This microcrystalline material, commonly referred to as tripoli, is more easily ground to micron sizes than sand. Although of similar Moh's hardness, microcrystalline tripoli is less abrasive than either ground quartz sand or many synthetic abrasives. Location The southwestern corner of Illinois is underlain by extensive deposits of very porous chert; in some places the material is quite white. Two companies, Illinois Minerals Co. and Tammsco Inc., mine and process this white material. The Illinois Minerals plant is located at Elco, and the Tammsco plant is in Tamms, IL. Both companies mine from various locations within a 10-mile truck haul of their plants. Production from this district has been continuous since at least 1915. Malvern Minerals Co. mines and processes a generally similar microcrystalline, friable novaculite near Hot Springs, AR. Geology The southern Illinois white tripoli area is on the southern flank of the Illinois Basin. The commercial silica zone is a facies of the Clear Creek chert of Lower Devonian Age. To the north, where it occurs deep in the basin, the Clear Creek is a siliceous limestone. In the mining area, thin overburden has allowed access by surface ground water, which has leached away the carbonate content and left a quite pure silica residue. Fossils characteristic of sea bottom deposition, such as brachiopods and trilobites, are occasionally encountered in mining. The structure of the mining area is poorly known, due to infrequent outcrops. Strata in most mines are inclined at dips of 5° to 20°. There appear to be occasional high angle normal and reverse faults, but these are seldom of any significance in mining. The friable white silica zone mined in the Clear Creek chert is overlain by dark brownish-red chert and siliceous shale. Exploration drilling to date has not encountered the base of the microcrystalline tripolitic zone. Chemical content Leaching by ground water solution has removed virtually all the carbonate from the original siliceous limestone. Impurities encountered are red to yellow iron oxides, aluminous clays, and occasional black manganese oxides. The silica has no detectable formula water. A typical chemical analysis and physical properties are listed in Tables 1 and 2. Mineralogy and crystallinity Southern Illinois friable tripoli appears amorphous under the polarizing microscope. No crystal structure and only occasional, vague, patchy anisotropism is evident. However, the material gives an excellent quartz X-ray diffraction pattern. Thus, so far as X-ray mineralogy is concerned, the material is clearly

Jan 12, 1986

By Colin Barratt

The East Side Access (ESA) project is the largest underground rail infrastructure project under construction in New York City, USA. The Manhattan segment of the project is to be mined through rock and consists of 4.1 miles of Tunnel Boring Machine tunnels for track work and mined excavations to house rail switches, air plenums, and other rail facilities. This paper considers different methods for concrete lining, such as the use of fixed forms, adjustable forms, and pneumatically applied shotcrete. The advantages and disadvantages of these methods are discussed and the basis for considering one over the other are illustrated. Further discussions on design development and preparation of documents to facilitate quality and constructability in the field are presented.

By W. Sondermann

"AbstractWith the increasing demand in reuse of inner city areas and the urgent need for deeper foundation pits under cramped circumstances, adjacent structures close to and high ground water level, the well-known established technologies especially with small to mid-sized dimensions are often too time consuming and occasionally not economic to install lateral support systems. The alternatives for these specific cases could be the usage of the deep mixing technology to create lateral support systems in reinforcing the deep mixing elements additionally to transfer the horizontal loads from earth – and water-pressure.With increasing demand in depth and water tightness, verticality and overlapping of single column solutions are becoming the key in execution. In addition, for some applications subsoil-conditions were not ideal for wet deep mixing technologies. The tubular soil mixing system (TSM) as a combination of mechanical mixing and support of hydraulic cutting by jet grouting can provide solutions toovercome these challenges.1. Current market conditions and trendsThe present financial crisis and the efforts not only to consolidate national budgets, but also to rescue certain banks, have not left the building industry unaffected either. Some drastic cutbacks to public budgets, along with the increasingly restrictive granting of credit for the financing of construction projects, have led to enormous over-capacities in the building sector, with purely negative impact. As a consequence of these negative developments, many companies are experiencing the pressure to restructure more quickly and to reduce costs but at the same time to keep the consequences of all activities, both externally and internally, within limits acceptable to employees, owners and finance institutions and last but not least consumers."

Jan 1, 2014