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By Harry K. Weatherbee

The paper presents a design case study for a four-story correction facility addition in south Boston, Massachusetts, supported on friction piles driven into the Boston Blue Clay. 356 mm (14-in.) square prestressed-precast (PSPC) concrete piles were selected as they were found more effective and economical. A static load test was performed where the pile was brought to "failure". The load test data were evaluated to estimate the Ultimate Pile Capacity as well as the Ultimate Unit Skin Friction (Adhesion) to serve as a design tool for friction pile projects in the south Boston Area.

Jan 1, 2003

By Debasis Deb

The first version of the longwall strata control and maintenance system (LSCMS) has been successfully developed by the Strata Control Re¬search Team at the University of Alabama. The system includes a software package designed to monitor shield leg pressure, interpret the data and predict the forthcoming roof loads and the existence of geological anomalies. It can also detect maintenance problems of the face equipment. The LSCMS was installed underground and connected to the surface terminals at Drummond's Shoal Creek Mine in Alabama. The system has proven to be a useful and practical system for improving safety and efficiency in coal-mining operation. The Shoal Creek Mine is a new, large coal mine operated by Drummond with two longwall panels. The Blue Creek seam is the primary source of coal production. It is located at a depth of 275 to 440 m (900 to 1,450 ft) below the surface with an approximate 2% southwest dip. Typical strata conditions are represented by two stratigraphic columns (Figs. la and b). A fireclay/dark shale parting (called Middleman) 0.2- 0.7-m- (1- to 2.5-ft-) thick exists between the Mary Lee and Blue Creek seams. Mining conditions vary from area to area. This mainly depends on the Blue Creek seam thickness that ranges from 0.9 to 2.9 m (3 to 9.5 ft). The thickness of the Mary Lee and the parting is relatively consistent with a to¬tal of 0.9 m (3 ft). They are mined when the Blue Creek seam becomes thinner. In most of the panels, the immediate roof is composed of sandy shale 1.5-

Jan 1, 1997

By R. L. Gibson

Manpower competencies in the mining, minerals processing and energy industries in South Africa into the next century will, to a large extent, derive from the nature and quality of the teaching which pupils receive at school. This paper provides an overview of the current developments towards a new National Curriculum in South African Schools and highlights areas in which the Minerals Industry might provide input into this process.

Jan 1, 1997

By Luis Vassallo

El presente trabajo señala los beneficios que pueden obtenerse de la adopción inteligente de una estrategia de colaboración electrónica que responda a las necesidades de este segmento y que proporcione soluciones de verdadero valor agregado. Así, el modelo monolítico que prevaleció por muchos años, donde cada empresa era propietaria de las licencias mineras, operadora, mantenedora, contratista, vendedora, embarcadora y financiera, está desapareciendo. En la cadena de valor del proceso minero intervienen más empresas, contribuyendo valores agregados específicos y especializando funciones. Este cambio demanda mayores flexibilidades de los sistemas de información que deben ser totalmente abiertos, y permitir el intercambio instantáneo de información que facilite reaccionar oportunamente a las diferentes variables de la operación. Por ello, la colaboración electrónica permite a la minería adaptarse a un mundo que está cambiando.

Aug 25, 2002

By Radianto Elprama

For the realisation of the underground railway line RandstadRail in the city area of Rotterdam a bored tunnel is under construction. Diaphragm walls up to a depth of about 40 m were used to construct the building pits for the start shaft, the Blijdorp Station and the end shaft. The water tightness of the diaphragm walls was determined by leakage tests that were executed after the construction of the walls, but prior to the excavation of the building pits. The tests showed satisfactory results with a hydraulic resistance of the diaphragm walls of at least 500 days. To determine the water tightness of diaphragm walls it is recommended to follow the specific procedure as described in this paper.

Jan 1, 2006

By Brian Gar Wingfield

"The introduction of the QuarryMan laser profile system in 1987, along with the development of the corresponding 3-D software, gave a qualified operator pertinent information about dimensions of quarry highwalls, pattern and hole loading design, stockpile profiles, etc . . . Attributes helpful for this endeavor included surveying, computer, and blasting knowledge. Since not all operators had theseskills, a simpler model, the QuarryAce, was designed to look a t highwall dimensions in 2-D view . Al though less sophisticated than the QuarryMan instrument and its software, it is simpler to instruct in its use and has the ability to determine burdens at different depth levels . An in-house user f r i e n d l y computer program was designed to utilize QuarryAce depth vs. burden data . This program was created to enable laser and computer novices to generate information useful to the everyday blaster."

Jan 1, 1992

By John Reilly

Costs of complex/underground projects have been consistently underestimated and delivery on time and on budget has been problematic. This has been attributed, to inadequate cost estimates and unidentified and/or insufficiently managed risk. Use of probabilistic cost estimates like the Washington State Department of Transportation?s CEVP® process (developed by the author and others) has produced more realistic cost estimates, explicitly identified and quantified risk (as input to risk management plans) and early awareness of key project issues. This paper updates previous work (NAT 2004), adds implementation detail for probalistic cost estimating as used by WSDOT, FHWA and other agencies and will address key issues in risk management, as related to probalistic cost estimates.

Jan 1, 2008

By P. Gonzalez, C. Ariyo, L. Holappa

Oxidation state of titanium was determined in CaO-SiO2-TiOxslags in the composition range25–53 per cent CaO, 27–46 per cent SiO2, 10–55 per cent TiOxat 1873K using gas equilibration method. In the experiments, slags with different titanium oxide contents were equilibrated with a known carbon monoxide and carbon dioxide ratio. The results were used to determine the Ti3+and Ti4+contents as well as the activity coefficient ratio of corresponding oxides in the slag. The dependency of the activity coefficient ratio as a function of oxygen partial pressure was determined. Keywords: titanium, titanium oxide, activity, activity coefficient, slag iron, carbon monoxide,carbon doixide, gas, equilibrium.

Jan 1, 2004

By J. C. Carrasco, M. Sánchez, R. Jara, F. Marquez, F. Parada, R. Parra, J. Palacios

In past years, Chile has been the largest copper producer in the world and for 2002 mining represented country average of 10 % of the GDP, accounting for 47 % of the total exportation. As copper sulphides are the main mining resources in the country, the metal is produced using the classical processes of flotation and pyrometallurgical extraction. Seven copper smelter plants, which extends from the northern Atacama desert to the central part of the country produced1,522,000 metric tons of fine copper in 2002, approximately one half of total copper concentrate production, with a notorious environmental impact due to the great amount of slag produced during these extraction steps. In this work, a global characterization of copper pyrometallurgical slags produced and disposed of in Chile and worldwide is done, and the concept of total project development is considered to explain the scopes of the study, recovering different compounds and generating new activities around mining. The presentation is completed with the proposal of various methods and techniques being developed today in a joint project between smelter plants and the University of Concepción, with the support of the Chilean government and mining companies, addressed to generate new materials from copper slag. Recovery of copper, molybdenum, precious metals, silica and iron, that is the most abundant component of the slag, are the goals for this research. Metals, commercial compounds, alloys and different forms of iron oxides for steel industry are proposed products.

Jan 1, 2004

By G. Tranell, L. Kolbeinsen, S. Gaal, J. Safarian

The effect of carbon material properties on the rate of MnO reduction from ferromanganese slag by solid graphite was investigated. A sessile drop technique was used to study the reduction rate of a synthetic slag containing 45 wt% MnO at 1500 and 1600 ºC. Different types of graphite substrates were used and the con-tact angle between slag droplets and substrate were measured in-situ. Moreover, the slag droplet volume during the interaction with the graphite substrates was calculated and normalised. The mathematical relationship between the slag density during the reduction and the normalised slag droplet volumes during the reduction were derived and the MnO reduction curves were then calculated. A method for measuring the slag reactivity of solid carbon was defined and used to qualify the propensity of the different graphites to react with the liquid slag. Some supplementary studies such as manganese evaporation measurement and EPMA analysis for determining the extent of MnO reduction were also carried out. It was observed that there is nota significant difference in the wetting angle of the graphite substrates by the slag, and the wetting is not changed within the temperature range of 1500-1600ºC. However, the changes in the contact angle during the slag reduction at 1600ºC are more than at 1500ºC. The kinetics of MnO reduction is dependent on the type of graphite and it is more dependent on the graphite properties at lower temperatures. On the other hand, the dominant properties of graphite on the reduction rate vary with temperature. A multivariate analysis on the graphite properties and the parameters related to the slag reactivity indicated that the kinetics of MnO reduction is mainly dependent on the temperature, and then on the graphite properties. It was also found that at1500 ºC the surface area and the CO2 reactivity are the most important graphite properties for the slag reduction, suggesting that the reactivity of carbon is rate controlling at 1500 ºC. However, the porosity related parameters are the most important graphite properties at 1600 ºC, suggesting that CO gas desorption is rate controlling at high temperatures.

Jan 1, 2007

By Marie-Pierre Bourdouxhe-Barnich

Since 1997, in partnership with the Laboratoire Central des Ponts et Chaussées in Strasbourg, ProfilARBED has been carrying out a vast study to qualify the improvements jetting can make to vibratory driving of steel sheet piles, and to understand its effect on the surrounding ground and on the sheet piles themselves. The process basically involves discharging a fluid (mostly water, sometimes in association with air) at controlled pressure and/or flow rate near the toe of the sheet pile being driven. The steel jetting pipes are attached to the sheet pile and are connected to the pumps by hoses. The jet of fluid loosens the soil, thus reducing the resistance at the toe of the sheet pile. Depending on ground conditions, the fluid that flows along the pile can reduce skin friction. Four soil types were involved in our experiments. Each site was instrumented: the driving parameters and the geotechnical characteristics of the soil before and after vibratory driving and jetting-assisted driving were recorded. Each test provided its own particular information which contributes to overall thinking on the matter and is of help to project managers who are often confronted with rapid driving to the final depth.

Jan 1, 2002

CAPTAIN JOHN H. BALLAMY John H. Ballamy, Captain on the Regimental Staff of the 103d Engineers, was killed near Fismes, on August 9, 1918. Captain Ballamy was born at Plymouth, Pa., in 1886 and graduated from the High School of that town in 1903. In the following year he began work as a coal miner, and at the same time began the study of mining engineering in the evening and any other spare time. He continued this diligent and energetic practice for many years. For sixteen years he continued in the employment of the Delaware, Lackawanna & Western Railroad Company's coal mining department, first as a practical miner, next as rodman on the survey corps, of which he soon became chief, then draftsman and mining engineer in the company's office. In January, 1916, he was promoted to the position of district engineer in charge of mining engineering work. He became a member of this Institute in September, 1917. CAPTAIN JOHN H BALLAMY. Captain Ballamy's military experience began at the same time as his engineering practice. He was a charter member of Company A, Engineers, N. G. P., which was organized ten years ago. He saw service on the Mexican border as First Lieutenant of this Company, and remained in that position until November, 1916. In July, 1917, he was again called into service and was sent to Camp Hancock, Ga., with the 103d Regiment of Engineers. Before joining this regiment he attended a school for officers at Fort Sill, Okla., where he received special training in field fortifications. In December, 1917, he was commissioned Topographical Captain on the Regimental Staff, and in April, 1918, preceded his regiment by about six weeks to France, where he again attended an officers' training school. He rejoined his regiment on July 15, near Chateau Thierry and was killed near Fismes on August 9, 1918.

Jan 11, 1918

Outsourcing of specialist and non-continuous services is common practice in international mining operations. There is an increasing trend towards this practice in South Africa as a result of the major organisational changes that have taken place in the industry, and as lower revenues and production cost pressures have reduced profit margins. Many specialist functions have been outsourced in the industry for a long time, an example being shaft sinking, which is undertaken by specialist shaft sinking contractors. In the professional services area, some activities have been outsourced, for example the design and construction supervision of tailings dams, but mining related activities such as geology, mine planning and scheduling, engineering, ventilation, and rock engineering, have traditionally been carried out by in-house staff. In this paper some of the industry problems which have led to an increase in outsourcing of professional services are considered. Then the pros and cons of outsourcing are dealt with before outlining the factors which should be taken into account in choosing an outsourcing partner.

Jan 1, 1999

By Eric S. Weiss, Deno M. Pappas, Timothy M. Barton

During the past few years, the Pittsburgh Research Laboratory of the National Institute for Occupational Safety and Health (NIOSH) has been evaluating developments in sealant support systems from a ground control perspective. The proper selection and use of a sealant material can significantly enhance ground control which may result in a decrease in worker related injuries due to ground falls. The purpose of this paper is threefold: to briefly review the current state-of-the-art technology in shotcrete and membrane developments, to evaluate the preliminary findings of a long-term underground study of various types of sealant materials, and to examine installation practices that are critical for an effective sealant material. The underground study utilizes NIOSH’s Lake Lynn Laboratory Experimental Mine to evaluate the long-term performance of several types of shotcrete and membrane materials. Sealant performance to date have been evaluated on a regular basis over a two year period. Although the study is still ongoing, critical mining practices were identified that may seriously effect the bond of the sealant materials to the mine roof and rib; most notably, the importance of scaling and thorough cleaning of the rib prior to application. Also, results froman extensive series of Schmidt Hammer tests found that the shotcrete increased in strength by 70% during the humid summer months.

A methodology has been developed and demonstrated to be effective in reclaiming surface-mined land for a forestry post-mining land use. The Forestry Reclamation Approach (FRA) has been applied, almost exclusively, to flat or gently rolling surfaces. One of the primary steps in the FRA is to loosely grade the top 1.22-m (4-ft) of soil or substitute root growth medium to avoid excessive compaction. Concern has been expressed by regulators and the public that loose grading on steep slopes could lead to slope failures, which is one of the issues that SMCRA sought to correct. A field investigation was conducted at a steep-slope contour operation in eastern Kentucky to test the applicability of FRA in this setting. Final grading was performed according to FRA standards. The surface consisted of two distinct substitute rooting media. One was unweathered gray sandstone and the other was a combination of gray sandstone, brown sandstone, and topsoil. A variety of native hardwoods was planted following the FRA guidelines. The slope was instrumented with 70 survey monuments to monitor for mass movement. The reclaimed spoil was also characterized using bulk density and penetrometer resistance methods. The characteristics of both spoils are similar to those observed on flat to rolling surfaces where the FRA has been used and, after one year, approximately 70% of the trees had survived. There has been no major mass movement of the slope and slope stability analyses indicate that the application of the FRA has little impact on the overall stability of the slope.

Jan 1, 2011

By W. F. Rochow, W. C. Burke

Numerous designs of linings and accessories, including dams, lifters, and heat exchangers, contribute greatly to kiln efficiencies. Greater conductivity is achieved with basic brick than with fireclay and high-alumina refractories, depending largely upon the use of steel plates in radial joints between adjacent brick to increase heat transfer through the lining. Refractory lifters expose all portions of the load to radiant or convective heat and raise some portions to higher temperatures by cascading the load down through the path of the hot gases.

Jan 3, 1955

By G. Broadbent

It is an honour to be invited as a speaker to this ICCR conference and a pleasure to be with you here in South Africa. I have been asked to talk about the competitiveness of coal versus other energy alternatives. Coal supplies nearly one-quarter of the global primary energy. Its most direct competitors are gas, nuclear and renewables. Oil is predominantly for transport fuels. Fuel oil is competitive with coal when crude is below its long-run average price and has some niche opportunities. But I will confine my comments to nuclear, renewables and particularly natural gas as the most potent current competitive threat to coal. Competitiveness is more than just cost and price; there is environmental acceptability, security or reliability and increasingly image. These factors are more of a spectrum than discrete issues. Dollars and cents remain the key issue for competitiveness but one must recognize the impact of politics in sustainable development and energy security.

Jan 1, 2001

The construction of the pipeline was completed in June 1956 and the line placed into operation in December 1956, ie. it has now been in continuous operation for approximately three years under an operating pressure of up to 350 lb. p.s.i.In reviewing the operating experiences of the line we must consider three major factors, which are:(a) The effectiveness to date of the protective methods for prevention of corrosion of the pipeline, ie. the preservation of the asset.(b) The maintenance of the line in regard to interference as to its stability which could be occasioned by erosion of the line, land-slides, accidental interference by the public, or construction authorities, etc.(c) The operating techniques employed.PROTECTIVE METHODS OF THE PIPELINESo to permit a clearer appreciation of the effectiveness of the protection of the! steel pipe against corrosion, I will briefly describe the methods used in the construction of the line.The line, which is 18 in. O.D. by %6 in. thickness steel pipe, is located approximately It miles south of the main Melbourne/Gippsland electrified railway.The steel from which the pipe was manufactured conforms to ASA.A33-1937 with the following modifications.Minimum elongation on a 2 in. test specimen...

Jan 1, 1960

By Sigmund D. Schwarz

INTRODUCTION In late 1970, an experimental geophysical program was undertaken at the Lake Huron Tunnel for the purpose of developing a geophysical technique that could be applied to determining the thickness of rock above the crown of the tunnel and identifying anomalous geologic conditions ahead of the face as the tunnel was advanced. The Lake Huron Tunnel is an 18.5 foot diameter machine bored tunnel having a total length of approximately 6 miles. The easternmost 4.5 mile section of the tunnel extends offshore beneath Lake Huron. At the time this study was started, approximately 1.5 miles of bore remained to be completed at the east end of the project. The tunnel is part of a raw water intake for the City of Detroit water supply. The Lake Huron Tunnel is bored in Antrim shale, a dense marine shale of Mississippian or Devonian age. The west end of the project encountered banded brown shale containing numerous calcareous concretions ranging in size from a few inches to more than 16 feet in diameter. As the tunnel was advanced in an easterly direction, a transition was encountered into very uniform gray shale. One set of prominent vertical joints was encountered with a strike running approximately 15 to 20 degrees askew of the tunnel axis. Bedding is essentially flat. Variable quantities of salt water and natural gas occur in the rock. The results of exploratory drilling carried out for preliminary design studies indicated that as little as 30 to 35 feet of rock cover could be expected under the lake at the east end of the project.

Jan 1, 1997

By J Merrells

Fluor, together with our clients, has yielded significant reductions in the total cost of mining projects by employing a systematic and methodical process of cost reduction. This paper outlines this structured approach to reducing the total cost of projects through the gathering of information, the evaluation of the zero base design, and the development of the execution strategy for the project in the study phase.Over the recent iron ore boom the cost of growth projects escalated rapidly due to a variety of factors including the engineering cost of re-designing facilities, construction in remote areas and an increase in the ‘perceived’ capital requirements for maintainable and operable facilities.Fluor has made strategic steps towards safely reducing the capital intensity of projects, by working with clients to develop zero base designs which utilise the minimum technical requirements in order to meet the function of the plant and then add cost for safety, maintenance and operability only where clearly justified.This paper has set forth a structured three phased approach to focus the team on reducing capital cost while maintaining a low increase in engineering effort.The initial ‘gather’ phase focuses the team on acquiring information and identifying decisions that will need to be made so that the team can prioritise and focus the attention on areas that will provide the greatest benefit. Within this phase the identification of zero base design requirements, review of lessons learnt and analysis of capital cost levers, allows the team to identify the key decisions on the project that will affect the capital cost.In the subsequent ‘evaluation’ phase the team established the zero base design, using the hierarchy of cost reduction as a guide to focusing the team’s attention on high yielding cost saving opportunities.In the final phase the team develops the execution strategy which will yield the least cost using strategies and tools such as modularisation, standardisation, replication, strategic sourcing and 3D design.CITATION:Merrells, J, 2017. Reducing total project cost in the study phase using zero base design, in Proceedings Iron Ore 2017, pp 621–626 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 24, 2017