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By Bernard Hertlein, Chia K. Tan

"The move to LRFD methods for structural design by AASHTO, ACI, AISC , ASCE, and the FHWA has been a major change for the American construction industry. The deep foundations industry has arguably been placed most at risk by this situation, because of the need for, and the difficulty of providing, reliable quality assurance.LRFD is attractive for both the owner and the engineer because it promises cost reductions, but the assumption underlying LRFD is often overlooked - that the acceptable margin of safety can be rationally reduced, thus saving costs, provided that all the factors involved are closely controlled. This means that both the quality of the materials and the quality of the construction work must be closely monitored, and held to an acceptable standard.This paper describes the type of comprehensive quality management program that is needed in deep foundation construction projects based on LRFD. Case histories are used to illustrate the importance of both adequate inspection and reliable testing to a comprehensive quality management program.IntroductionOver the last thirty years, the major organizations that set standards and practice policies for the American construction industry, such as the American Association of State Highway and Transportation officials (AASHTO), the American Concrete Institute (ACI) , The American Institute for Steel Construction (AISC), the American Society of Civil Engineers (ASCE), and the Federal Highway Administration (FHWA), have embraced Load and Resistance Factor Design (LRFD) as an alternative to, and in some cases, a complete replacement for, Allowable Stress Design (ASD). AASHTO first published a new set of LRFD-based design guidelines for bridges in 1996, with several revisions in 1997, 1998, and 1999 (AASHTO, 1996). The 1996 AASHTO Bridge Design Code was the first in the United States that required foundations to be designed using LRFD procedures. LRFD has a clear advantage over conventional ASD where variability in material strength, bias in design methodology, and degree of construction quality can be rationally accounted for to achieve an acceptable level of risk."

Jan 1, 2005

By Jamal Rostami, Richard Kastner, Ahmad Ramezanzadeh

Improving the accuracy of the performance prediction models for hard rock Tunnel Boring Machines (TBMs) is important in estimation of the schedule and cost of tunnelling in related projects. The effects of rock mass on performance of TBMs has been studied extensively, yet due to the complex nature of the process, impact of many parameters influencing machine advance rate are not very clear and there is still room for improvements. More accurate estimates can be obtained by better understanding of operating parameters in various geological conditions and can lead to matching machine specifications with job conditions, optimizing machine performance, and avoiding long delays and downtime for increased productivity. This paper will offer review of two case histories including Queens Water tunnel in New York and KCRC project in Hong Kong. The analysis of the available field data, including the geological back mapping and results of laboratory testing of rock mechanical properties, machine operational parameters and achieved rate of penetration will be presented. This includes statistical analysis of available field data to provide a better understanding of the influence of rock mass properties on performance of hard rock TBMs as well as related formulas to improve performance estimates.

Jan 1, 2005

By Dale S. Preece, Stephen H. Chung

Electronic detonators and the attendant precise detonation timing that they facilitate are having a measurable effect on rock blasting in terms of improved fragmentation and vibration control. These improvements are increasingly well documented which is driving the expanding use of electronic detonators. In spite of the growing body of positive evidence concerning the benefits of precise delay timing, very little work has been done to document the impact of electronic detonators on the movement of rock. In this study 3-D computer programs, used to predict blasting induced rock heave, including the effects of detonation timing, are used to simulate the effect of precise timing on rock movement. Implementation includes quick, precise timing between blastholes going down a row and then much longer delays between rows of blastholes. For example an effective blast design might call for precise 3 ms delays between blastholes along a row and then 60 or 72 ms between rows. Several options are studied in this paper using computer simulations to draw some conclusions about the underlying physics affecting the process and how precise timing might have a positive impact on blasting induced rock motion.

Jan 1, 2005

By Dan Armour

Bolting solutions traditionally offered only wet drilling or dry drilling options; each with advantages and disadvantages. Joy Mining Machinery has developed a Mist Drilling System that incorporates the best of both types of drilling. Compared to wet drilling, mist drilling offers as much as a 90% reduction in water use. As a result, floor and roof conditions are tremendously improved. This offers a safer and more comfortable work environment for operators. Mist drilling can offer a significant reduction in noise levels compared to dry drilling and in recent trials, bit life has been greatly improved. Holes are cleaner and operators experience less exposure to respirable dust.

Jan 1, 2005

By J. -C. Trickett

The high-resolution three-dimensional (3-D) seismic reflection data acquired for Impala Platinum between 1998 and 2002 in the western Bushveld Igneous Complex form an integral part of Impala?s mine planning and development programme. These data are of sufficiently high quality to provide unprecedented 3-D models of the geological structure of the Merensky Reef and UG2 Chromitite Reef, from which the mine deduces the size, geometry and distribution of mineable blocks. Conversely, the seismic data details zones of un-mineable ground caused by structural disturbances in the form of potholes, fault zones and pegmatoid intrusions. Furthermore, variations in dip and strike are well imaged, allowing the mine planners to optimize the mine design and layout. Current interpretation work is focused on enhancing the accuracy of these geological models even further through the analysis of ?seismic trace attributes.? Preliminary testing on the Impala Platinum 3-D seismic volume has shown that attribute analysis has the potential to illuminate a number of geological reef disturbances that are otherwise ?invisible? in the original seismic time volume. Potential areas of improvement include inter alia: ?Improved definition of major fault zones ?Improved definition of zones of reef depression (?slumping?) ?Identification of reef terracing and/or reverse dip. Keywords: 3-D reflection seismics; Impala Platinum Ltd; seismic attribute analysis; seismic micro technology (SMT); rock solid attributes; dip-azimuth; instantaneous phase and similarity.

Jan 1, 2005

By T. ?kre, O. M. Dotterud, S. Haarberg, J. Thonstad, G. M. Haarberg

An electrowinning pilot plant has been constructed at Falconbridge Nikkelverk A/S, Kristiansand, Norway. The equipment consists of a mixing tank where the electrolyte composition and temperature are controlled, an electrowinning tank equipped with five cathodes and six anodes of commercial size and design and a dechlorination facility. Electrowinning experiments were carried out in this pilot plant using acid cobalt chloride solution from the cobalt tankhouse. Key parameters were varied to obtain an improved understanding of the cobalt electrowinning process, focusing on the detrimental deposition of cobalt oxide on dimensionally stable anodes. The extent of anode scaling was found to be dependent on the electrowinning conditions. Low pH, temperature and cobalt concentration resulted in less scale being formed, however at the expense of cobalt current efficiency and cell voltage, adversely affecting electrowinning production capacity and energy consumption. When operating at high acidity, pH in the anolyte was higher than in the catholyte, which is believed to be due to H+ ions taking part in the current transport across the diaphragm, migrating out of the bags surrounding each anode.

Jan 1, 2005

By Andre Balt, Pierre Hofmeyr

It is only recently that automation has been applied to mining analytical laboratories. This paper describes the use of automation in the laboratory analytical process of hard-rock mining and geological samples and slurries in mining concentrator plant process control laboratories. Types of analysis include fire assay, XRF, ICP and wet chemistry. The benefits of automation are reduced unit cost of analyses, greatly reduced staff requirements, higher quality of data and very fast turn-around times.

Jan 1, 2005

By M. Mead, J. Dumouchel, W. Yule, J. Giroux

The QMM mineral sands of South East Madagascar contain approximately 1,900 million tonnes of mineable sand with a total heavy mineral (THM) content of roughly 4.5wt%. The QMM deposits are the world’s largest known reserves of 60% TiO2 ilmenite and also contain a small volume of zircon. The deposits are semi-continuous and homogenous and the mineralized sands are free flowing with minimal overburden, induration & slimes. These characteristics are favourable to dredge mining and allow the application of conventional wet gravity, electrostatic & magnetic separation to final products. A mature THM mineral suite of high valuable heavy minerals (VHM) content has enabled the development of a relatively simple separation process.

Jan 1, 2005

By Rudolph P. Frizzi

Structures supported on ACIP and DD piles perform successfully when quality control is maintained from the initial site subsurface investigation through pile design, bidding, and construction. The four stages of ACIP / DD pile construction are: preparation, augering the pile, grout / concrete placement, and reinforcement installation. During all four stages, careful observations and communication between the contractor and the owner's engineering inspection personnel are vital to successful pile completion. Automated monitoring equipment (AME) exists to supplement, but not replace, the field personnel's observations during the pile augering and grouting operations. Full-scale field load testing is done to verify the pile's geotechnical and structural design, and the contractor's pile installation means and methods, using several procedures including: conventional top loading, high-strain dynamic, rapid axial compression (i.e. Fundex PLT and Statnamic), and Osterberg Cell. Non-destructive sonic testing is performed to investigate the below-grade sectional properties of the completed pile; such methods include: low-strain impulse testing, and single-hole and cross-hole sonic logging. Post-construction observations are necessary to verify pile location and top properties prior to overlying cap construction.

Jan 1, 2005

By A. K. Dikshit, H. R. Murty, S. K. Gupta

This paper deals with the development of environment performance indicators (EPIs) for the steel industry. Environmental performance has become one of the key measures of business success. Emergence of continuing pressure from customers, employees, government and NGOs for environmental performance evaluation (EPE) of industries has led to evolve a framework for the development of sector specific environmental performance indicators. EPIs can be used by steel industry for assessing the continual improvement in environmental perfromance, selecting various eco-friendly options, benchmarking, environmental reporting, technology assessment and dissemination, evaluating environmental impacts and building EPIs based environmental management systems. The objective of this paper is to develop EPIs for steel industry and provide framework for development of environmental performance indicators based environmental management system and its integration with the overall management system. An indepth discussion has been presented concerning identification of EPIs, eavaluation of significance of EPIs, their prioritization and its integration with Environmental Management Systems. A new methodology has been proposed for implementing EPIs based environmental management systems . The material presented is derived in part from PhD studies of Rajesh Kumar Singh.

Jan 1, 2005

By R. L. Virta

Common clay is a natural, fine-grained material composed of hydrous aluminum silicates. Shale is a laminated sedimentary rock that is formed by the consolidation of clay, mud or silt. Production About 160 companies produced common clay and shale in 41 states. In states not reporting production, common clay and shale probably was mined and sold for construction applications by companies not participating in the U.S. Geological Survey’s canvass of producers.

Jan 1, 2005

By Paul Laframboise, Nigel MacDonald, Mike Hallewell, Robert Thorpe

"Galmoy Mine, owned by Arcon Mines Limited, has operated since 1997, and is one of three operating lead/zinc mines in Ireland. Changes in ore type starting in mid 2002 created challenges to metallurgical operations at Galmoy. This resulted in unacceptable lead and zinc flotation performance, which prompted initiation of a formal plant review and a subsequent stabilization programme. This involved a structured review of operational practices, development of a new Standard Operating Procedure (SOP) which in turn led to significant changes in process control equipment needs in conjunction with extension of zinc flotation cell residence time.This paper will describe the metallurgy of the Galmoy operation. Reasons for the poor metallurgy experienced in 2002 will be described, as well as the solutions identified to overcome these problems. By the second quarter of 2003, these solutions had been implemented and recoveries had risen to record levels.INTRODUCTIONGeneralGalmoy Concentrator is located in County Kilkenny (Refer to Figure 1 below) and was constructed during 1996 and commissioned in 1997.The concentrator at Galmoy had been designed initially to treat 650,000 tonnes per annum of primarily CW ore type. The main mineral of economic significance was sphalerite (Typically 10 to 11% Zn) with some minor galena (0.7%Pb) in a dolomite (Magnesium Carbonate) host rock.The only other competing sulphide mineral was pyrite (Circa 3 to 5% Fe in Mill Feed. This CW ore type predominated the first 6 years of production, but in August 2002, the ore mineralogy changed due to significantly higher levels of pyrite rich G ore body being blended in with CW ore."

Jan 1, 2005

By K. Poorhaydari, B. M. Patchett, D. G. Ivey

In this paper, some applications of carbon extraction replicas, as samples for transmission electron microscopy (TEM), are discussed. Modern high strength microalloyed (HSMA) steels, used as structural or pipeline materials, have very small grains with substructures. Replicas used in TEM can resolve the grain boundaries and can be used for grain size measurements in cases where the small size of the grains pushes the resolution of conventional optical microscopes. The grain size variations obtained from replicas correlated very well with mechanical property variations, indicated by hardness, in the fine-grained heat-affected zone and base metal of some welded HSMA steels. Replicas are also very suitable samples for precipitate examination with analytical TEM. Advantages and limitations of the application of replicas, as well as some corrections for the estimation of the volume fraction of fine precipitates, are discussed.

Jan 1, 2005

By K. Adham, C. Lee

The demand for nickel is continuing to exceed inventories, and producers are working vigorously to increase capacity. Many nickel processes utilize the fluidized bed technology for its fast heat and mass transfer, excellent temperature control and low maintenance. The following four nickel applications of the fluidized bed technology have been commercialized: I) Sulfide ore roasting; II) Nickel sulfide (matte) roasting; III) Nickel oxide reduction; IV) Nickel chloride pyrohydrolysis. This paper examines the issues surrounding the application of fluidization technology to the above processes, from the stand point of the engineer modeling the process and designing the key equipment, based on the historical success stories and the fundamental principles of flow sheet synthesis. Using the available data in open literature, typical flow diagrams (with convenient bases of 1 t/h feed or product) are developed to illustrate the relative flow rates and to highlight the key features of each application. In addition, some historical background information is provided for each process with supplemental notes with regards to our company's involvements.

Jan 1, 2005

By J. E. Amadi-Echendu, F. Stober, J. Ndlovu, L. R. Nelson

The Polokwane Smelter Complex (PSC) relies on a single 68MW high-intensity six-in-line furnace to smelt a planned 650 000 t/a dry concentrate to produce a platinum group metals (PGM)-bearing matte. As typical of a greenfields venture, considerable attention was paid to the project development and implementation stages of design, engineering, construction and commissioning. Somewhat unusual though, was the role of a dedicated multi-disciplinary "Operational Readiness" and support team, comprising the owners team and specialists from the furnace designer, HATCH, to effect a safe and rapid ramp-up to the design smelter capacity of 68MW. The challenges encountered in developing an effective partnership will be discussed. The modus operandi and roles of the "Operational Readiness" team during the design, procurement, construction and commissioning stages as well as that of the operational support team within the overall ramp-up objective will be presented. The "Operational Readiness" team was responsible for:

Jan 1, 2005

By ?. V. Kabanov

n considered operation hydraulic and kinematic circuits of deep-water installation for sampling a ground from a sea-bottom are submitted. Control by setters is made remotely from a service station with the help of a system of telemechanics. Migration of apparatus along a bottom is ensured with the help of force of a response of a jet and Archimedean force. The mathematical exposition of the device composed and computer simulation is Design parameters are defined and static performances are obtained. Operation is in a stage of manufacture of working drawings. There are patents of Russia.

Jan 1, 2005

By Charles Dowding, Cathrine Aimone-Martin

This article summarizes an investigation of the structural response of a brick façade home in New Mexico. The subject Ricter residence was located some 1100 to 1400 ft away from an aggregate quarry, and was subjected to a maximum peak particle velocity and air blast over pressure of 0.29 ips and 122 dB, respectively. Superstructure (corner) and mid-wall responses to blasting and human induced activities were measured. An existing exterior crack in the brick work was instrumented to measure crack width response to blasting, human induced activities, and environmentally induced changes in temperature and humidity. Crack and structure response data were correlated with ground velocity and airblast excitations. Amplification of ground motions at the upper structure were calculated and compared with values for typical wood frame structures. The natural frequency and damping characteristics of the structure were determined to compare with measured amplification values. Wall strains produced by bending and inplane tension strains were computed from upper corner structure response and compared to failure strains for drywall and brick veneer. Calculated strains were found to be far lower than those required to crack brick and environmentally induced crack response was found to be far greater than that caused by blast induced ground motion or airblast overpressures

Jan 1, 2005

By Josh Struble, Fu Yuet, Jan Zywiel, Kevin King

This paper discusses the application of Integrated Inertial/GPS technology for position determination of earthmoving equipment in an open-pit mine. Different GPS augmentation methodologies are introduced and discussed. Principles for the operation of the Applanix POS MC (Position and Orientation System for Machine Control) are also presented, together with test results conducted at the Twin Creeks Newmont mine, using the POS MC and Caterpillar’s CAES (Computer Aided Earthmoving System).

Jan 1, 2005

By I Jabou, D G. Blazak, L C. S Hogarth

The R70 test is a good indicator of coal reactivity to oxygen and is commonly used to provide a rating of propensity for self-heating. Tests performed by The University of Queensland Spontaneous Combustion Testing Laboratory have resulted in the development of a large database that shows the impact of coal quality on this parameter. From these results it is possible to infer an R70 value, which can be used to gain an appreciation of the intrinsic coal reactivity before it is even tested. However, any interpretation of R70 values must consider the influences of coal rank, mineral matter and moisture content to provide a better understanding of the spontaneous combustion risk of a particular coal.

Jan 1, 2005

By D. Goodings, W. L. Fourney, Bonenberger, R., Uli Leiste

The Dynamics Effects Laboratory at the University of Maryland conducted a series of very small scale tests to measure the impulse delivered to a plate by the detonation of an explosive charge which was buried in saturated sand. These tests were conducted to support a full scale tests series being supported by the Navy (NSWC Indian Head Division) to learn more about loads applied to structures by explosive detonation. For each of the tests being predicted, a series of three tests were conducted at Maryland, one with a 0.203 gm charge, one with a .609 gm charge, and one with a 3.3 gm charge. A high speed digital camera (500 frames per second) was used to record the displacement of the plate as a function of time. From this the initial velocity of the plate was determined and then the impulse delivered to the plate by the explosive. A best fit line through the data was determined for the three model tests conducted and this equation was used to extrapolate the predicted impulse for the full scale tests.

Jan 1, 2005