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By Maurice Bottiau

"Abstract When addressing the performance of deep foundations, many parameters play a role, from adequate soil investigation to performance monitoring and testing. The correct understanding of pile construction, though, remains crucial. After a long period of empirical design and regulations, the last decades have been the ones of theoretical considerations and extensive codes writing. The interaction between technology and design, however, still plays a determinant role. The introduction of hydraulics and the exponential increase in available power on one hand, the miniaturization and the introduction of electronics in control and monitoring systems on the other hand have exerted a major influence on new foundation systems or the evolution and control of existing systems. It appears important to try to take execution related parameters and their control during execution more deeply into account when assessing the final result of the deep foundations and the achieved level of safety and reliability. In this contribution, we will try to analyze how systems, equipment and pile production monitoring and testing can influence the pile performance, and if/how this influence could/should be translated in adapted safety or installation factors. This analysis will run through different categories of piles: driven, augercast and displacement auger piles and bored piles. INTRODUCTIONThe global performance of a deep foundation depends on different aspects (Poulos, 2003):1. Ground investigation2. Design and analysis3. Construction4. Testing5. Performance monitoring6. Remediation and performance enhancementThis paper intends to address the importance of pile construction and the control of it on the final performance of the pile-group of piles. There has been an increasing interest for theoretical analysis over the last 20 years, followed by an increasing impact of regulation and codes. Without denying the importance of the latter, the author wants to point out how installation procedure and project specific parameters can largely influence the reliability of the deep foundation. In this context, detailed and prescriptive standards can miss their objective of intended improvement of accuracy and reliability, but even worse they can adversely impact engineering judgment. In today’s construction world, it is possible to gather installation information which can be of outmost importance for the final deep foundations performance. Therefore, the increase or decrease of installation reliability through adequate pile testing and performance monitoring should be emphasized and should be taken into account in the codes. This is the case already in most advanced codes, but in a limited and insufficiently refined way. After reviewing how codes deal with this issue today, we will show some recent examples of unexpected results due to pile installation. We will try to put these examples into a broader perspective by highlighting some reference and/or recent literature considerations. Finally we will try to summarize how pile testing and installation documentation can increase reliability and attempt to open the debate on how codes could/should allow for more engineering judgment."

Jan 1, 2014

By Scott C. Vollmer

This paper seeks to examine some of the technical factors influencing the deflection of Mechanically Stabilized Earth (MSE) retaining walls based on the authors' field observation of numerous structures. Excessive deflections can be unsightly and can be perceived as wall failure. Deflections can cause cracking or gapping of the facing units and general misalignment. Deflection of the reinforced backfill zone behind the wall face can result in settlement of the backfill zone and adjacent pavement cracking. Deflections can be the result of excessive movement external or internal to the reinforced soil structure. This paper only examines internal factors affecting wall deflections. External factors such as foundation settlement are not discussed.

Jan 1, 2003

By Patrice Favreau

In 1990 the Noranda Technology Centre commenced a project to develop an interactive three-dimensional blast design system using a commerical computer-aided drafting and design package (CADD). The objective was to alleviate the blast engineer from the tedious and time consuming blast layout and design functions normally done by hand. This would allow more time for optimizing blast designs through assessing multiple options. Since several blast design software "tools" already existed at Noranda, the need arose to integrate all the applications into one overall system that shared one common database. The result is BLASTCAD.

Jan 1, 1992

By Carl-John Grävare

This paper deals with some of the systems and equipment that are being developed and/or are in use in Scandinavia. The main subject is the development of loading tests on the piles using monitoring equipment. This paper also describes ground improvement using lime-cement columns, expander body piles and steel core piles.

Jan 1, 2000

Ilmenite production in Western Australia commenced in 1956. There are now five producers, all in the Bunbury-Capel district, and current total production capacity is about 450,000 t.p.a.The deposits occur near the surface and average between 10 and 50 per cent heavy mineral. About 70-85 per cent of the heavy mineral is ilmenite. Other heavy minerals present include leucoxene, zircon, rutile, monazite, and garnet. The ilmenite contains 52-60 per cent Ti02. and is very low in chromium (0·03-0·04 per cent CrS03)Mining is done by sluicing, drag line excavation, or dredging. Primary concentration of the heavy minerals is achieved by spirals, revolving cones, or Reichert cones. After drying and screening, ilmenite is separated from the heavy mineral concentrate by various types of magnetic separator.Separate leucoxene, zircon, rutile, and monazite concentrates are also produced. Each plant uses a different technique and the processes used include chemical attritioning, screen plate electrostatic separation, high tension rolls, air tables, and dry launders.INTRODUCTIONThe treatment of beach sands in the Bunbury/Capel area for the extraction of ilmenite is a very recent development in the mining industry in Western Australia. Nevertheless, since the commencement of production in 1956, ilmenite has become the sixth most important mineral produced (Table 1).The increasing world recognition of Western Australia as a major producer of ilmenite (Table 2) is due primarily to the low chromic bxide content of the mineral (0' 03-0' 04 per cent Cr203), combined with a medium to high titanium dioxide content (54-60 per cent Ti02), supported by large reserves, a stable government, and close access to good shipping facilities. Ilmenite is. produced from these deposits at low cost which enables the industry to compete on world markets despite high rates for sea freights because of the distance from major markets.

Jan 1, 1965

By D. Schleiss

Reduced access to knowledgeable workers is creating challenges for operations. We are doing more 4D Operations - dirty, dull, dangerous, and distant. Personnel costs in these environments are high, and it is not always possible to get the people where you need them. Integrated Operations is a strategy to integrate people, process, and technology for faster and better decision making. Adopting an integrated operations approach can help to relocate personnel, improve collaboration, and align objectives to deliver reduced costs and improved performance. In this paper, the authors will highlight the required infrastructure to enable an Integrated Operations platform. Key decision points for enabling this technology for both Greenfield projects and existing mines will be discussed. Furthermore, the benefits and improved return on investment that result from deployment of an Integrated Operations strategy will be presented.

Jan 1, 2014

By Paloma Lazaro, Moe Momayez

Heat-related illnesses (HRI) are relatively common in both hot surface and underground mining operations. When workers are exposed to extreme heat or strenuous work in a hot environment, they become prone to heat stress. Heat strain is the result of the body’s response to external and internal heat stress. It is therefore vital for the conditions leading to heat strain be detected and treated in a timely manner. Heat-related illnesses are manifested by exhaustion and heat stroke. The predicted heat strain (PHS) [ISO 7933 (2004)] model has been developed to predict the health condition of the worker in terms of core body temperature and water loss. The PHS model tested in this study is based on eight physical parameters that are measured at different intervals during a work shift. They include air temperature, humidity, radiation, air velocity, metabolic rate, clothing insulation, posture, and acclimatization. The model predictions are then compared with a direct physiological measurement, such as core body temperature. We present the results of an extensive study that monitored and predicted body’s response to heat stress under different environmental and working conditions. The PHS model provided reliable results in most instances in comparison with other prediction methods currently in use in the field.

By Paloma Lazaro, Moe Momayez

Heat-related illnesses (HRI) are relatively common in both hot surface and underground mining operations. When workers are exposed to extreme heat or strenuous work in a hot environment, they become prone to heat stress. Heat strain is the result of the body’s response to external and internal heat stress. It is therefore vital for the conditions leading to heat strain be detected and treated in a timely manner. Heat-related illnesses are manifested by exhaustion and heat stroke. The predicted heat strain (PHS) [ISO 7933 (2004)] model has been developed to predict the health condition of the worker in terms of core body temperature and water loss. The PHS model tested in this study is based on eight physical parameters that are measured at different intervals during a work shift. They include air temperature, humidity, radiation, air velocity, metabolic rate, clothing insulation, posture, and acclimatization. The model predictions are then compared with a direct physiological measurement, such as core body temperature. We present the results of an extensive study that monitored and predicted body’s response to heat stress under different environmental and working conditions. The PHS model provided reliable results in most instances in comparison with other prediction methods currently in use in the field.

Ore samples generally require preparation before analysis. Serious problems can occur with contamination degradation and particle size effects. Both grinding element contammation and sample cross contamination havebeen bound to be related to sample hardness and operator technique. For best results with minerals relevant to the steel industry, the use of Siebtechnik-type mills required a combination of careful planning, short grinding periods and intermediate sieving of the sample. The results may be extended to most mineral, rock, and refractory sample preparabons.

Jan 1, 1978

By Sugie Prawono

Jacked pile is the only piling system in which the load capacity of the pile, at any penetration depth, could be monitored directly during its installation process. Each installed pile could have a graph of jacking load versus depth of penetration. For safety purposes, the maximum applied jacking load during installation of a pile could be assumed as the minimum load capacity of the pile. This load capacity will increase with time since the drop in soil strength due to the installation process will recover later on. In order to determine accurately this jacking load, a research was carried out by comparing the load capacity of a pile at certain depths to the jacking load recorded during the installation process. The load capacity could be calculated using cone resistance, qc, and local friction, fs, from Dutch Cone Penetration Test. A graph could be drawn of the load capacity against the depth. By applying a correction factor, a, to the data of local friction, the calculated graph could be matched to the graph of recorded jacking load. The a factor is found to depend on the soil type, which is in this case, represented by the magnitude of cone resistance. The soil type is divided into 3 categories according to qc values (qc < 500 Kpa; 500 Kpa < qc < 2000 Kpa and qc > 2000 Kpa). Graphs of the a factor versus depth and a sample of calculation are presented in this paper for easy application.

Jan 1, 1999

By R. Switalski, M. Schafer, R. Pintabona, M. Kritzer, B. Lukajic, S. Janosko

Methane gas caused an eight-month shutdown of mining operations at the Mill Creek, Phase 3, Tunnel. The gas-related shutdown occurred as the tunnel was advanced to an approximate distance of 2,700 feet, which constitutes approximately18% of the total tunnel length. The construction of an emergency ventilation shaft, a comprehensive program of de-gassing wells and an expanded gas monitoring system were used to mitigate the gas condition. When complete, this tunnel will be utilized to convey and store combined storm and sanitary sewage collected from a portion of Cleveland, Ohio and ten suburbs. This paper will provide an overview of gas related remedial measures and explain how these measures were integrated into the project to ensure safe tunneling conditions.

Jan 1, 2007

By W P. Player

The legislative operating environment, or the mineral regime, that a country has to offer is one of the key determinants that a company wanting to invest in an area takes into account in formulating its investment decision. &nbsp; The New Zealand Government recognises this and the importance of getting the regime right in order to provide for continuing investment in mineral exploration and mining in New Zealand . In recent years, the Government has given considerable attention to developing legislation which provides for investment to take place; for those making the investments to have a stable, fair and open investment environment with government intervention only when considered absolutely necessary because other approaches are not working; and for the people of New Zealand to know that investment must meet acceptable health and safety standards and have acceptable impact on the environment. Also of key importance is having a clearly defined mining regime which includes rules on how to obtain a permit and rules in respect of ongoing permit compliance, rights to develop a mineral resource and permit conditions (in particular, the royalty regime). In New Zealand , these matters will all be addressed in what are referred to as &apos;minerals programmes&apos;. &nbsp; The Crown Minerals Act 1991, which is the legislation governing the allocation and management of permits for Crown owned minerals, requires that the Minister of Energy prepare minerals programmes. Minerals programmes establish the policies, procedures and provisions that the Minister shall follow in exercising his or her functions and powers under the Crown Minerals Act. Minerals programmes set out the principal reasons for and against adopting these policies, procedures and provisions and also restrictions on prospecting, exploration and mining for Crown owned minerals. Essentially minerals programmes define the mining regime for the minerals to which they apply, other than the taxation regime, environmental and health, safety provisions, land access matters and general matters concerning the investment climate.

Jan 1, 1995

By Goutam H. Shahani

Today, the mining and mineral sectors are being impacted by highly fluctuating supply ? demand, extreme price volatility and tremendous market uncertainty on a world-wide basis. This pattern is expected to continue for the foreseeable future. In particular, large consumers of tonnage quantities of industrial gases (oxygen, nitrogen) all have to make informed investment decisions in this uncertain economic environment. Plant owners ? operators need to carefully examine their current and future industrial gas needs in order to develop the most cost-effective industrial gas plant configuration. This can be done by partnering with an experienced engineering company that offers a complete technology portfolio for producing industrial gases. Ideally, the mineral and engineering companies have to work together as a single team to identify the most efficient and economic plant design. This includes an in-depth assessment of capital and operating costs, in order to deliver an optimal solution, taking plant reliability and process safety into account. It is important to consider all the industrial gas needs at a given manufacturing complex, in conjunction with available utilities and infrastructure to develop the best possible long term solution. Oxygen (O2) requirements include: oxygen enriched and oxy-fuel combustion, smelting and hydrometallurgical operations. Nitrogen (N2) is used for annealing. All of these industrial gas requirements have to be examined at a given site over a long term horizon in a holistic manner. Cryogenic air separation was first practiced at a commercial scale in 1902. Since then, the technology has been constantly refined to reduce cost; and improve reliability and flexibility. Today, using advanced engineering techniques, including proprietary process simulation, and modern fabrication techniques, it is possible to build air separation plants that are both low cost and high quality at the same time. It is important to work with an engineering company that owns a complete portfolio of industrial gas technologies, functional engineering capabilities and a variety of plant solutions. Such a partnership can quickly identify a ?sweet spot? for a given situation. By drawing on experience gained from hundreds of projects, it is possible to quickly optimize a given requirement. In situations where a customer wants a complete solution it may be appropriate to provide an air separation plant on a turn-key basis. This will enable the mining and mineral processor to focus on their core business. By using global procurement and construction capabilities it is possible reduce cost and improve project execution, thereby making industrial gas plant procurement simpler and cheaper for the mining and mineral sector.

Nov 1, 2011

THE following really forms the second part of, or a sequel to, a paper, &quot; Ventilating Metalliferous Mines: a Method of Attack,&quot; read before the Broken Hill Branch of the Australasian Institute of Mining and Metallurgy in May, 1920. In that paper the writer advocated a consideration of the question of ventilation in metal mines from a different aspect to that &apos;which had hitherto prevailed locally. Various factors regarded as having an important bearing on the subject were set forth, together with the results of observations made during ventilation tests carried out at the mining department of the Zinc Corporation.During the subsequent discussion the question was raised of the possibility of any practical application of the method of attack described, and also whether the theoretical considerations mentioned were likely to be of any real utility to the mining engineer engaged in ventilation work in a metalliferous mine.

Jan 1, 1923

By William H. Langer

Large amounts of limestone fines co-produced during the processing of crushed lime-stone may be useful in the sequestration of carbon dioxide (CO2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point sources such as cement manufacturing. AWL reactants are readily available, inexpensive and environmentally benign. Waste CO2 is hydrated with water to produce carbonic acid. This reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities to within about 10 km (6 miles) of the coastline. The majority of U.S. coastal power-generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufacturers and research scientists. There is a concern that CO2 generated from human activities is contributing to climatic and environmental changes. Approximately one-third of anthropogenic CO2 emissions come from burning fossil fuels to generate electricity. Each power plant is capable of emitting several million tons of CO2 annually. A variety of other industrial processes, such as cement manufacture, oil refining, and iron and steel production, also emit large amounts of CO2. The level of atmospheric CO2 can be reduced by capturing CO2 from point-source emissions and storing or sequestering it in isolation from the atmosphere (U.S. Department of Energy, 2003). In 1999, G.H. Rau and K. Caldeira proposed a geochemistry-based method that is referred to as accelerated weathering of limestone (AWL) in a paper titled ?Accelerating carbonate dissolution to sequester carbon dioxide in the ocean ? geochemical implications.?

Jan 1, 2009

By Klaus Rieker

The main train station of Leipzig in Germany is currently being upgraded from a head station to a partially thru station. In order to achieve this, significant ground improvements are necessary. Soil freezing for example is used to create the excavation box retaining walls. The freezing works will be carried out from two tunnels with an inner diameter of 2.4 m (~ 8ft). The tunnels were constructed by the pipe jacking method. The cutter head of the machine was equipped with discs and scrapers. Driving and excavation was carried out using a bentonite supported face. Due to the small arrival shafts, the machine had to be lifted out in components. The essential limitation of settlements during the drives was achieved even better than expected.

Jan 1, 2008

IN dealing with this subject the intention is not to write a detailed description of the various methods in vogue on the Kalgoorlie field, but rather to give a brief outline of three of the methods which are most universally in force, and from which, ultimately, a few comparisons may be drawn. The three methods which the writer proposes embodying in this article are known as &quot;The Rill,&quot; &quot;The Flatback,&quot; and &quot;The Shrinkage.&quot; For comparative purposes each method will be applied to a block of ore 500 feet in length, and opened up by levels 200 feet apart.&quot;The Rin&quot; System. It is necessary in this system, for facilitating mullocking, to make connections between levels by rising and winzing at about every 100 feet or 150 feet along the orebody. After the leading stope is beaten off for the full length ofthe drive, the level is timbered. Single stulls are put in up to a width of fourteen feet. If the span is too great for stulls, set timbers or saddleback stuUs are used. Stulls are lagged over with 4-in gimlet poles, and wooden chutes are built at intervals of 50-feet. Ore passes are cribbed up through the filling directly above each chute, and are constructed of 7-in. round timber or 9 in x 3 in square timber, the passes measuring 4 ft x 4 ft in the clear.Occasionally a double pass may be carried up, one side serving as a travelling way. Stoping is commenced off the winzes, and rills are gradually formed, one on either end of each winze. The rills are generally at an angle of 37&#176; off the horizontal, this allowing for the boring...

Jan 1, 1909

Vein swarms in metamorphic terranes such as the Otago Schist Belt, New Zealand provide evidence of past hydrothermal flow systems leading to fault initiation and reactivation. A major episode of hydrofracturing and fluid redistribution occurred during early Cretaceous exhumation of the schist belt. As a result, presently exposed lower greenschist facies greyschists in NW Otago are pervaded by abundant quartz-filled hydraulic extension fractures with associated normal faults hosting quartz¦scheelite¦gold mineralisation. Once the effects of Cenozoic folding have been removed, a regional subhorizontal schist foliation contains an aligned array of subvertical hydrofractures striking NNW, striking parallel to a set of low-slip conjugate normal faults; the array extends over an area >1500 km2 and over a depth interval >5 km. The hydrofracture array comprises a mesh of interlinked extensional-shear and pure extension veins. These veins show mutually cross-cutting relations. Extensional hydrofracturing apparently preceded the development of major throughgoing normal faults. Low-displacement normal faults are infilled with laminated quartz (¦ scheelite) veins (

Jan 1, 2002

By Heinz Brandl

Box-shaped pile and diaphragm wall foundations have proved suitable for transferring heavy loads of bridges, power plants, tanks, towers or other buildings in a concentrated form into the ground. The bearing-deformation behaviour and the earthquake resistance of such "box-foundations" are superior to those of conventional pile groups. The reason lies in the reduction of lateral soil displacement and in the composite effect between concrete elements and the enclosed soil. The paper describes results of comprehensive model tests and in situ measurements, theoretical aspects and case histories.

Jan 1, 2002

By Zachary Q. Maassen

The purpose of this paper is to highlight the environmental benefits of properly managing slurry waste as it is generated on site. The following projects will be used to illustrate the importance of proper onsite waste management. Project: Jet Grout Backflow Dewatering The goal was to dewater the backflow directly onsite to produce a dry, solid waste and reusable water. The backflow spoil was pumped directly to the dewatering system as it was generated. Utilizing mechanical separation equipment and flocculation polymer the waste volume was reduced by 44%. Due to the site footprint and high volumes, slurry waste removal and onsite processing were the only two feasible options. Onsite dewatering proved to be the environmentally beneficial option as it eliminated the need for slurry waste hauling and disposal. The benefits of utilizing a dewatering system are listed below: Project: Soil Mixing Spoil Recycling for Slurry Wall Construction In this application the spoils generated contain bentonite mud, cement mixture and organic ground soils. The goal of this project was to process the backflow mixture to recover reusable bentonite mud and separate the soil as a dry, stackable waste product. The treatment system replaced the traditional method of vacuum truck extraction and facility disposal. The environmental benefits of properly handling the backflow is a decrease in fresh water usage, bentonite additive reduction, and the reduction of CO2 emissions. The paper will consist of a project scope, technical equipment and process description, environmental impact reduction calculations and lessons learned for each project.

Jan 1, 2018